postgresql/src/include/nodes/parsenodes.h

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/*-------------------------------------------------------------------------
*
* parsenodes.h
* definitions for parse tree nodes
*
* Many of the node types used in parsetrees include a "location" field.
* This is a byte (not character) offset in the original source text, to be
* used for positioning an error cursor when there is an error related to
* the node. Access to the original source text is needed to make use of
* the location.
*
*
* Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
2010-09-20 22:08:53 +02:00
* src/include/nodes/parsenodes.h
*
*-------------------------------------------------------------------------
*/
#ifndef PARSENODES_H
#define PARSENODES_H
#include "nodes/bitmapset.h"
#include "nodes/primnodes.h"
#include "nodes/value.h"
#include "utils/lockwaitpolicy.h"
/* Possible sources of a Query */
typedef enum QuerySource
{
QSRC_ORIGINAL, /* original parsetree (explicit query) */
QSRC_PARSER, /* added by parse analysis (now unused) */
QSRC_INSTEAD_RULE, /* added by unconditional INSTEAD rule */
QSRC_QUAL_INSTEAD_RULE, /* added by conditional INSTEAD rule */
QSRC_NON_INSTEAD_RULE /* added by non-INSTEAD rule */
} QuerySource;
/* Sort ordering options for ORDER BY and CREATE INDEX */
typedef enum SortByDir
{
SORTBY_DEFAULT,
SORTBY_ASC,
SORTBY_DESC,
SORTBY_USING /* not allowed in CREATE INDEX ... */
} SortByDir;
typedef enum SortByNulls
{
SORTBY_NULLS_DEFAULT,
SORTBY_NULLS_FIRST,
SORTBY_NULLS_LAST
} SortByNulls;
/*
* Grantable rights are encoded so that we can OR them together in a bitmask.
* The present representation of AclItem limits us to 16 distinct rights,
* even though AclMode is defined as uint32. See utils/acl.h.
*
* Caution: changing these codes breaks stored ACLs, hence forces initdb.
*/
typedef uint32 AclMode; /* a bitmask of privilege bits */
#define ACL_INSERT (1<<0) /* for relations */
#define ACL_SELECT (1<<1)
#define ACL_UPDATE (1<<2)
#define ACL_DELETE (1<<3)
#define ACL_TRUNCATE (1<<4)
#define ACL_REFERENCES (1<<5)
#define ACL_TRIGGER (1<<6)
#define ACL_EXECUTE (1<<7) /* for functions */
#define ACL_USAGE (1<<8) /* for languages, namespaces, FDWs, and
* servers */
#define ACL_CREATE (1<<9) /* for namespaces and databases */
#define ACL_CREATE_TEMP (1<<10) /* for databases */
#define ACL_CONNECT (1<<11) /* for databases */
#define N_ACL_RIGHTS 12 /* 1 plus the last 1<<x */
#define ACL_NO_RIGHTS 0
/* Currently, SELECT ... FOR [KEY] UPDATE/SHARE requires UPDATE privileges */
#define ACL_SELECT_FOR_UPDATE ACL_UPDATE
/*****************************************************************************
* Query Tree
*****************************************************************************/
/*
* Query -
* Parse analysis turns all statements into a Query tree
* for further processing by the rewriter and planner.
*
* Utility statements (i.e. non-optimizable statements) have the
* utilityStmt field set, and the Query itself is mostly dummy.
* DECLARE CURSOR is a special case: it is represented like a SELECT,
* but the original DeclareCursorStmt is stored in utilityStmt.
*
* Planning converts a Query tree into a Plan tree headed by a PlannedStmt
* node --- the Query structure is not used by the executor.
*/
typedef struct Query
{
NodeTag type;
CmdType commandType; /* select|insert|update|delete|utility */
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QuerySource querySource; /* where did I come from? */
uint32 queryId; /* query identifier (can be set by plugins) */
bool canSetTag; /* do I set the command result tag? */
Node *utilityStmt; /* non-null if this is DECLARE CURSOR or a
* non-optimizable statement */
int resultRelation; /* rtable index of target relation for
* INSERT/UPDATE/DELETE; 0 for SELECT */
bool hasAggs; /* has aggregates in tlist or havingQual */
bool hasWindowFuncs; /* has window functions in tlist */
bool hasSubLinks; /* has subquery SubLink */
bool hasDistinctOn; /* distinctClause is from DISTINCT ON */
bool hasRecursive; /* WITH RECURSIVE was specified */
bool hasModifyingCTE; /* has INSERT/UPDATE/DELETE in WITH */
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
bool hasForUpdate; /* FOR [KEY] UPDATE/SHARE was specified */
bool hasRowSecurity; /* row security applied? */
List *cteList; /* WITH list (of CommonTableExpr's) */
List *rtable; /* list of range table entries */
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FromExpr *jointree; /* table join tree (FROM and WHERE clauses) */
List *targetList; /* target list (of TargetEntry) */
List *withCheckOptions; /* a list of WithCheckOption's */
List *returningList; /* return-values list (of TargetEntry) */
List *groupClause; /* a list of SortGroupClause's */
Node *havingQual; /* qualifications applied to groups */
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
List *windowClause; /* a list of WindowClause's */
List *distinctClause; /* a list of SortGroupClause's */
List *sortClause; /* a list of SortGroupClause's */
Node *limitOffset; /* # of result tuples to skip (int8 expr) */
Node *limitCount; /* # of result tuples to return (int8 expr) */
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List *rowMarks; /* a list of RowMarkClause's */
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Node *setOperations; /* set-operation tree if this is top level of
* a UNION/INTERSECT/EXCEPT query */
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List *constraintDeps; /* a list of pg_constraint OIDs that the query
* depends on to be semantically valid */
} Query;
/****************************************************************************
* Supporting data structures for Parse Trees
*
* Most of these node types appear in raw parsetrees output by the grammar,
* and get transformed to something else by the analyzer. A few of them
* are used as-is in transformed querytrees.
****************************************************************************/
/*
* TypeName - specifies a type in definitions
*
* For TypeName structures generated internally, it is often easier to
* specify the type by OID than by name. If "names" is NIL then the
* actual type OID is given by typeOid, otherwise typeOid is unused.
* Similarly, if "typmods" is NIL then the actual typmod is expected to
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
* be prespecified in typemod, otherwise typemod is unused.
*
* If pct_type is TRUE, then names is actually a field name and we look up
* the type of that field. Otherwise (the normal case), names is a type
* name possibly qualified with schema and database name.
*/
typedef struct TypeName
{
NodeTag type;
List *names; /* qualified name (list of Value strings) */
Oid typeOid; /* type identified by OID */
bool setof; /* is a set? */
bool pct_type; /* %TYPE specified? */
List *typmods; /* type modifier expression(s) */
int32 typemod; /* prespecified type modifier */
List *arrayBounds; /* array bounds */
int location; /* token location, or -1 if unknown */
} TypeName;
/*
* ColumnRef - specifies a reference to a column, or possibly a whole tuple
*
* The "fields" list must be nonempty. It can contain string Value nodes
* (representing names) and A_Star nodes (representing occurrence of a '*').
* Currently, A_Star must appear only as the last list element --- the grammar
* is responsible for enforcing this!
*
* Note: any array subscripting or selection of fields from composite columns
* is represented by an A_Indirection node above the ColumnRef. However,
* for simplicity in the normal case, initial field selection from a table
* name is represented within ColumnRef and not by adding A_Indirection.
*/
typedef struct ColumnRef
{
NodeTag type;
List *fields; /* field names (Value strings) or A_Star */
int location; /* token location, or -1 if unknown */
} ColumnRef;
/*
* ParamRef - specifies a $n parameter reference
*/
typedef struct ParamRef
{
NodeTag type;
int number; /* the number of the parameter */
int location; /* token location, or -1 if unknown */
} ParamRef;
/*
* A_Expr - infix, prefix, and postfix expressions
*/
typedef enum A_Expr_Kind
{
AEXPR_OP, /* normal operator */
AEXPR_OP_ANY, /* scalar op ANY (array) */
AEXPR_OP_ALL, /* scalar op ALL (array) */
AEXPR_DISTINCT, /* IS DISTINCT FROM - name must be "=" */
AEXPR_NULLIF, /* NULLIF - name must be "=" */
AEXPR_OF, /* IS [NOT] OF - name must be "=" or "<>" */
AEXPR_IN, /* [NOT] IN - name must be "=" or "<>" */
AEXPR_BETWEEN, /* name must be "BETWEEN" */
AEXPR_NOT_BETWEEN, /* name must be "NOT BETWEEN" */
AEXPR_BETWEEN_SYM, /* name must be "BETWEEN SYMMETRIC" */
AEXPR_NOT_BETWEEN_SYM /* name must be "NOT BETWEEN SYMMETRIC" */
} A_Expr_Kind;
typedef struct A_Expr
{
NodeTag type;
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A_Expr_Kind kind; /* see above */
List *name; /* possibly-qualified name of operator */
Node *lexpr; /* left argument, or NULL if none */
Node *rexpr; /* right argument, or NULL if none */
int location; /* token location, or -1 if unknown */
} A_Expr;
/*
* A_Const - a literal constant
*/
typedef struct A_Const
{
NodeTag type;
Value val; /* value (includes type info, see value.h) */
int location; /* token location, or -1 if unknown */
} A_Const;
/*
* TypeCast - a CAST expression
*/
typedef struct TypeCast
{
NodeTag type;
Node *arg; /* the expression being casted */
TypeName *typeName; /* the target type */
int location; /* token location, or -1 if unknown */
} TypeCast;
/*
* CollateClause - a COLLATE expression
*/
typedef struct CollateClause
{
NodeTag type;
Node *arg; /* input expression */
List *collname; /* possibly-qualified collation name */
int location; /* token location, or -1 if unknown */
} CollateClause;
/*
* FuncCall - a function or aggregate invocation
*
Support ordered-set (WITHIN GROUP) aggregates. This patch introduces generic support for ordered-set and hypothetical-set aggregate functions, as well as implementations of the instances defined in SQL:2008 (percentile_cont(), percentile_disc(), rank(), dense_rank(), percent_rank(), cume_dist()). We also added mode() though it is not in the spec, as well as versions of percentile_cont() and percentile_disc() that can compute multiple percentile values in one pass over the data. Unlike the original submission, this patch puts full control of the sorting process in the hands of the aggregate's support functions. To allow the support functions to find out how they're supposed to sort, a new API function AggGetAggref() is added to nodeAgg.c. This allows retrieval of the aggregate call's Aggref node, which may have other uses beyond the immediate need. There is also support for ordered-set aggregates to install cleanup callback functions, so that they can be sure that infrastructure such as tuplesort objects gets cleaned up. In passing, make some fixes in the recently-added support for variadic aggregates, and make some editorial adjustments in the recent FILTER additions for aggregates. Also, simplify use of IsBinaryCoercible() by allowing it to succeed whenever the target type is ANY or ANYELEMENT. It was inconsistent that it dealt with other polymorphic target types but not these. Atri Sharma and Andrew Gierth; reviewed by Pavel Stehule and Vik Fearing, and rather heavily editorialized upon by Tom Lane
2013-12-23 22:11:35 +01:00
* agg_order (if not NIL) indicates we saw 'foo(... ORDER BY ...)', or if
* agg_within_group is true, it was 'foo(...) WITHIN GROUP (ORDER BY ...)'.
* agg_star indicates we saw a 'foo(*)' construct, while agg_distinct
* indicates we saw 'foo(DISTINCT ...)'. In any of these cases, the
* construct *must* be an aggregate call. Otherwise, it might be either an
* aggregate or some other kind of function. However, if FILTER or OVER is
* present it had better be an aggregate or window function.
*
* Normally, you'd initialize this via makeFuncCall() and then only change the
* parts of the struct its defaults don't match afterwards, as needed.
*/
typedef struct FuncCall
{
NodeTag type;
List *funcname; /* qualified name of function */
List *args; /* the arguments (list of exprs) */
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List *agg_order; /* ORDER BY (list of SortBy) */
Node *agg_filter; /* FILTER clause, if any */
Support ordered-set (WITHIN GROUP) aggregates. This patch introduces generic support for ordered-set and hypothetical-set aggregate functions, as well as implementations of the instances defined in SQL:2008 (percentile_cont(), percentile_disc(), rank(), dense_rank(), percent_rank(), cume_dist()). We also added mode() though it is not in the spec, as well as versions of percentile_cont() and percentile_disc() that can compute multiple percentile values in one pass over the data. Unlike the original submission, this patch puts full control of the sorting process in the hands of the aggregate's support functions. To allow the support functions to find out how they're supposed to sort, a new API function AggGetAggref() is added to nodeAgg.c. This allows retrieval of the aggregate call's Aggref node, which may have other uses beyond the immediate need. There is also support for ordered-set aggregates to install cleanup callback functions, so that they can be sure that infrastructure such as tuplesort objects gets cleaned up. In passing, make some fixes in the recently-added support for variadic aggregates, and make some editorial adjustments in the recent FILTER additions for aggregates. Also, simplify use of IsBinaryCoercible() by allowing it to succeed whenever the target type is ANY or ANYELEMENT. It was inconsistent that it dealt with other polymorphic target types but not these. Atri Sharma and Andrew Gierth; reviewed by Pavel Stehule and Vik Fearing, and rather heavily editorialized upon by Tom Lane
2013-12-23 22:11:35 +01:00
bool agg_within_group; /* ORDER BY appeared in WITHIN GROUP */
bool agg_star; /* argument was really '*' */
bool agg_distinct; /* arguments were labeled DISTINCT */
bool func_variadic; /* last argument was labeled VARIADIC */
struct WindowDef *over; /* OVER clause, if any */
int location; /* token location, or -1 if unknown */
} FuncCall;
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/*
* A_Star - '*' representing all columns of a table or compound field
*
* This can appear within ColumnRef.fields, A_Indirection.indirection, and
* ResTarget.indirection lists.
*/
typedef struct A_Star
{
NodeTag type;
} A_Star;
/*
* A_Indices - array subscript or slice bounds ([lidx:uidx] or [uidx])
*/
typedef struct A_Indices
{
NodeTag type;
Node *lidx; /* NULL if it's a single subscript */
Node *uidx;
} A_Indices;
/*
* A_Indirection - select a field and/or array element from an expression
*
* The indirection list can contain A_Indices nodes (representing
* subscripting), string Value nodes (representing field selection --- the
* string value is the name of the field to select), and A_Star nodes
* (representing selection of all fields of a composite type).
* For example, a complex selection operation like
* (foo).field1[42][7].field2
* would be represented with a single A_Indirection node having a 4-element
* indirection list.
*
* Currently, A_Star must appear only as the last list element --- the grammar
* is responsible for enforcing this!
*/
typedef struct A_Indirection
{
NodeTag type;
Node *arg; /* the thing being selected from */
List *indirection; /* subscripts and/or field names and/or * */
} A_Indirection;
/*
* A_ArrayExpr - an ARRAY[] construct
*/
typedef struct A_ArrayExpr
{
NodeTag type;
List *elements; /* array element expressions */
int location; /* token location, or -1 if unknown */
} A_ArrayExpr;
/*
* ResTarget -
* result target (used in target list of pre-transformed parse trees)
*
* In a SELECT target list, 'name' is the column label from an
* 'AS ColumnLabel' clause, or NULL if there was none, and 'val' is the
* value expression itself. The 'indirection' field is not used.
*
* INSERT uses ResTarget in its target-column-names list. Here, 'name' is
* the name of the destination column, 'indirection' stores any subscripts
* attached to the destination, and 'val' is not used.
*
* In an UPDATE target list, 'name' is the name of the destination column,
* 'indirection' stores any subscripts attached to the destination, and
* 'val' is the expression to assign.
*
* See A_Indirection for more info about what can appear in 'indirection'.
*/
typedef struct ResTarget
{
NodeTag type;
char *name; /* column name or NULL */
List *indirection; /* subscripts, field names, and '*', or NIL */
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Node *val; /* the value expression to compute or assign */
int location; /* token location, or -1 if unknown */
} ResTarget;
/*
* MultiAssignRef - element of a row source expression for UPDATE
*
* In an UPDATE target list, when we have SET (a,b,c) = row-valued-expression,
* we generate separate ResTarget items for each of a,b,c. Their "val" trees
* are MultiAssignRef nodes numbered 1..n, linking to a common copy of the
* row-valued-expression (which parse analysis will process only once, when
* handling the MultiAssignRef with colno=1).
*/
typedef struct MultiAssignRef
{
NodeTag type;
Node *source; /* the row-valued expression */
int colno; /* column number for this target (1..n) */
int ncolumns; /* number of targets in the construct */
} MultiAssignRef;
/*
* SortBy - for ORDER BY clause
*/
typedef struct SortBy
{
NodeTag type;
Node *node; /* expression to sort on */
SortByDir sortby_dir; /* ASC/DESC/USING/default */
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SortByNulls sortby_nulls; /* NULLS FIRST/LAST */
List *useOp; /* name of op to use, if SORTBY_USING */
int location; /* operator location, or -1 if none/unknown */
} SortBy;
/*
* WindowDef - raw representation of WINDOW and OVER clauses
*
* For entries in a WINDOW list, "name" is the window name being defined.
* For OVER clauses, we use "name" for the "OVER window" syntax, or "refname"
* for the "OVER (window)" syntax, which is subtly different --- the latter
* implies overriding the window frame clause.
*/
typedef struct WindowDef
{
NodeTag type;
char *name; /* window's own name */
char *refname; /* referenced window name, if any */
List *partitionClause; /* PARTITION BY expression list */
List *orderClause; /* ORDER BY (list of SortBy) */
int frameOptions; /* frame_clause options, see below */
Node *startOffset; /* expression for starting bound, if any */
Node *endOffset; /* expression for ending bound, if any */
int location; /* parse location, or -1 if none/unknown */
} WindowDef;
/*
* frameOptions is an OR of these bits. The NONDEFAULT and BETWEEN bits are
* used so that ruleutils.c can tell which properties were specified and
* which were defaulted; the correct behavioral bits must be set either way.
* The START_foo and END_foo options must come in pairs of adjacent bits for
* the convenience of gram.y, even though some of them are useless/invalid.
* We will need more bits (and fields) to cover the full SQL:2008 option set.
*/
#define FRAMEOPTION_NONDEFAULT 0x00001 /* any specified? */
#define FRAMEOPTION_RANGE 0x00002 /* RANGE behavior */
#define FRAMEOPTION_ROWS 0x00004 /* ROWS behavior */
#define FRAMEOPTION_BETWEEN 0x00008 /* BETWEEN given? */
#define FRAMEOPTION_START_UNBOUNDED_PRECEDING 0x00010 /* start is U. P. */
#define FRAMEOPTION_END_UNBOUNDED_PRECEDING 0x00020 /* (disallowed) */
#define FRAMEOPTION_START_UNBOUNDED_FOLLOWING 0x00040 /* (disallowed) */
#define FRAMEOPTION_END_UNBOUNDED_FOLLOWING 0x00080 /* end is U. F. */
#define FRAMEOPTION_START_CURRENT_ROW 0x00100 /* start is C. R. */
#define FRAMEOPTION_END_CURRENT_ROW 0x00200 /* end is C. R. */
#define FRAMEOPTION_START_VALUE_PRECEDING 0x00400 /* start is V. P. */
#define FRAMEOPTION_END_VALUE_PRECEDING 0x00800 /* end is V. P. */
#define FRAMEOPTION_START_VALUE_FOLLOWING 0x01000 /* start is V. F. */
#define FRAMEOPTION_END_VALUE_FOLLOWING 0x02000 /* end is V. F. */
#define FRAMEOPTION_START_VALUE \
(FRAMEOPTION_START_VALUE_PRECEDING | FRAMEOPTION_START_VALUE_FOLLOWING)
#define FRAMEOPTION_END_VALUE \
(FRAMEOPTION_END_VALUE_PRECEDING | FRAMEOPTION_END_VALUE_FOLLOWING)
#define FRAMEOPTION_DEFAULTS \
(FRAMEOPTION_RANGE | FRAMEOPTION_START_UNBOUNDED_PRECEDING | \
FRAMEOPTION_END_CURRENT_ROW)
/*
* RangeSubselect - subquery appearing in a FROM clause
*/
typedef struct RangeSubselect
{
NodeTag type;
bool lateral; /* does it have LATERAL prefix? */
Node *subquery; /* the untransformed sub-select clause */
Alias *alias; /* table alias & optional column aliases */
} RangeSubselect;
/*
* RangeFunction - function call appearing in a FROM clause
*
* functions is a List because we use this to represent the construct
* ROWS FROM(func1(...), func2(...), ...). Each element of this list is a
* two-element sublist, the first element being the untransformed function
* call tree, and the second element being a possibly-empty list of ColumnDef
* nodes representing any columndef list attached to that function within the
* ROWS FROM() syntax.
*
* alias and coldeflist represent any alias and/or columndef list attached
* at the top level. (We disallow coldeflist appearing both here and
* per-function, but that's checked in parse analysis, not by the grammar.)
*/
typedef struct RangeFunction
{
NodeTag type;
bool lateral; /* does it have LATERAL prefix? */
bool ordinality; /* does it have WITH ORDINALITY suffix? */
bool is_rowsfrom; /* is result of ROWS FROM() syntax? */
List *functions; /* per-function information, see above */
Alias *alias; /* table alias & optional column aliases */
2006-10-04 02:30:14 +02:00
List *coldeflist; /* list of ColumnDef nodes to describe result
* of function returning RECORD */
} RangeFunction;
/*
* ColumnDef - column definition (used in various creates)
*
* If the column has a default value, we may have the value expression
* in either "raw" form (an untransformed parse tree) or "cooked" form
* (a post-parse-analysis, executable expression tree), depending on
* how this ColumnDef node was created (by parsing, or by inheritance
* from an existing relation). We should never have both in the same node!
*
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
* Similarly, we may have a COLLATE specification in either raw form
* (represented as a CollateClause with arg==NULL) or cooked form
* (the collation's OID).
*
* The constraints list may contain a CONSTR_DEFAULT item in a raw
* parsetree produced by gram.y, but transformCreateStmt will remove
* the item and set raw_default instead. CONSTR_DEFAULT items
* should not appear in any subsequent processing.
*/
typedef struct ColumnDef
{
NodeTag type;
char *colname; /* name of column */
TypeName *typeName; /* type of column */
int inhcount; /* number of times column is inherited */
bool is_local; /* column has local (non-inherited) def'n */
bool is_not_null; /* NOT NULL constraint specified? */
bool is_from_type; /* column definition came from table type */
char storage; /* attstorage setting, or 0 for default */
2005-10-15 04:49:52 +02:00
Node *raw_default; /* default value (untransformed parse tree) */
Node *cooked_default; /* default value (transformed expr tree) */
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
CollateClause *collClause; /* untransformed COLLATE spec, if any */
Oid collOid; /* collation OID (InvalidOid if not set) */
List *constraints; /* other constraints on column */
List *fdwoptions; /* per-column FDW options */
int location; /* parse location, or -1 if none/unknown */
} ColumnDef;
/*
* TableLikeClause - CREATE TABLE ( ... LIKE ... ) clause
*/
typedef struct TableLikeClause
{
NodeTag type;
RangeVar *relation;
bits32 options; /* OR of TableLikeOption flags */
} TableLikeClause;
typedef enum TableLikeOption
{
2010-02-26 03:01:40 +01:00
CREATE_TABLE_LIKE_DEFAULTS = 1 << 0,
CREATE_TABLE_LIKE_CONSTRAINTS = 1 << 1,
CREATE_TABLE_LIKE_INDEXES = 1 << 2,
CREATE_TABLE_LIKE_STORAGE = 1 << 3,
CREATE_TABLE_LIKE_COMMENTS = 1 << 4,
CREATE_TABLE_LIKE_ALL = 0x7FFFFFFF
} TableLikeOption;
/*
* IndexElem - index parameters (used in CREATE INDEX)
*
* For a plain index attribute, 'name' is the name of the table column to
* index, and 'expr' is NULL. For an index expression, 'name' is NULL and
* 'expr' is the expression tree.
*/
typedef struct IndexElem
{
NodeTag type;
char *name; /* name of attribute to index, or NULL */
Node *expr; /* expression to index, or NULL */
char *indexcolname; /* name for index column; NULL = default */
List *collation; /* name of collation; NIL = default */
List *opclass; /* name of desired opclass; NIL = default */
SortByDir ordering; /* ASC/DESC/default */
2007-11-15 22:14:46 +01:00
SortByNulls nulls_ordering; /* FIRST/LAST/default */
} IndexElem;
/*
* DefElem - a generic "name = value" option definition
*
* In some contexts the name can be qualified. Also, certain SQL commands
* allow a SET/ADD/DROP action to be attached to option settings, so it's
* convenient to carry a field for that too. (Note: currently, it is our
* practice that the grammar allows namespace and action only in statements
* where they are relevant; C code can just ignore those fields in other
* statements.)
*/
typedef enum DefElemAction
{
DEFELEM_UNSPEC, /* no action given */
DEFELEM_SET,
DEFELEM_ADD,
DEFELEM_DROP
} DefElemAction;
typedef struct DefElem
{
NodeTag type;
char *defnamespace; /* NULL if unqualified name */
char *defname;
Node *arg; /* a (Value *) or a (TypeName *) */
DefElemAction defaction; /* unspecified action, or SET/ADD/DROP */
} DefElem;
/*
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
* LockingClause - raw representation of FOR [NO KEY] UPDATE/[KEY] SHARE
* options
*
* Note: lockedRels == NIL means "all relations in query". Otherwise it
* is a list of RangeVar nodes. (We use RangeVar mainly because it carries
* a location field --- currently, parse analysis insists on unqualified
* names in LockingClause.)
*/
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
typedef enum LockClauseStrength
{
/* order is important -- see applyLockingClause */
LCS_FORKEYSHARE,
LCS_FORSHARE,
LCS_FORNOKEYUPDATE,
LCS_FORUPDATE
} LockClauseStrength;
typedef struct LockingClause
{
NodeTag type;
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
List *lockedRels; /* FOR [KEY] UPDATE/SHARE relations */
LockClauseStrength strength;
LockWaitPolicy waitPolicy; /* NOWAIT and SKIP LOCKED */
} LockingClause;
/*
* XMLSERIALIZE (in raw parse tree only)
*/
typedef struct XmlSerialize
{
NodeTag type;
XmlOptionType xmloption; /* DOCUMENT or CONTENT */
Node *expr;
TypeName *typeName;
int location; /* token location, or -1 if unknown */
} XmlSerialize;
1997-04-02 05:34:46 +02:00
/****************************************************************************
* Nodes for a Query tree
****************************************************************************/
1997-04-02 05:34:46 +02:00
/*--------------------
* RangeTblEntry -
* A range table is a List of RangeTblEntry nodes.
*
* A range table entry may represent a plain relation, a sub-select in
* FROM, or the result of a JOIN clause. (Only explicit JOIN syntax
* produces an RTE, not the implicit join resulting from multiple FROM
* items. This is because we only need the RTE to deal with SQL features
* like outer joins and join-output-column aliasing.) Other special
* RTE types also exist, as indicated by RTEKind.
*
* Note that we consider RTE_RELATION to cover anything that has a pg_class
* entry. relkind distinguishes the sub-cases.
*
* alias is an Alias node representing the AS alias-clause attached to the
* FROM expression, or NULL if no clause.
*
* eref is the table reference name and column reference names (either
* real or aliases). Note that system columns (OID etc) are not included
* in the column list.
* eref->aliasname is required to be present, and should generally be used
* to identify the RTE for error messages etc.
*
* In RELATION RTEs, the colnames in both alias and eref are indexed by
* physical attribute number; this means there must be colname entries for
* dropped columns. When building an RTE we insert empty strings ("") for
* dropped columns. Note however that a stored rule may have nonempty
* colnames for columns dropped since the rule was created (and for that
* matter the colnames might be out of date due to column renamings).
* The same comments apply to FUNCTION RTEs when a function's return type
* is a named composite type.
*
* In JOIN RTEs, the colnames in both alias and eref are one-to-one with
* joinaliasvars entries. A JOIN RTE will omit columns of its inputs when
* those columns are known to be dropped at parse time. Again, however,
* a stored rule might contain entries for columns dropped since the rule
* was created. (This is only possible for columns not actually referenced
* in the rule.) When loading a stored rule, we replace the joinaliasvars
* items for any such columns with null pointers. (We can't simply delete
* them from the joinaliasvars list, because that would affect the attnums
* of Vars referencing the rest of the list.)
*
* inh is TRUE for relation references that should be expanded to include
* inheritance children, if the rel has any. This *must* be FALSE for
* RTEs other than RTE_RELATION entries.
*
* inFromCl marks those range variables that are listed in the FROM clause.
* It's false for RTEs that are added to a query behind the scenes, such
* as the NEW and OLD variables for a rule, or the subqueries of a UNION.
* This flag is not used anymore during parsing, since the parser now uses
* a separate "namespace" data structure to control visibility, but it is
* needed by ruleutils.c to determine whether RTEs should be shown in
* decompiled queries.
*
* requiredPerms and checkAsUser specify run-time access permissions
* checks to be performed at query startup. The user must have *all*
* of the permissions that are OR'd together in requiredPerms (zero
* indicates no permissions checking). If checkAsUser is not zero,
* then do the permissions checks using the access rights of that user,
* not the current effective user ID. (This allows rules to act as
* setuid gateways.) Permissions checks only apply to RELATION RTEs.
*
* For SELECT/INSERT/UPDATE permissions, if the user doesn't have
* table-wide permissions then it is sufficient to have the permissions
* on all columns identified in selectedCols (for SELECT) and/or
* modifiedCols (for INSERT/UPDATE; we can tell which from the query type).
* selectedCols and modifiedCols are bitmapsets, which cannot have negative
* integer members, so we subtract FirstLowInvalidHeapAttributeNumber from
* column numbers before storing them in these fields. A whole-row Var
* reference is represented by setting the bit for InvalidAttrNumber.
*--------------------
*/
typedef enum RTEKind
{
RTE_RELATION, /* ordinary relation reference */
RTE_SUBQUERY, /* subquery in FROM */
RTE_JOIN, /* join */
RTE_FUNCTION, /* function in FROM */
RTE_VALUES, /* VALUES (<exprlist>), (<exprlist>), ... */
RTE_CTE /* common table expr (WITH list element) */
} RTEKind;
typedef struct RangeTblEntry
{
NodeTag type;
RTEKind rtekind; /* see above */
/*
2005-10-15 04:49:52 +02:00
* XXX the fields applicable to only some rte kinds should be merged into
* a union. I didn't do this yet because the diffs would impact a lot of
* code that is being actively worked on. FIXME someday.
*/
/*
* Fields valid for a plain relation RTE (else zero):
*/
Oid relid; /* OID of the relation */
char relkind; /* relation kind (see pg_class.relkind) */
/*
* Fields valid for a subquery RTE (else NULL):
*/
Query *subquery; /* the sub-query */
bool security_barrier; /* is from security_barrier view? */
/*
* Fields valid for a join RTE (else NULL/zero):
*
* joinaliasvars is a list of (usually) Vars corresponding to the columns
* of the join result. An alias Var referencing column K of the join
* result can be replaced by the K'th element of joinaliasvars --- but to
* simplify the task of reverse-listing aliases correctly, we do not do
* that until planning time. In detail: an element of joinaliasvars can
* be a Var of one of the join's input relations, or such a Var with an
* implicit coercion to the join's output column type, or a COALESCE
* expression containing the two input column Vars (possibly coerced).
* Within a Query loaded from a stored rule, it is also possible for
* joinaliasvars items to be null pointers, which are placeholders for
* (necessarily unreferenced) columns dropped since the rule was made.
* Also, once planning begins, joinaliasvars items can be almost anything,
* as a result of subquery-flattening substitutions.
*/
JoinType jointype; /* type of join */
List *joinaliasvars; /* list of alias-var expansions */
/*
* Fields valid for a function RTE (else NIL/zero):
*
* When funcordinality is true, the eref->colnames list includes an alias
* for the ordinality column. The ordinality column is otherwise
* implicit, and must be accounted for "by hand" in places such as
* expandRTE().
*/
List *functions; /* list of RangeTblFunction nodes */
bool funcordinality; /* is this called WITH ORDINALITY? */
/*
* Fields valid for a values RTE (else NIL):
*/
List *values_lists; /* list of expression lists */
List *values_collations; /* OID list of column collation OIDs */
/*
* Fields valid for a CTE RTE (else NULL/zero):
*/
char *ctename; /* name of the WITH list item */
Index ctelevelsup; /* number of query levels up */
bool self_reference; /* is this a recursive self-reference? */
List *ctecoltypes; /* OID list of column type OIDs */
List *ctecoltypmods; /* integer list of column typmods */
2011-04-10 17:42:00 +02:00
List *ctecolcollations; /* OID list of column collation OIDs */
/*
* Fields valid in all RTEs:
*/
Alias *alias; /* user-written alias clause, if any */
Alias *eref; /* expanded reference names */
bool lateral; /* subquery, function, or values is LATERAL? */
bool inh; /* inheritance requested? */
bool inFromCl; /* present in FROM clause? */
AclMode requiredPerms; /* bitmask of required access permissions */
Oid checkAsUser; /* if valid, check access as this role */
Bitmapset *selectedCols; /* columns needing SELECT permission */
Bitmapset *modifiedCols; /* columns needing INSERT/UPDATE permission */
List *securityQuals; /* any security barrier quals to apply */
} RangeTblEntry;
/*
* RangeTblFunction -
* RangeTblEntry subsidiary data for one function in a FUNCTION RTE.
*
* If the function had a column definition list (required for an
* otherwise-unspecified RECORD result), funccolnames lists the names given
* in the definition list, funccoltypes lists their declared column types,
* funccoltypmods lists their typmods, funccolcollations their collations.
* Otherwise, those fields are NIL.
*
* Notice we don't attempt to store info about the results of functions
* returning named composite types, because those can change from time to
* time. We do however remember how many columns we thought the type had
* (including dropped columns!), so that we can successfully ignore any
* columns added after the query was parsed.
*/
typedef struct RangeTblFunction
{
NodeTag type;
Node *funcexpr; /* expression tree for func call */
int funccolcount; /* number of columns it contributes to RTE */
/* These fields record the contents of a column definition list, if any: */
List *funccolnames; /* column names (list of String) */
List *funccoltypes; /* OID list of column type OIDs */
List *funccoltypmods; /* integer list of column typmods */
List *funccolcollations; /* OID list of column collation OIDs */
/* This is set during planning for use by the executor: */
Bitmapset *funcparams; /* PARAM_EXEC Param IDs affecting this func */
} RangeTblFunction;
/*
* WithCheckOption -
* representation of WITH CHECK OPTION checks to be applied to new tuples
* when inserting/updating an auto-updatable view.
*/
typedef struct WithCheckOption
{
NodeTag type;
char *viewname; /* name of view that specified the WCO */
Node *qual; /* constraint qual to check */
bool cascaded; /* true = WITH CASCADED CHECK OPTION */
} WithCheckOption;
/*
* SortGroupClause -
* representation of ORDER BY, GROUP BY, PARTITION BY,
* DISTINCT, DISTINCT ON items
*
* You might think that ORDER BY is only interested in defining ordering,
* and GROUP/DISTINCT are only interested in defining equality. However,
* one way to implement grouping is to sort and then apply a "uniq"-like
* filter. So it's also interesting to keep track of possible sort operators
* for GROUP/DISTINCT, and in particular to try to sort for the grouping
* in a way that will also yield a requested ORDER BY ordering. So we need
* to be able to compare ORDER BY and GROUP/DISTINCT lists, which motivates
* the decision to give them the same representation.
*
* tleSortGroupRef must match ressortgroupref of exactly one entry of the
* query's targetlist; that is the expression to be sorted or grouped by.
* eqop is the OID of the equality operator.
* sortop is the OID of the ordering operator (a "<" or ">" operator),
* or InvalidOid if not available.
* nulls_first means about what you'd expect. If sortop is InvalidOid
* then nulls_first is meaningless and should be set to false.
* hashable is TRUE if eqop is hashable (note this condition also depends
* on the datatype of the input expression).
*
* In an ORDER BY item, all fields must be valid. (The eqop isn't essential
* here, but it's cheap to get it along with the sortop, and requiring it
* to be valid eases comparisons to grouping items.) Note that this isn't
* actually enough information to determine an ordering: if the sortop is
* collation-sensitive, a collation OID is needed too. We don't store the
* collation in SortGroupClause because it's not available at the time the
* parser builds the SortGroupClause; instead, consult the exposed collation
* of the referenced targetlist expression to find out what it is.
*
* In a grouping item, eqop must be valid. If the eqop is a btree equality
* operator, then sortop should be set to a compatible ordering operator.
* We prefer to set eqop/sortop/nulls_first to match any ORDER BY item that
* the query presents for the same tlist item. If there is none, we just
* use the default ordering op for the datatype.
*
* If the tlist item's type has a hash opclass but no btree opclass, then
* we will set eqop to the hash equality operator, sortop to InvalidOid,
* and nulls_first to false. A grouping item of this kind can only be
* implemented by hashing, and of course it'll never match an ORDER BY item.
*
* The hashable flag is provided since we generally have the requisite
* information readily available when the SortGroupClause is constructed,
* and it's relatively expensive to get it again later. Note there is no
* need for a "sortable" flag since OidIsValid(sortop) serves the purpose.
*
* A query might have both ORDER BY and DISTINCT (or DISTINCT ON) clauses.
* In SELECT DISTINCT, the distinctClause list is as long or longer than the
* sortClause list, while in SELECT DISTINCT ON it's typically shorter.
* The two lists must match up to the end of the shorter one --- the parser
* rearranges the distinctClause if necessary to make this true. (This
* restriction ensures that only one sort step is needed to both satisfy the
* ORDER BY and set up for the Unique step. This is semantically necessary
* for DISTINCT ON, and presents no real drawback for DISTINCT.)
*/
typedef struct SortGroupClause
{
NodeTag type;
Index tleSortGroupRef; /* reference into targetlist */
Oid eqop; /* the equality operator ('=' op) */
Oid sortop; /* the ordering operator ('<' op), or 0 */
bool nulls_first; /* do NULLs come before normal values? */
bool hashable; /* can eqop be implemented by hashing? */
} SortGroupClause;
/*
* WindowClause -
* transformed representation of WINDOW and OVER clauses
*
* A parsed Query's windowClause list contains these structs. "name" is set
* if the clause originally came from WINDOW, and is NULL if it originally
* was an OVER clause (but note that we collapse out duplicate OVERs).
* partitionClause and orderClause are lists of SortGroupClause structs.
* winref is an ID number referenced by WindowFunc nodes; it must be unique
* among the members of a Query's windowClause list.
* When refname isn't null, the partitionClause is always copied from there;
* the orderClause might or might not be copied (see copiedOrder); the framing
* options are never copied, per spec.
*/
typedef struct WindowClause
{
NodeTag type;
char *name; /* window name (NULL in an OVER clause) */
char *refname; /* referenced window name, if any */
List *partitionClause; /* PARTITION BY list */
List *orderClause; /* ORDER BY list */
int frameOptions; /* frame_clause options, see WindowDef */
Node *startOffset; /* expression for starting bound, if any */
Node *endOffset; /* expression for ending bound, if any */
Index winref; /* ID referenced by window functions */
bool copiedOrder; /* did we copy orderClause from refname? */
} WindowClause;
/*
* RowMarkClause -
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
* parser output representation of FOR [KEY] UPDATE/SHARE clauses
*
* Query.rowMarks contains a separate RowMarkClause node for each relation
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
* identified as a FOR [KEY] UPDATE/SHARE target. If one of these clauses
* is applied to a subquery, we generate RowMarkClauses for all normal and
* subquery rels in the subquery, but they are marked pushedDown = true to
* distinguish them from clauses that were explicitly written at this query
* level. Also, Query.hasForUpdate tells whether there were explicit FOR
* UPDATE/SHARE/KEY SHARE clauses in the current query level.
*/
typedef struct RowMarkClause
{
NodeTag type;
Index rti; /* range table index of target relation */
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 16:04:59 +01:00
LockClauseStrength strength;
LockWaitPolicy waitPolicy; /* NOWAIT and SKIP LOCKED */
bool pushedDown; /* pushed down from higher query level? */
} RowMarkClause;
/*
* WithClause -
* representation of WITH clause
*
* Note: WithClause does not propagate into the Query representation;
* but CommonTableExpr does.
*/
typedef struct WithClause
{
NodeTag type;
List *ctes; /* list of CommonTableExprs */
bool recursive; /* true = WITH RECURSIVE */
int location; /* token location, or -1 if unknown */
} WithClause;
/*
* CommonTableExpr -
* representation of WITH list element
*
* We don't currently support the SEARCH or CYCLE clause.
*/
typedef struct CommonTableExpr
{
NodeTag type;
char *ctename; /* query name (never qualified) */
List *aliascolnames; /* optional list of column names */
/* SelectStmt/InsertStmt/etc before parse analysis, Query afterwards: */
Node *ctequery; /* the CTE's subquery */
int location; /* token location, or -1 if unknown */
/* These fields are set during parse analysis: */
bool cterecursive; /* is this CTE actually recursive? */
int cterefcount; /* number of RTEs referencing this CTE
* (excluding internal self-references) */
List *ctecolnames; /* list of output column names */
List *ctecoltypes; /* OID list of output column type OIDs */
List *ctecoltypmods; /* integer list of output column typmods */
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List *ctecolcollations; /* OID list of column collation OIDs */
} CommonTableExpr;
/* Convenience macro to get the output tlist of a CTE's query */
#define GetCTETargetList(cte) \
(AssertMacro(IsA((cte)->ctequery, Query)), \
((Query *) (cte)->ctequery)->commandType == CMD_SELECT ? \
((Query *) (cte)->ctequery)->targetList : \
((Query *) (cte)->ctequery)->returningList)
/*****************************************************************************
* Optimizable Statements
*****************************************************************************/
/* ----------------------
* Insert Statement
*
* The source expression is represented by SelectStmt for both the
* SELECT and VALUES cases. If selectStmt is NULL, then the query
* is INSERT ... DEFAULT VALUES.
* ----------------------
*/
typedef struct InsertStmt
{
NodeTag type;
RangeVar *relation; /* relation to insert into */
List *cols; /* optional: names of the target columns */
Node *selectStmt; /* the source SELECT/VALUES, or NULL */
List *returningList; /* list of expressions to return */
WithClause *withClause; /* WITH clause */
} InsertStmt;
/* ----------------------
* Delete Statement
* ----------------------
*/
typedef struct DeleteStmt
{
NodeTag type;
RangeVar *relation; /* relation to delete from */
List *usingClause; /* optional using clause for more tables */
Node *whereClause; /* qualifications */
List *returningList; /* list of expressions to return */
WithClause *withClause; /* WITH clause */
} DeleteStmt;
/* ----------------------
* Update Statement
* ----------------------
*/
typedef struct UpdateStmt
{
NodeTag type;
RangeVar *relation; /* relation to update */
List *targetList; /* the target list (of ResTarget) */
Node *whereClause; /* qualifications */
List *fromClause; /* optional from clause for more tables */
List *returningList; /* list of expressions to return */
WithClause *withClause; /* WITH clause */
} UpdateStmt;
/* ----------------------
* Select Statement
*
* A "simple" SELECT is represented in the output of gram.y by a single
* SelectStmt node; so is a VALUES construct. A query containing set
* operators (UNION, INTERSECT, EXCEPT) is represented by a tree of SelectStmt
* nodes, in which the leaf nodes are component SELECTs and the internal nodes
* represent UNION, INTERSECT, or EXCEPT operators. Using the same node
* type for both leaf and internal nodes allows gram.y to stick ORDER BY,
* LIMIT, etc, clause values into a SELECT statement without worrying
* whether it is a simple or compound SELECT.
* ----------------------
*/
typedef enum SetOperation
{
SETOP_NONE = 0,
SETOP_UNION,
SETOP_INTERSECT,
SETOP_EXCEPT
} SetOperation;
typedef struct SelectStmt
{
NodeTag type;
/*
* These fields are used only in "leaf" SelectStmts.
*/
List *distinctClause; /* NULL, list of DISTINCT ON exprs, or
2005-10-15 04:49:52 +02:00
* lcons(NIL,NIL) for all (SELECT DISTINCT) */
IntoClause *intoClause; /* target for SELECT INTO */
List *targetList; /* the target list (of ResTarget) */
List *fromClause; /* the FROM clause */
Node *whereClause; /* WHERE qualification */
List *groupClause; /* GROUP BY clauses */
Node *havingClause; /* HAVING conditional-expression */
List *windowClause; /* WINDOW window_name AS (...), ... */
/*
* In a "leaf" node representing a VALUES list, the above fields are all
2006-10-04 02:30:14 +02:00
* null, and instead this field is set. Note that the elements of the
* sublists are just expressions, without ResTarget decoration. Also note
* that a list element can be DEFAULT (represented as a SetToDefault
* node), regardless of the context of the VALUES list. It's up to parse
* analysis to reject that where not valid.
*/
List *valuesLists; /* untransformed list of expression lists */
/*
* These fields are used in both "leaf" SelectStmts and upper-level
* SelectStmts.
*/
List *sortClause; /* sort clause (a list of SortBy's) */
Node *limitOffset; /* # of result tuples to skip */
Node *limitCount; /* # of result tuples to return */
List *lockingClause; /* FOR UPDATE (list of LockingClause's) */
WithClause *withClause; /* WITH clause */
/*
* These fields are used only in upper-level SelectStmts.
*/
SetOperation op; /* type of set op */
bool all; /* ALL specified? */
struct SelectStmt *larg; /* left child */
struct SelectStmt *rarg; /* right child */
/* Eventually add fields for CORRESPONDING spec here */
} SelectStmt;
/* ----------------------
* Set Operation node for post-analysis query trees
*
* After parse analysis, a SELECT with set operations is represented by a
* top-level Query node containing the leaf SELECTs as subqueries in its
* range table. Its setOperations field shows the tree of set operations,
* with leaf SelectStmt nodes replaced by RangeTblRef nodes, and internal
* nodes replaced by SetOperationStmt nodes. Information about the output
* column types is added, too. (Note that the child nodes do not necessarily
* produce these types directly, but we've checked that their output types
* can be coerced to the output column type.) Also, if it's not UNION ALL,
* information about the types' sort/group semantics is provided in the form
* of a SortGroupClause list (same representation as, eg, DISTINCT).
* The resolved common column collations are provided too; but note that if
* it's not UNION ALL, it's okay for a column to not have a common collation,
* so a member of the colCollations list could be InvalidOid even though the
* column has a collatable type.
* ----------------------
*/
typedef struct SetOperationStmt
{
NodeTag type;
SetOperation op; /* type of set op */
bool all; /* ALL specified? */
Node *larg; /* left child */
Node *rarg; /* right child */
/* Eventually add fields for CORRESPONDING spec here */
/* Fields derived during parse analysis: */
List *colTypes; /* OID list of output column type OIDs */
List *colTypmods; /* integer list of output column typmods */
List *colCollations; /* OID list of output column collation OIDs */
List *groupClauses; /* a list of SortGroupClause's */
/* groupClauses is NIL if UNION ALL, but must be set otherwise */
} SetOperationStmt;
/*****************************************************************************
* Other Statements (no optimizations required)
*
* These are not touched by parser/analyze.c except to put them into
* the utilityStmt field of a Query. This is eventually passed to
* ProcessUtility (by-passing rewriting and planning). Some of the
* statements do need attention from parse analysis, and this is
* done by routines in parser/parse_utilcmd.c after ProcessUtility
* receives the command for execution.
*****************************************************************************/
2003-06-27 16:45:32 +02:00
/*
* When a command can act on several kinds of objects with only one
* parse structure required, use these constants to designate the
* object type. Note that commands typically don't support all the types.
2003-06-27 16:45:32 +02:00
*/
2003-08-04 02:43:34 +02:00
typedef enum ObjectType
{
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OBJECT_AGGREGATE,
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OBJECT_ATTRIBUTE, /* type's attribute, when distinct from column */
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OBJECT_CAST,
OBJECT_COLUMN,
OBJECT_COLLATION,
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OBJECT_CONVERSION,
OBJECT_DATABASE,
OBJECT_DEFAULT,
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OBJECT_DOMAIN,
OBJECT_DOMCONSTRAINT,
OBJECT_EVENT_TRIGGER,
OBJECT_EXTENSION,
OBJECT_FDW,
OBJECT_FOREIGN_SERVER,
OBJECT_FOREIGN_TABLE,
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OBJECT_FUNCTION,
OBJECT_INDEX,
OBJECT_LANGUAGE,
OBJECT_LARGEOBJECT,
OBJECT_MATVIEW,
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OBJECT_OPCLASS,
OBJECT_OPERATOR,
OBJECT_OPFAMILY,
Row-Level Security Policies (RLS) Building on the updatable security-barrier views work, add the ability to define policies on tables to limit the set of rows which are returned from a query and which are allowed to be added to a table. Expressions defined by the policy for filtering are added to the security barrier quals of the query, while expressions defined to check records being added to a table are added to the with-check options of the query. New top-level commands are CREATE/ALTER/DROP POLICY and are controlled by the table owner. Row Security is able to be enabled and disabled by the owner on a per-table basis using ALTER TABLE .. ENABLE/DISABLE ROW SECURITY. Per discussion, ROW SECURITY is disabled on tables by default and must be enabled for policies on the table to be used. If no policies exist on a table with ROW SECURITY enabled, a default-deny policy is used and no records will be visible. By default, row security is applied at all times except for the table owner and the superuser. A new GUC, row_security, is added which can be set to ON, OFF, or FORCE. When set to FORCE, row security will be applied even for the table owner and superusers. When set to OFF, row security will be disabled when allowed and an error will be thrown if the user does not have rights to bypass row security. Per discussion, pg_dump sets row_security = OFF by default to ensure that exports and backups will have all data in the table or will error if there are insufficient privileges to bypass row security. A new option has been added to pg_dump, --enable-row-security, to ask pg_dump to export with row security enabled. A new role capability, BYPASSRLS, which can only be set by the superuser, is added to allow other users to be able to bypass row security using row_security = OFF. Many thanks to the various individuals who have helped with the design, particularly Robert Haas for his feedback. Authors include Craig Ringer, KaiGai Kohei, Adam Brightwell, Dean Rasheed, with additional changes and rework by me. Reviewers have included all of the above, Greg Smith, Jeff McCormick, and Robert Haas.
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OBJECT_POLICY,
OBJECT_ROLE,
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OBJECT_RULE,
OBJECT_SCHEMA,
OBJECT_SEQUENCE,
OBJECT_TABCONSTRAINT,
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OBJECT_TABLE,
OBJECT_TABLESPACE,
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OBJECT_TRIGGER,
OBJECT_TSCONFIGURATION,
OBJECT_TSDICTIONARY,
OBJECT_TSPARSER,
OBJECT_TSTEMPLATE,
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OBJECT_TYPE,
OBJECT_VIEW
} ObjectType;
2003-06-27 16:45:32 +02:00
/* ----------------------
* Create Schema Statement
*
* NOTE: the schemaElts list contains raw parsetrees for component statements
* of the schema, such as CREATE TABLE, GRANT, etc. These are analyzed and
* executed after the schema itself is created.
* ----------------------
*/
typedef struct CreateSchemaStmt
{
NodeTag type;
char *schemaname; /* the name of the schema to create */
char *authid; /* the owner of the created schema */
List *schemaElts; /* schema components (list of parsenodes) */
bool if_not_exists; /* just do nothing if schema already exists? */
} CreateSchemaStmt;
typedef enum DropBehavior
{
DROP_RESTRICT, /* drop fails if any dependent objects */
DROP_CASCADE /* remove dependent objects too */
} DropBehavior;
/* ----------------------
* Alter Table
* ----------------------
*/
typedef struct AlterTableStmt
{
NodeTag type;
RangeVar *relation; /* table to work on */
List *cmds; /* list of subcommands */
ObjectType relkind; /* type of object */
bool missing_ok; /* skip error if table missing */
} AlterTableStmt;
typedef enum AlterTableType
{
AT_AddColumn, /* add column */
AT_AddColumnRecurse, /* internal to commands/tablecmds.c */
AT_AddColumnToView, /* implicitly via CREATE OR REPLACE VIEW */
AT_ColumnDefault, /* alter column default */
AT_DropNotNull, /* alter column drop not null */
AT_SetNotNull, /* alter column set not null */
AT_SetStatistics, /* alter column set statistics */
AT_SetOptions, /* alter column set ( options ) */
AT_ResetOptions, /* alter column reset ( options ) */
AT_SetStorage, /* alter column set storage */
AT_DropColumn, /* drop column */
AT_DropColumnRecurse, /* internal to commands/tablecmds.c */
AT_AddIndex, /* add index */
AT_ReAddIndex, /* internal to commands/tablecmds.c */
AT_AddConstraint, /* add constraint */
AT_AddConstraintRecurse, /* internal to commands/tablecmds.c */
AT_ReAddConstraint, /* internal to commands/tablecmds.c */
AT_AlterConstraint, /* alter constraint */
AT_ValidateConstraint, /* validate constraint */
AT_ValidateConstraintRecurse, /* internal to commands/tablecmds.c */
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AT_ProcessedConstraint, /* pre-processed add constraint (local in
* parser/parse_utilcmd.c) */
AT_AddIndexConstraint, /* add constraint using existing index */
AT_DropConstraint, /* drop constraint */
AT_DropConstraintRecurse, /* internal to commands/tablecmds.c */
AT_AlterColumnType, /* alter column type */
AT_AlterColumnGenericOptions, /* alter column OPTIONS (...) */
AT_ChangeOwner, /* change owner */
AT_ClusterOn, /* CLUSTER ON */
AT_DropCluster, /* SET WITHOUT CLUSTER */
AT_SetLogged, /* SET LOGGED */
AT_SetUnLogged, /* SET UNLOGGED */
AT_AddOids, /* SET WITH OIDS */
AT_AddOidsRecurse, /* internal to commands/tablecmds.c */
AT_DropOids, /* SET WITHOUT OIDS */
AT_SetTableSpace, /* SET TABLESPACE */
AT_SetRelOptions, /* SET (...) -- AM specific parameters */
AT_ResetRelOptions, /* RESET (...) -- AM specific parameters */
AT_ReplaceRelOptions, /* replace reloption list in its entirety */
AT_EnableTrig, /* ENABLE TRIGGER name */
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
AT_EnableAlwaysTrig, /* ENABLE ALWAYS TRIGGER name */
AT_EnableReplicaTrig, /* ENABLE REPLICA TRIGGER name */
AT_DisableTrig, /* DISABLE TRIGGER name */
AT_EnableTrigAll, /* ENABLE TRIGGER ALL */
AT_DisableTrigAll, /* DISABLE TRIGGER ALL */
AT_EnableTrigUser, /* ENABLE TRIGGER USER */
ALTER TABLE ... ADD/DROPS INHERIT (actually INHERIT / NO INHERIT) Open items: There were a few tangentially related issues that have come up that I think are TODOs. I'm likely to tackle one or two of these next so I'm interested in hearing feedback on them as well. . Constraints currently do not know anything about inheritance. Tom suggested adding a coninhcount and conislocal like attributes have to track their inheritance status. . Foreign key constraints currently do not get copied to new children (and therefore my code doesn't verify them). I don't think it would be hard to add them and treat them like CHECK constraints. . No constraints at all are copied to tables defined with LIKE. That makes it hard to use LIKE to define new partitions. The standard defines LIKE and specifically says it does not copy constraints. But the standard already has an option called INCLUDING DEFAULTS; we could always define a non-standard extension LIKE table INCLUDING CONSTRAINTS that gives the user the option to request a copy including constraints. . Personally, I think the whole attislocal thing is bunk. The decision about whether to drop a column from children tables or not is something that should be up to the user and trying to DWIM based on whether there was ever a local definition or the column was acquired purely through inheritance is hardly ever going to match up with user expectations. . And of course there's the whole unique and primary key constraint issue. I think to get any traction at all on this you have a prerequisite of a real partitioned table implementation where the system knows what the partition key is so it can recognize when it's a leading part of an index key. Greg Stark
2006-07-02 03:58:36 +02:00
AT_DisableTrigUser, /* DISABLE TRIGGER USER */
Changes pg_trigger and extend pg_rewrite in order to allow triggers and rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
2007-03-20 00:38:32 +01:00
AT_EnableRule, /* ENABLE RULE name */
AT_EnableAlwaysRule, /* ENABLE ALWAYS RULE name */
AT_EnableReplicaRule, /* ENABLE REPLICA RULE name */
AT_DisableRule, /* DISABLE RULE name */
AT_AddInherit, /* INHERIT parent */
AT_DropInherit, /* NO INHERIT parent */
AT_AddOf, /* OF <type_name> */
AT_DropOf, /* NOT OF */
AT_ReplicaIdentity, /* REPLICA IDENTITY */
Row-Level Security Policies (RLS) Building on the updatable security-barrier views work, add the ability to define policies on tables to limit the set of rows which are returned from a query and which are allowed to be added to a table. Expressions defined by the policy for filtering are added to the security barrier quals of the query, while expressions defined to check records being added to a table are added to the with-check options of the query. New top-level commands are CREATE/ALTER/DROP POLICY and are controlled by the table owner. Row Security is able to be enabled and disabled by the owner on a per-table basis using ALTER TABLE .. ENABLE/DISABLE ROW SECURITY. Per discussion, ROW SECURITY is disabled on tables by default and must be enabled for policies on the table to be used. If no policies exist on a table with ROW SECURITY enabled, a default-deny policy is used and no records will be visible. By default, row security is applied at all times except for the table owner and the superuser. A new GUC, row_security, is added which can be set to ON, OFF, or FORCE. When set to FORCE, row security will be applied even for the table owner and superusers. When set to OFF, row security will be disabled when allowed and an error will be thrown if the user does not have rights to bypass row security. Per discussion, pg_dump sets row_security = OFF by default to ensure that exports and backups will have all data in the table or will error if there are insufficient privileges to bypass row security. A new option has been added to pg_dump, --enable-row-security, to ask pg_dump to export with row security enabled. A new role capability, BYPASSRLS, which can only be set by the superuser, is added to allow other users to be able to bypass row security using row_security = OFF. Many thanks to the various individuals who have helped with the design, particularly Robert Haas for his feedback. Authors include Craig Ringer, KaiGai Kohei, Adam Brightwell, Dean Rasheed, with additional changes and rework by me. Reviewers have included all of the above, Greg Smith, Jeff McCormick, and Robert Haas.
2014-09-19 17:18:35 +02:00
AT_EnableRowSecurity, /* ENABLE ROW SECURITY */
AT_DisableRowSecurity, /* DISABLE ROW SECURITY */
AT_GenericOptions /* OPTIONS (...) */
} AlterTableType;
typedef struct ReplicaIdentityStmt
{
NodeTag type;
char identity_type;
char *name;
} ReplicaIdentityStmt;
typedef struct AlterTableCmd /* one subcommand of an ALTER TABLE */
{
NodeTag type;
AlterTableType subtype; /* Type of table alteration to apply */
char *name; /* column, constraint, or trigger to act on,
* or new owner or tablespace */
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
Node *def; /* definition of new column, index,
* constraint, or parent table */
DropBehavior behavior; /* RESTRICT or CASCADE for DROP cases */
bool missing_ok; /* skip error if missing? */
} AlterTableCmd;
2002-12-06 06:00:34 +01:00
/* ----------------------
* Alter Domain
*
* The fields are used in different ways by the different variants of
* this command.
2002-12-06 06:00:34 +01:00
* ----------------------
*/
typedef struct AlterDomainStmt
{
NodeTag type;
char subtype; /*------------
* T = alter column default
* N = alter column drop not null
* O = alter column set not null
* C = add constraint
* X = drop constraint
*------------
*/
List *typeName; /* domain to work on */
char *name; /* column or constraint name to act on */
2002-12-06 06:00:34 +01:00
Node *def; /* definition of default or constraint */
DropBehavior behavior; /* RESTRICT or CASCADE for DROP cases */
bool missing_ok; /* skip error if missing? */
} AlterDomainStmt;
2002-12-06 06:00:34 +01:00
/* ----------------------
* Grant|Revoke Statement
* ----------------------
*/
typedef enum GrantTargetType
{
ACL_TARGET_OBJECT, /* grant on specific named object(s) */
ACL_TARGET_ALL_IN_SCHEMA, /* grant on all objects in given schema(s) */
ACL_TARGET_DEFAULTS /* ALTER DEFAULT PRIVILEGES */
} GrantTargetType;
typedef enum GrantObjectType
{
ACL_OBJECT_COLUMN, /* column */
ACL_OBJECT_RELATION, /* table, view */
ACL_OBJECT_SEQUENCE, /* sequence */
ACL_OBJECT_DATABASE, /* database */
ACL_OBJECT_DOMAIN, /* domain */
ACL_OBJECT_FDW, /* foreign-data wrapper */
ACL_OBJECT_FOREIGN_SERVER, /* foreign server */
ACL_OBJECT_FUNCTION, /* function */
ACL_OBJECT_LANGUAGE, /* procedural language */
ACL_OBJECT_LARGEOBJECT, /* largeobject */
ACL_OBJECT_NAMESPACE, /* namespace */
ACL_OBJECT_TABLESPACE, /* tablespace */
ACL_OBJECT_TYPE /* type */
} GrantObjectType;
typedef struct GrantStmt
{
NodeTag type;
bool is_grant; /* true = GRANT, false = REVOKE */
GrantTargetType targtype; /* type of the grant target */
GrantObjectType objtype; /* kind of object being operated on */
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List *objects; /* list of RangeVar nodes, FuncWithArgs nodes,
* or plain names (as Value strings) */
List *privileges; /* list of AccessPriv nodes */
/* privileges == NIL denotes ALL PRIVILEGES */
List *grantees; /* list of PrivGrantee nodes */
bool grant_option; /* grant or revoke grant option */
DropBehavior behavior; /* drop behavior (for REVOKE) */
} GrantStmt;
typedef struct PrivGrantee
{
NodeTag type;
char *rolname; /* if NULL then PUBLIC */
} PrivGrantee;
/*
* Note: FuncWithArgs carries only the types of the input parameters of the
* function. So it is sufficient to identify an existing function, but it
* is not enough info to define a function nor to call it.
*/
typedef struct FuncWithArgs
{
NodeTag type;
List *funcname; /* qualified name of function */
List *funcargs; /* list of Typename nodes */
} FuncWithArgs;
/*
* An access privilege, with optional list of column names
* priv_name == NULL denotes ALL PRIVILEGES (only used with a column list)
* cols == NIL denotes "all columns"
* Note that simple "ALL PRIVILEGES" is represented as a NIL list, not
* an AccessPriv with both fields null.
*/
typedef struct AccessPriv
{
NodeTag type;
char *priv_name; /* string name of privilege */
List *cols; /* list of Value strings */
} AccessPriv;
/* ----------------------
* Grant/Revoke Role Statement
*
* Note: because of the parsing ambiguity with the GRANT <privileges>
* statement, granted_roles is a list of AccessPriv; the execution code
* should complain if any column lists appear. grantee_roles is a list
* of role names, as Value strings.
* ----------------------
*/
typedef struct GrantRoleStmt
{
NodeTag type;
List *granted_roles; /* list of roles to be granted/revoked */
List *grantee_roles; /* list of member roles to add/delete */
bool is_grant; /* true = GRANT, false = REVOKE */
bool admin_opt; /* with admin option */
char *grantor; /* set grantor to other than current role */
DropBehavior behavior; /* drop behavior (for REVOKE) */
} GrantRoleStmt;
/* ----------------------
* Alter Default Privileges Statement
* ----------------------
*/
typedef struct AlterDefaultPrivilegesStmt
{
NodeTag type;
List *options; /* list of DefElem */
GrantStmt *action; /* GRANT/REVOKE action (with objects=NIL) */
} AlterDefaultPrivilegesStmt;
/* ----------------------
* Copy Statement
*
* We support "COPY relation FROM file", "COPY relation TO file", and
* "COPY (query) TO file". In any given CopyStmt, exactly one of "relation"
* and "query" must be non-NULL.
* ----------------------
*/
typedef struct CopyStmt
{
NodeTag type;
RangeVar *relation; /* the relation to copy */
Node *query; /* the SELECT query to copy */
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List *attlist; /* List of column names (as Strings), or NIL
* for all columns */
bool is_from; /* TO or FROM */
bool is_program; /* is 'filename' a program to popen? */
char *filename; /* filename, or NULL for STDIN/STDOUT */
List *options; /* List of DefElem nodes */
} CopyStmt;
/* ----------------------
* SET Statement (includes RESET)
*
* "SET var TO DEFAULT" and "RESET var" are semantically equivalent, but we
* preserve the distinction in VariableSetKind for CreateCommandTag().
* ----------------------
*/
typedef enum
{
VAR_SET_VALUE, /* SET var = value */
VAR_SET_DEFAULT, /* SET var TO DEFAULT */
VAR_SET_CURRENT, /* SET var FROM CURRENT */
VAR_SET_MULTI, /* special case for SET TRANSACTION ... */
VAR_RESET, /* RESET var */
VAR_RESET_ALL /* RESET ALL */
} VariableSetKind;
typedef struct VariableSetStmt
{
NodeTag type;
VariableSetKind kind;
char *name; /* variable to be set */
List *args; /* List of A_Const nodes */
bool is_local; /* SET LOCAL? */
} VariableSetStmt;
/* ----------------------
* Show Statement
* ----------------------
*/
typedef struct VariableShowStmt
{
NodeTag type;
char *name;
} VariableShowStmt;
/* ----------------------
* Create Table Statement
*
* NOTE: in the raw gram.y output, ColumnDef and Constraint nodes are
* intermixed in tableElts, and constraints is NIL. After parse analysis,
* tableElts contains just ColumnDefs, and constraints contains just
* Constraint nodes (in fact, only CONSTR_CHECK nodes, in the present
* implementation).
* ----------------------
*/
typedef struct CreateStmt
{
NodeTag type;
RangeVar *relation; /* relation to create */
List *tableElts; /* column definitions (list of ColumnDef) */
2003-08-04 02:43:34 +02:00
List *inhRelations; /* relations to inherit from (list of
* inhRelation) */
TypeName *ofTypename; /* OF typename */
List *constraints; /* constraints (list of Constraint nodes) */
List *options; /* options from WITH clause */
OnCommitAction oncommit; /* what do we do at COMMIT? */
2004-08-29 07:07:03 +02:00
char *tablespacename; /* table space to use, or NULL */
bool if_not_exists; /* just do nothing if it already exists? */
} CreateStmt;
/* ----------
* Definitions for constraints in CreateStmt
*
* Note that column defaults are treated as a type of constraint,
* even though that's a bit odd semantically.
*
* For constraints that use expressions (CONSTR_CHECK, CONSTR_DEFAULT)
* we may have the expression in either "raw" form (an untransformed
* parse tree) or "cooked" form (the nodeToString representation of
* an executable expression tree), depending on how this Constraint
* node was created (by parsing, or by inheritance from an existing
* relation). We should never have both in the same node!
*
* FKCONSTR_ACTION_xxx values are stored into pg_constraint.confupdtype
* and pg_constraint.confdeltype columns; FKCONSTR_MATCH_xxx values are
* stored into pg_constraint.confmatchtype. Changing the code values may
* require an initdb!
*
* If skip_validation is true then we skip checking that the existing rows
* in the table satisfy the constraint, and just install the catalog entries
* for the constraint. A new FK constraint is marked as valid iff
* initially_valid is true. (Usually skip_validation and initially_valid
* are inverses, but we can set both true if the table is known empty.)
*
* Constraint attributes (DEFERRABLE etc) are initially represented as
* separate Constraint nodes for simplicity of parsing. parse_utilcmd.c makes
* a pass through the constraints list to insert the info into the appropriate
* Constraint node.
* ----------
*/
typedef enum ConstrType /* types of constraints */
{
CONSTR_NULL, /* not standard SQL, but a lot of people
* expect it */
CONSTR_NOTNULL,
CONSTR_DEFAULT,
CONSTR_CHECK,
CONSTR_PRIMARY,
CONSTR_UNIQUE,
CONSTR_EXCLUSION,
CONSTR_FOREIGN,
CONSTR_ATTR_DEFERRABLE, /* attributes for previous constraint node */
CONSTR_ATTR_NOT_DEFERRABLE,
CONSTR_ATTR_DEFERRED,
CONSTR_ATTR_IMMEDIATE
} ConstrType;
/* Foreign key action codes */
#define FKCONSTR_ACTION_NOACTION 'a'
#define FKCONSTR_ACTION_RESTRICT 'r'
#define FKCONSTR_ACTION_CASCADE 'c'
#define FKCONSTR_ACTION_SETNULL 'n'
#define FKCONSTR_ACTION_SETDEFAULT 'd'
/* Foreign key matchtype codes */
#define FKCONSTR_MATCH_FULL 'f'
#define FKCONSTR_MATCH_PARTIAL 'p'
#define FKCONSTR_MATCH_SIMPLE 's'
typedef struct Constraint
{
NodeTag type;
ConstrType contype; /* see above */
/* Fields used for most/all constraint types: */
char *conname; /* Constraint name, or NULL if unnamed */
bool deferrable; /* DEFERRABLE? */
bool initdeferred; /* INITIALLY DEFERRED? */
int location; /* token location, or -1 if unknown */
/* Fields used for constraints with expressions (CHECK and DEFAULT): */
bool is_no_inherit; /* is constraint non-inheritable? */
Node *raw_expr; /* expr, as untransformed parse tree */
char *cooked_expr; /* expr, as nodeToString representation */
/* Fields used for unique constraints (UNIQUE and PRIMARY KEY): */
List *keys; /* String nodes naming referenced column(s) */
/* Fields used for EXCLUSION constraints: */
List *exclusions; /* list of (IndexElem, operator name) pairs */
/* Fields used for index constraints (UNIQUE, PRIMARY KEY, EXCLUSION): */
List *options; /* options from WITH clause */
char *indexname; /* existing index to use; otherwise NULL */
char *indexspace; /* index tablespace; NULL for default */
/* These could be, but currently are not, used for UNIQUE/PKEY: */
char *access_method; /* index access method; NULL for default */
Node *where_clause; /* partial index predicate */
/* Fields used for FOREIGN KEY constraints: */
RangeVar *pktable; /* Primary key table */
List *fk_attrs; /* Attributes of foreign key */
List *pk_attrs; /* Corresponding attrs in PK table */
char fk_matchtype; /* FULL, PARTIAL, SIMPLE */
char fk_upd_action; /* ON UPDATE action */
char fk_del_action; /* ON DELETE action */
List *old_conpfeqop; /* pg_constraint.conpfeqop of my former self */
Oid old_pktable_oid; /* pg_constraint.confrelid of my former self */
/* Fields used for constraints that allow a NOT VALID specification */
2002-09-04 22:31:48 +02:00
bool skip_validation; /* skip validation of existing rows? */
bool initially_valid; /* mark the new constraint as valid? */
} Constraint;
/* ----------------------
2004-08-29 07:07:03 +02:00
* Create/Drop Table Space Statements
* ----------------------
*/
typedef struct CreateTableSpaceStmt
{
NodeTag type;
char *tablespacename;
char *owner;
char *location;
List *options;
} CreateTableSpaceStmt;
typedef struct DropTableSpaceStmt
{
NodeTag type;
char *tablespacename;
bool missing_ok; /* skip error if missing? */
} DropTableSpaceStmt;
typedef struct AlterTableSpaceOptionsStmt
{
NodeTag type;
char *tablespacename;
List *options;
bool isReset;
} AlterTableSpaceOptionsStmt;
typedef struct AlterTableMoveAllStmt
{
NodeTag type;
char *orig_tablespacename;
ObjectType objtype; /* Object type to move */
List *roles; /* List of roles to move objects of */
char *new_tablespacename;
bool nowait;
} AlterTableMoveAllStmt;
/* ----------------------
* Create/Alter Extension Statements
* ----------------------
*/
typedef struct CreateExtensionStmt
{
NodeTag type;
char *extname;
bool if_not_exists; /* just do nothing if it already exists? */
List *options; /* List of DefElem nodes */
} CreateExtensionStmt;
/* Only used for ALTER EXTENSION UPDATE; later might need an action field */
typedef struct AlterExtensionStmt
{
NodeTag type;
char *extname;
List *options; /* List of DefElem nodes */
} AlterExtensionStmt;
typedef struct AlterExtensionContentsStmt
{
NodeTag type;
char *extname; /* Extension's name */
int action; /* +1 = add object, -1 = drop object */
ObjectType objtype; /* Object's type */
List *objname; /* Qualified name of the object */
List *objargs; /* Arguments if needed (eg, for functions) */
} AlterExtensionContentsStmt;
/* ----------------------
* Create/Alter FOREIGN DATA WRAPPER Statements
* ----------------------
*/
typedef struct CreateFdwStmt
{
NodeTag type;
char *fdwname; /* foreign-data wrapper name */
List *func_options; /* HANDLER/VALIDATOR options */
List *options; /* generic options to FDW */
} CreateFdwStmt;
typedef struct AlterFdwStmt
{
NodeTag type;
char *fdwname; /* foreign-data wrapper name */
List *func_options; /* HANDLER/VALIDATOR options */
List *options; /* generic options to FDW */
} AlterFdwStmt;
/* ----------------------
* Create/Alter FOREIGN SERVER Statements
* ----------------------
*/
typedef struct CreateForeignServerStmt
{
NodeTag type;
char *servername; /* server name */
char *servertype; /* optional server type */
char *version; /* optional server version */
char *fdwname; /* FDW name */
List *options; /* generic options to server */
} CreateForeignServerStmt;
typedef struct AlterForeignServerStmt
{
NodeTag type;
char *servername; /* server name */
char *version; /* optional server version */
List *options; /* generic options to server */
bool has_version; /* version specified */
} AlterForeignServerStmt;
/* ----------------------
* Create FOREIGN TABLE Statement
* ----------------------
*/
typedef struct CreateForeignTableStmt
{
CreateStmt base;
char *servername;
List *options;
} CreateForeignTableStmt;
/* ----------------------
* Create/Drop USER MAPPING Statements
* ----------------------
*/
typedef struct CreateUserMappingStmt
{
NodeTag type;
char *username; /* username or PUBLIC/CURRENT_USER */
char *servername; /* server name */
List *options; /* generic options to server */
} CreateUserMappingStmt;
typedef struct AlterUserMappingStmt
{
NodeTag type;
char *username; /* username or PUBLIC/CURRENT_USER */
char *servername; /* server name */
List *options; /* generic options to server */
} AlterUserMappingStmt;
typedef struct DropUserMappingStmt
{
NodeTag type;
char *username; /* username or PUBLIC/CURRENT_USER */
char *servername; /* server name */
bool missing_ok; /* ignore missing mappings */
} DropUserMappingStmt;
/* ----------------------
* Import Foreign Schema Statement
* ----------------------
*/
typedef enum ImportForeignSchemaType
{
FDW_IMPORT_SCHEMA_ALL, /* all relations wanted */
FDW_IMPORT_SCHEMA_LIMIT_TO, /* include only listed tables in import */
FDW_IMPORT_SCHEMA_EXCEPT /* exclude listed tables from import */
} ImportForeignSchemaType;
typedef struct ImportForeignSchemaStmt
{
NodeTag type;
char *server_name; /* FDW server name */
char *remote_schema; /* remote schema name to query */
char *local_schema; /* local schema to create objects in */
ImportForeignSchemaType list_type; /* type of table list */
List *table_list; /* List of RangeVar */
List *options; /* list of options to pass to FDW */
} ImportForeignSchemaStmt;
Row-Level Security Policies (RLS) Building on the updatable security-barrier views work, add the ability to define policies on tables to limit the set of rows which are returned from a query and which are allowed to be added to a table. Expressions defined by the policy for filtering are added to the security barrier quals of the query, while expressions defined to check records being added to a table are added to the with-check options of the query. New top-level commands are CREATE/ALTER/DROP POLICY and are controlled by the table owner. Row Security is able to be enabled and disabled by the owner on a per-table basis using ALTER TABLE .. ENABLE/DISABLE ROW SECURITY. Per discussion, ROW SECURITY is disabled on tables by default and must be enabled for policies on the table to be used. If no policies exist on a table with ROW SECURITY enabled, a default-deny policy is used and no records will be visible. By default, row security is applied at all times except for the table owner and the superuser. A new GUC, row_security, is added which can be set to ON, OFF, or FORCE. When set to FORCE, row security will be applied even for the table owner and superusers. When set to OFF, row security will be disabled when allowed and an error will be thrown if the user does not have rights to bypass row security. Per discussion, pg_dump sets row_security = OFF by default to ensure that exports and backups will have all data in the table or will error if there are insufficient privileges to bypass row security. A new option has been added to pg_dump, --enable-row-security, to ask pg_dump to export with row security enabled. A new role capability, BYPASSRLS, which can only be set by the superuser, is added to allow other users to be able to bypass row security using row_security = OFF. Many thanks to the various individuals who have helped with the design, particularly Robert Haas for his feedback. Authors include Craig Ringer, KaiGai Kohei, Adam Brightwell, Dean Rasheed, with additional changes and rework by me. Reviewers have included all of the above, Greg Smith, Jeff McCormick, and Robert Haas.
2014-09-19 17:18:35 +02:00
/*----------------------
* Create POLICY Statement
*----------------------
*/
typedef struct CreatePolicyStmt
{
NodeTag type;
char *policy_name; /* Policy's name */
RangeVar *table; /* the table name the policy applies to */
char *cmd; /* the command name the policy applies to */
List *roles; /* the roles associated with the policy */
Node *qual; /* the policy's condition */
Node *with_check; /* the policy's WITH CHECK condition. */
} CreatePolicyStmt;
/*----------------------
* Alter POLICY Statement
*----------------------
*/
typedef struct AlterPolicyStmt
{
NodeTag type;
char *policy_name; /* Policy's name */
RangeVar *table; /* the table name the policy applies to */
List *roles; /* the roles associated with the policy */
Node *qual; /* the policy's condition */
Node *with_check; /* the policy's WITH CHECK condition. */
} AlterPolicyStmt;
/* ----------------------
* Create TRIGGER Statement
* ----------------------
*/
typedef struct CreateTrigStmt
{
NodeTag type;
char *trigname; /* TRIGGER's name */
RangeVar *relation; /* relation trigger is on */
List *funcname; /* qual. name of function to call */
List *args; /* list of (T_String) Values or NIL */
bool row; /* ROW/STATEMENT */
/* timing uses the TRIGGER_TYPE bits defined in catalog/pg_trigger.h */
int16 timing; /* BEFORE, AFTER, or INSTEAD */
/* events uses the TRIGGER_TYPE bits defined in catalog/pg_trigger.h */
int16 events; /* "OR" of INSERT/UPDATE/DELETE/TRUNCATE */
List *columns; /* column names, or NIL for all columns */
Node *whenClause; /* qual expression, or NULL if none */
bool isconstraint; /* This is a constraint trigger */
/* The remaining fields are only used for constraint triggers */
bool deferrable; /* [NOT] DEFERRABLE */
bool initdeferred; /* INITIALLY {DEFERRED|IMMEDIATE} */
RangeVar *constrrel; /* opposite relation, if RI trigger */
} CreateTrigStmt;
/* ----------------------
* Create EVENT TRIGGER Statement
* ----------------------
*/
typedef struct CreateEventTrigStmt
{
NodeTag type;
char *trigname; /* TRIGGER's name */
char *eventname; /* event's identifier */
List *whenclause; /* list of DefElems indicating filtering */
List *funcname; /* qual. name of function to call */
} CreateEventTrigStmt;
/* ----------------------
* Alter EVENT TRIGGER Statement
* ----------------------
*/
typedef struct AlterEventTrigStmt
{
NodeTag type;
char *trigname; /* TRIGGER's name */
char tgenabled; /* trigger's firing configuration WRT
* session_replication_role */
} AlterEventTrigStmt;
/* ----------------------
* Create/Drop PROCEDURAL LANGUAGE Statements
* Create PROCEDURAL LANGUAGE Statements
* ----------------------
*/
typedef struct CreatePLangStmt
{
NodeTag type;
bool replace; /* T => replace if already exists */
char *plname; /* PL name */
List *plhandler; /* PL call handler function (qual. name) */
List *plinline; /* optional inline function (qual. name) */
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List *plvalidator; /* optional validator function (qual. name) */
bool pltrusted; /* PL is trusted */
} CreatePLangStmt;
/* ----------------------
* Create/Alter/Drop Role Statements
*
* Note: these node types are also used for the backwards-compatible
* Create/Alter/Drop User/Group statements. In the ALTER and DROP cases
* there's really no need to distinguish what the original spelling was,
* but for CREATE we mark the type because the defaults vary.
* ----------------------
*/
typedef enum RoleStmtType
{
ROLESTMT_ROLE,
ROLESTMT_USER,
ROLESTMT_GROUP
} RoleStmtType;
typedef struct CreateRoleStmt
{
NodeTag type;
RoleStmtType stmt_type; /* ROLE/USER/GROUP */
char *role; /* role name */
List *options; /* List of DefElem nodes */
} CreateRoleStmt;
typedef struct AlterRoleStmt
{
NodeTag type;
char *role; /* role name */
List *options; /* List of DefElem nodes */
int action; /* +1 = add members, -1 = drop members */
} AlterRoleStmt;
typedef struct AlterRoleSetStmt
{
NodeTag type;
char *role; /* role name */
char *database; /* database name, or NULL */
VariableSetStmt *setstmt; /* SET or RESET subcommand */
} AlterRoleSetStmt;
typedef struct DropRoleStmt
{
NodeTag type;
List *roles; /* List of roles to remove */
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bool missing_ok; /* skip error if a role is missing? */
} DropRoleStmt;
/* ----------------------
* {Create|Alter} SEQUENCE Statement
* ----------------------
*/
typedef struct CreateSeqStmt
{
NodeTag type;
RangeVar *sequence; /* the sequence to create */
List *options;
Oid ownerId; /* ID of owner, or InvalidOid for default */
bool if_not_exists; /* just do nothing if it already exists? */
} CreateSeqStmt;
typedef struct AlterSeqStmt
{
NodeTag type;
RangeVar *sequence; /* the sequence to alter */
List *options;
bool missing_ok; /* skip error if a role is missing? */
} AlterSeqStmt;
/* ----------------------
* Create {Aggregate|Operator|Type} Statement
* ----------------------
*/
typedef struct DefineStmt
{
NodeTag type;
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ObjectType kind; /* aggregate, operator, type */
bool oldstyle; /* hack to signal old CREATE AGG syntax */
List *defnames; /* qualified name (list of Value strings) */
List *args; /* a list of TypeName (if needed) */
List *definition; /* a list of DefElem */
} DefineStmt;
2002-03-20 20:45:13 +01:00
/* ----------------------
* Create Domain Statement
* ----------------------
*/
typedef struct CreateDomainStmt
{
NodeTag type;
List *domainname; /* qualified name (list of Value strings) */
TypeName *typeName; /* the base type */
Remove collation information from TypeName, where it does not belong. The initial collations patch treated a COLLATE spec as part of a TypeName, following what can only be described as brain fade on the part of the SQL committee. It's a lot more reasonable to treat COLLATE as a syntactically separate object, so that it can be added in only the productions where it actually belongs, rather than needing to reject it in a boatload of places where it doesn't belong (something the original patch mostly failed to do). In addition this change lets us meet the spec's requirement to allow COLLATE anywhere in the clauses of a ColumnDef, and it avoids unfriendly behavior for constructs such as "foo::type COLLATE collation". To do this, pull collation information out of TypeName and put it in ColumnDef instead, thus reverting most of the collation-related changes in parse_type.c's API. I made one additional structural change, which was to use a ColumnDef as an intermediate node in AT_AlterColumnType AlterTableCmd nodes. This provides enough room to get rid of the "transform" wart in AlterTableCmd too, since the ColumnDef can carry the USING expression easily enough. Also fix some other minor bugs that have crept in in the same areas, like failure to copy recently-added fields of ColumnDef in copyfuncs.c. While at it, document the formerly secret ability to specify a collation in ALTER TABLE ALTER COLUMN TYPE, ALTER TYPE ADD ATTRIBUTE, and ALTER TYPE ALTER ATTRIBUTE TYPE; and correct some misstatements about what the default collation selection will be when COLLATE is omitted. BTW, the three-parameter form of format_type() should go away too, since it just contributes to the confusion in this area; but I'll do that in a separate patch.
2011-03-10 04:38:52 +01:00
CollateClause *collClause; /* untransformed COLLATE spec, if any */
List *constraints; /* constraints (list of Constraint nodes) */
2002-03-20 20:45:13 +01:00
} CreateDomainStmt;
/* ----------------------
* Create Operator Class Statement
* ----------------------
*/
typedef struct CreateOpClassStmt
{
NodeTag type;
List *opclassname; /* qualified name (list of Value strings) */
List *opfamilyname; /* qualified name (ditto); NIL if omitted */
char *amname; /* name of index AM opclass is for */
TypeName *datatype; /* datatype of indexed column */
List *items; /* List of CreateOpClassItem nodes */
bool isDefault; /* Should be marked as default for type? */
} CreateOpClassStmt;
#define OPCLASS_ITEM_OPERATOR 1
#define OPCLASS_ITEM_FUNCTION 2
#define OPCLASS_ITEM_STORAGETYPE 3
typedef struct CreateOpClassItem
{
NodeTag type;
int itemtype; /* see codes above */
/* fields used for an operator or function item: */
List *name; /* operator or function name */
List *args; /* argument types */
int number; /* strategy num or support proc num */
List *order_family; /* only used for ordering operators */
List *class_args; /* only used for functions */
/* fields used for a storagetype item: */
TypeName *storedtype; /* datatype stored in index */
} CreateOpClassItem;
/* ----------------------
* Create Operator Family Statement
* ----------------------
*/
typedef struct CreateOpFamilyStmt
{
NodeTag type;
List *opfamilyname; /* qualified name (list of Value strings) */
char *amname; /* name of index AM opfamily is for */
} CreateOpFamilyStmt;
/* ----------------------
* Alter Operator Family Statement
* ----------------------
*/
typedef struct AlterOpFamilyStmt
{
NodeTag type;
List *opfamilyname; /* qualified name (list of Value strings) */
char *amname; /* name of index AM opfamily is for */
bool isDrop; /* ADD or DROP the items? */
List *items; /* List of CreateOpClassItem nodes */
} AlterOpFamilyStmt;
2000-02-18 10:30:20 +01:00
/* ----------------------
* Drop Table|Sequence|View|Index|Type|Domain|Conversion|Schema Statement
2000-02-18 10:30:20 +01:00
* ----------------------
*/
typedef struct DropStmt
{
NodeTag type;
List *objects; /* list of sublists of names (as Values) */
List *arguments; /* list of sublists of arguments (as Values) */
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ObjectType removeType; /* object type */
DropBehavior behavior; /* RESTRICT or CASCADE behavior */
bool missing_ok; /* skip error if object is missing? */
bool concurrent; /* drop index concurrently? */
} DropStmt;
/* ----------------------
* Truncate Table Statement
* ----------------------
*/
typedef struct TruncateStmt
{
NodeTag type;
List *relations; /* relations (RangeVars) to be truncated */
bool restart_seqs; /* restart owned sequences? */
DropBehavior behavior; /* RESTRICT or CASCADE behavior */
} TruncateStmt;
/* ----------------------
* Comment On Statement
* ----------------------
*/
typedef struct CommentStmt
{
NodeTag type;
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ObjectType objtype; /* Object's type */
List *objname; /* Qualified name of the object */
List *objargs; /* Arguments if needed (eg, for functions) */
char *comment; /* Comment to insert, or NULL to remove */
} CommentStmt;
/* ----------------------
* SECURITY LABEL Statement
* ----------------------
*/
typedef struct SecLabelStmt
{
NodeTag type;
ObjectType objtype; /* Object's type */
List *objname; /* Qualified name of the object */
List *objargs; /* Arguments if needed (eg, for functions) */
char *provider; /* Label provider (or NULL) */
char *label; /* New security label to be assigned */
} SecLabelStmt;
/* ----------------------
* Declare Cursor Statement
*
* Note: the "query" field of DeclareCursorStmt is only used in the raw grammar
* output. After parse analysis it's set to null, and the Query points to the
* DeclareCursorStmt, not vice versa.
* ----------------------
*/
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#define CURSOR_OPT_BINARY 0x0001 /* BINARY */
#define CURSOR_OPT_SCROLL 0x0002 /* SCROLL explicitly given */
#define CURSOR_OPT_NO_SCROLL 0x0004 /* NO SCROLL explicitly given */
#define CURSOR_OPT_INSENSITIVE 0x0008 /* INSENSITIVE */
#define CURSOR_OPT_HOLD 0x0010 /* WITH HOLD */
/* these planner-control flags do not correspond to any SQL grammar: */
2007-11-15 22:14:46 +01:00
#define CURSOR_OPT_FAST_PLAN 0x0020 /* prefer fast-start plan */
#define CURSOR_OPT_GENERIC_PLAN 0x0040 /* force use of generic plan */
#define CURSOR_OPT_CUSTOM_PLAN 0x0080 /* force use of custom plan */
typedef struct DeclareCursorStmt
{
NodeTag type;
char *portalname; /* name of the portal (cursor) */
int options; /* bitmask of options (see above) */
Node *query; /* the raw SELECT query */
} DeclareCursorStmt;
/* ----------------------
* Close Portal Statement
* ----------------------
*/
typedef struct ClosePortalStmt
{
NodeTag type;
char *portalname; /* name of the portal (cursor) */
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/* NULL means CLOSE ALL */
} ClosePortalStmt;
/* ----------------------
* Fetch Statement (also Move)
* ----------------------
*/
typedef enum FetchDirection
{
/* for these, howMany is how many rows to fetch; FETCH_ALL means ALL */
FETCH_FORWARD,
FETCH_BACKWARD,
/* for these, howMany indicates a position; only one row is fetched */
FETCH_ABSOLUTE,
FETCH_RELATIVE
} FetchDirection;
#define FETCH_ALL LONG_MAX
typedef struct FetchStmt
{
NodeTag type;
FetchDirection direction; /* see above */
long howMany; /* number of rows, or position argument */
char *portalname; /* name of portal (cursor) */
bool ismove; /* TRUE if MOVE */
} FetchStmt;
/* ----------------------
* Create Index Statement
*
* This represents creation of an index and/or an associated constraint.
* If isconstraint is true, we should create a pg_constraint entry along
* with the index. But if indexOid isn't InvalidOid, we are not creating an
* index, just a UNIQUE/PKEY constraint using an existing index. isconstraint
* must always be true in this case, and the fields describing the index
* properties are empty.
* ----------------------
*/
typedef struct IndexStmt
{
NodeTag type;
char *idxname; /* name of new index, or NULL for default */
RangeVar *relation; /* relation to build index on */
char *accessMethod; /* name of access method (eg. btree) */
char *tableSpace; /* tablespace, or NULL for default */
List *indexParams; /* columns to index: a list of IndexElem */
List *options; /* WITH clause options: a list of DefElem */
Node *whereClause; /* qualification (partial-index predicate) */
2010-02-26 03:01:40 +01:00
List *excludeOpNames; /* exclusion operator names, or NIL if none */
char *idxcomment; /* comment to apply to index, or NULL */
Oid indexOid; /* OID of an existing index, if any */
Oid oldNode; /* relfilenode of existing storage, if any */
bool unique; /* is index unique? */
bool primary; /* is index a primary key? */
bool isconstraint; /* is it for a pkey/unique constraint? */
bool deferrable; /* is the constraint DEFERRABLE? */
bool initdeferred; /* is the constraint INITIALLY DEFERRED? */
Get rid of multiple applications of transformExpr() to the same tree. transformExpr() has for many years had provisions to do nothing when applied to an already-transformed expression tree. However, this was always ugly and of dubious reliability, so we'd be much better off without it. The primary historical reason for it was that gram.y sometimes returned multiple links to the same subexpression, which is no longer true as of my BETWEEN fixes. We'd also grown some lazy hacks in CREATE TABLE LIKE (failing to distinguish between raw and already-transformed index specifications) and one or two other places. This patch removes the need for and support for re-transforming already transformed expressions. The index case is dealt with by adding a flag to struct IndexStmt to indicate that it's already been transformed; which has some benefit anyway in that tablecmds.c can now Assert that transformation has happened rather than just assuming. The other main reason was some rather sloppy code for array type coercion, which can be fixed (and its performance improved too) by refactoring. I did leave transformJoinUsingClause() still constructing expressions containing untransformed operator nodes being applied to Vars, so that transformExpr() still has to allow Var inputs. But that's a much narrower, and safer, special case than before, since Vars will never appear in a raw parse tree, and they don't have any substructure to worry about. In passing fix some oversights in the patch that added CREATE INDEX IF NOT EXISTS (missing processing of IndexStmt.if_not_exists). These appear relatively harmless, but still sloppy coding practice.
2015-02-22 19:59:09 +01:00
bool transformed; /* true when transformIndexStmt is finished */
bool concurrent; /* should this be a concurrent index build? */
bool if_not_exists; /* just do nothing if index already exists? */
} IndexStmt;
/* ----------------------
* Create Function Statement
* ----------------------
*/
typedef struct CreateFunctionStmt
{
NodeTag type;
bool replace; /* T => replace if already exists */
List *funcname; /* qualified name of function to create */
List *parameters; /* a list of FunctionParameter */
TypeName *returnType; /* the return type */
List *options; /* a list of DefElem */
List *withClause; /* a list of DefElem */
} CreateFunctionStmt;
typedef enum FunctionParameterMode
{
/* the assigned enum values appear in pg_proc, don't change 'em! */
FUNC_PARAM_IN = 'i', /* input only */
FUNC_PARAM_OUT = 'o', /* output only */
FUNC_PARAM_INOUT = 'b', /* both */
FUNC_PARAM_VARIADIC = 'v', /* variadic (always input) */
FUNC_PARAM_TABLE = 't' /* table function output column */
} FunctionParameterMode;
typedef struct FunctionParameter
{
NodeTag type;
char *name; /* parameter name, or NULL if not given */
TypeName *argType; /* TypeName for parameter type */
FunctionParameterMode mode; /* IN/OUT/etc */
Node *defexpr; /* raw default expr, or NULL if not given */
} FunctionParameter;
typedef struct AlterFunctionStmt
{
NodeTag type;
FuncWithArgs *func; /* name and args of function */
List *actions; /* list of DefElem */
} AlterFunctionStmt;
/* ----------------------
* DO Statement
*
* DoStmt is the raw parser output, InlineCodeBlock is the execution-time API
* ----------------------
*/
typedef struct DoStmt
{
NodeTag type;
List *args; /* List of DefElem nodes */
} DoStmt;
typedef struct InlineCodeBlock
{
NodeTag type;
char *source_text; /* source text of anonymous code block */
Oid langOid; /* OID of selected language */
2010-02-26 03:01:40 +01:00
bool langIsTrusted; /* trusted property of the language */
} InlineCodeBlock;
/* ----------------------
* Alter Object Rename Statement
* ----------------------
*/
typedef struct RenameStmt
{
NodeTag type;
ObjectType renameType; /* OBJECT_TABLE, OBJECT_COLUMN, etc */
ObjectType relationType; /* if column name, associated relation type */
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RangeVar *relation; /* in case it's a table */
List *object; /* in case it's some other object */
List *objarg; /* argument types, if applicable */
2003-08-04 02:43:34 +02:00
char *subname; /* name of contained object (column, rule,
* trigger, etc) */
char *newname; /* the new name */
DropBehavior behavior; /* RESTRICT or CASCADE behavior */
bool missing_ok; /* skip error if missing? */
} RenameStmt;
/* ----------------------
* ALTER object SET SCHEMA Statement
* ----------------------
*/
typedef struct AlterObjectSchemaStmt
{
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NodeTag type;
ObjectType objectType; /* OBJECT_TABLE, OBJECT_TYPE, etc */
RangeVar *relation; /* in case it's a table */
List *object; /* in case it's some other object */
List *objarg; /* argument types, if applicable */
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char *newschema; /* the new schema */
bool missing_ok; /* skip error if missing? */
} AlterObjectSchemaStmt;
/* ----------------------
2004-08-29 07:07:03 +02:00
* Alter Object Owner Statement
* ----------------------
*/
typedef struct AlterOwnerStmt
{
NodeTag type;
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ObjectType objectType; /* OBJECT_TABLE, OBJECT_TYPE, etc */
RangeVar *relation; /* in case it's a table */
List *object; /* in case it's some other object */
List *objarg; /* argument types, if applicable */
char *newowner; /* the new owner */
} AlterOwnerStmt;
/* ----------------------
* Create Rule Statement
* ----------------------
*/
typedef struct RuleStmt
{
NodeTag type;
RangeVar *relation; /* relation the rule is for */
char *rulename; /* name of the rule */
Node *whereClause; /* qualifications */
CmdType event; /* SELECT, INSERT, etc */
bool instead; /* is a 'do instead'? */
List *actions; /* the action statements */
bool replace; /* OR REPLACE */
} RuleStmt;
/* ----------------------
* Notify Statement
* ----------------------
1998-12-04 16:34:49 +01:00
*/
typedef struct NotifyStmt
1998-12-04 16:34:49 +01:00
{
NodeTag type;
char *conditionname; /* condition name to notify */
char *payload; /* the payload string, or NULL if none */
} NotifyStmt;
1998-12-04 16:34:49 +01:00
/* ----------------------
* Listen Statement
* ----------------------
1998-12-04 16:34:49 +01:00
*/
typedef struct ListenStmt
1998-12-04 16:34:49 +01:00
{
NodeTag type;
char *conditionname; /* condition name to listen on */
} ListenStmt;
1998-12-04 16:34:49 +01:00
/* ----------------------
* Unlisten Statement
* ----------------------
*/
typedef struct UnlistenStmt
{
NodeTag type;
char *conditionname; /* name to unlisten on, or NULL for all */
} UnlistenStmt;
/* ----------------------
* {Begin|Commit|Rollback} Transaction Statement
* ----------------------
*/
typedef enum TransactionStmtKind
{
TRANS_STMT_BEGIN,
TRANS_STMT_START, /* semantically identical to BEGIN */
TRANS_STMT_COMMIT,
TRANS_STMT_ROLLBACK,
TRANS_STMT_SAVEPOINT,
TRANS_STMT_RELEASE,
TRANS_STMT_ROLLBACK_TO,
TRANS_STMT_PREPARE,
TRANS_STMT_COMMIT_PREPARED,
TRANS_STMT_ROLLBACK_PREPARED
} TransactionStmtKind;
typedef struct TransactionStmt
{
NodeTag type;
TransactionStmtKind kind; /* see above */
List *options; /* for BEGIN/START and savepoint commands */
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char *gid; /* for two-phase-commit related commands */
} TransactionStmt;
/* ----------------------
* Create Type Statement, composite types
* ----------------------
*/
typedef struct CompositeTypeStmt
{
NodeTag type;
RangeVar *typevar; /* the composite type to be created */
List *coldeflist; /* list of ColumnDef nodes */
} CompositeTypeStmt;
/* ----------------------
* Create Type Statement, enum types
* ----------------------
*/
typedef struct CreateEnumStmt
{
NodeTag type;
List *typeName; /* qualified name (list of Value strings) */
List *vals; /* enum values (list of Value strings) */
} CreateEnumStmt;
/* ----------------------
* Create Type Statement, range types
* ----------------------
*/
typedef struct CreateRangeStmt
{
NodeTag type;
List *typeName; /* qualified name (list of Value strings) */
List *params; /* range parameters (list of DefElem) */
} CreateRangeStmt;
/* ----------------------
* Alter Type Statement, enum types
* ----------------------
*/
typedef struct AlterEnumStmt
{
NodeTag type;
List *typeName; /* qualified name (list of Value strings) */
char *newVal; /* new enum value's name */
char *newValNeighbor; /* neighboring enum value, if specified */
bool newValIsAfter; /* place new enum value after neighbor? */
bool skipIfExists; /* no error if label already exists */
} AlterEnumStmt;
/* ----------------------
* Create View Statement
* ----------------------
*/
typedef enum ViewCheckOption
{
NO_CHECK_OPTION,
LOCAL_CHECK_OPTION,
CASCADED_CHECK_OPTION
} ViewCheckOption;
typedef struct ViewStmt
{
NodeTag type;
RangeVar *view; /* the view to be created */
List *aliases; /* target column names */
Node *query; /* the SELECT query */
bool replace; /* replace an existing view? */
List *options; /* options from WITH clause */
ViewCheckOption withCheckOption; /* WITH CHECK OPTION */
} ViewStmt;
/* ----------------------
* Load Statement
* ----------------------
*/
typedef struct LoadStmt
{
NodeTag type;
char *filename; /* file to load */
} LoadStmt;
/* ----------------------
* Createdb Statement
* ----------------------
*/
typedef struct CreatedbStmt
{
NodeTag type;
char *dbname; /* name of database to create */
List *options; /* List of DefElem nodes */
} CreatedbStmt;
/* ----------------------
* Alter Database
* ----------------------
*/
typedef struct AlterDatabaseStmt
{
NodeTag type;
char *dbname; /* name of database to alter */
List *options; /* List of DefElem nodes */
} AlterDatabaseStmt;
typedef struct AlterDatabaseSetStmt
{
NodeTag type;
char *dbname; /* database name */
VariableSetStmt *setstmt; /* SET or RESET subcommand */
} AlterDatabaseSetStmt;
/* ----------------------
* Dropdb Statement
* ----------------------
*/
typedef struct DropdbStmt
{
NodeTag type;
char *dbname; /* database to drop */
bool missing_ok; /* skip error if db is missing? */
} DropdbStmt;
/* ----------------------
* Alter System Statement
* ----------------------
*/
typedef struct AlterSystemStmt
{
NodeTag type;
VariableSetStmt *setstmt; /* SET subcommand */
} AlterSystemStmt;
/* ----------------------
* Cluster Statement (support pbrown's cluster index implementation)
* ----------------------
*/
typedef struct ClusterStmt
{
NodeTag type;
RangeVar *relation; /* relation being indexed, or NULL if all */
char *indexname; /* original index defined */
bool verbose; /* print progress info */
} ClusterStmt;
/* ----------------------
* Vacuum and Analyze Statements
*
* Even though these are nominally two statements, it's convenient to use
* just one node type for both. Note that at least one of VACOPT_VACUUM
* and VACOPT_ANALYZE must be set in options. VACOPT_FREEZE is an internal
* convenience for the grammar and is not examined at runtime --- the
* freeze_min_age and freeze_table_age fields are what matter.
* ----------------------
*/
typedef enum VacuumOption
{
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VACOPT_VACUUM = 1 << 0, /* do VACUUM */
VACOPT_ANALYZE = 1 << 1, /* do ANALYZE */
VACOPT_VERBOSE = 1 << 2, /* print progress info */
VACOPT_FREEZE = 1 << 3, /* FREEZE option */
VACOPT_FULL = 1 << 4, /* FULL (non-concurrent) vacuum */
VACOPT_NOWAIT = 1 << 5 /* don't wait to get lock (autovacuum only) */
} VacuumOption;
typedef struct VacuumStmt
{
NodeTag type;
int options; /* OR of VacuumOption flags */
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int freeze_min_age; /* min freeze age, or -1 to use default */
int freeze_table_age; /* age at which to scan whole table */
int multixact_freeze_min_age; /* min multixact freeze age,
* or -1 to use default */
int multixact_freeze_table_age; /* multixact age at which to
* scan whole table */
RangeVar *relation; /* single table to process, or NULL */
List *va_cols; /* list of column names, or NIL for all */
} VacuumStmt;
/* ----------------------
* Explain Statement
*
* The "query" field is either a raw parse tree (SelectStmt, InsertStmt, etc)
* or a Query node if parse analysis has been done. Note that rewriting and
* planning of the query are always postponed until execution of EXPLAIN.
* ----------------------
*/
typedef struct ExplainStmt
{
NodeTag type;
Node *query; /* the query (see comments above) */
List *options; /* list of DefElem nodes */
} ExplainStmt;
/* ----------------------
* CREATE TABLE AS Statement (a/k/a SELECT INTO)
*
* A query written as CREATE TABLE AS will produce this node type natively.
* A query written as SELECT ... INTO will be transformed to this form during
* parse analysis.
* A query written as CREATE MATERIALIZED view will produce this node type,
* during parse analysis, since it needs all the same data.
*
* The "query" field is handled similarly to EXPLAIN, though note that it
* can be a SELECT or an EXECUTE, but not other DML statements.
* ----------------------
*/
typedef struct CreateTableAsStmt
{
NodeTag type;
Node *query; /* the query (see comments above) */
IntoClause *into; /* destination table */
ObjectType relkind; /* OBJECT_TABLE or OBJECT_MATVIEW */
bool is_select_into; /* it was written as SELECT INTO */
bool if_not_exists; /* just do nothing if it already exists? */
} CreateTableAsStmt;
/* ----------------------
* REFRESH MATERIALIZED VIEW Statement
* ----------------------
*/
typedef struct RefreshMatViewStmt
{
NodeTag type;
bool concurrent; /* allow concurrent access? */
bool skipData; /* true for WITH NO DATA */
RangeVar *relation; /* relation to insert into */
} RefreshMatViewStmt;
/* ----------------------
* Checkpoint Statement
* ----------------------
*/
typedef struct CheckPointStmt
{
NodeTag type;
} CheckPointStmt;
/* ----------------------
* Discard Statement
* ----------------------
*/
typedef enum DiscardMode
{
DISCARD_ALL,
DISCARD_PLANS,
DISCARD_SEQUENCES,
DISCARD_TEMP
} DiscardMode;
typedef struct DiscardStmt
{
NodeTag type;
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DiscardMode target;
} DiscardStmt;
/* ----------------------
* LOCK Statement
* ----------------------
*/
typedef struct LockStmt
{
NodeTag type;
List *relations; /* relations to lock */
int mode; /* lock mode */
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bool nowait; /* no wait mode */
} LockStmt;
/* ----------------------
* SET CONSTRAINTS Statement
* ----------------------
*/
typedef struct ConstraintsSetStmt
{
NodeTag type;
List *constraints; /* List of names as RangeVars */
bool deferred;
} ConstraintsSetStmt;
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/* ----------------------
* REINDEX Statement
* ----------------------
*/
typedef enum ReindexObjectType
{
REINDEX_OBJECT_INDEX, /* index */
REINDEX_OBJECT_TABLE, /* table or materialized view */
REINDEX_OBJECT_SCHEMA, /* schema */
REINDEX_OBJECT_SYSTEM, /* system catalogs */
REINDEX_OBJECT_DATABASE /* database */
} ReindexObjectType;
typedef struct ReindexStmt
{
NodeTag type;
ReindexObjectType kind; /* REINDEX_OBJECT_INDEX, REINDEX_OBJECT_TABLE, etc. */
RangeVar *relation; /* Table or index to reindex */
const char *name; /* name of database to reindex */
} ReindexStmt;
/* ----------------------
* CREATE CONVERSION Statement
* ----------------------
*/
typedef struct CreateConversionStmt
{
NodeTag type;
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List *conversion_name; /* Name of the conversion */
char *for_encoding_name; /* source encoding name */
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char *to_encoding_name; /* destination encoding name */
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List *func_name; /* qualified conversion function name */
bool def; /* is this a default conversion? */
} CreateConversionStmt;
/* ----------------------
* CREATE CAST Statement
* ----------------------
*/
typedef struct CreateCastStmt
{
NodeTag type;
TypeName *sourcetype;
TypeName *targettype;
FuncWithArgs *func;
CoercionContext context;
bool inout;
} CreateCastStmt;
/* ----------------------
* PREPARE Statement
* ----------------------
*/
typedef struct PrepareStmt
{
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NodeTag type;
char *name; /* Name of plan, arbitrary */
List *argtypes; /* Types of parameters (List of TypeName) */
Node *query; /* The query itself (as a raw parsetree) */
} PrepareStmt;
/* ----------------------
* EXECUTE Statement
* ----------------------
*/
typedef struct ExecuteStmt
{
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NodeTag type;
char *name; /* The name of the plan to execute */
List *params; /* Values to assign to parameters */
} ExecuteStmt;
/* ----------------------
* DEALLOCATE Statement
* ----------------------
*/
typedef struct DeallocateStmt
{
NodeTag type;
char *name; /* The name of the plan to remove */
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/* NULL means DEALLOCATE ALL */
} DeallocateStmt;
/*
* DROP OWNED statement
*/
typedef struct DropOwnedStmt
{
NodeTag type;
List *roles;
DropBehavior behavior;
} DropOwnedStmt;
/*
* REASSIGN OWNED statement
*/
typedef struct ReassignOwnedStmt
{
NodeTag type;
List *roles;
char *newrole;
} ReassignOwnedStmt;
/*
* TS Dictionary stmts: DefineStmt, RenameStmt and DropStmt are default
*/
typedef struct AlterTSDictionaryStmt
{
NodeTag type;
List *dictname; /* qualified name (list of Value strings) */
List *options; /* List of DefElem nodes */
} AlterTSDictionaryStmt;
/*
* TS Configuration stmts: DefineStmt, RenameStmt and DropStmt are default
*/
typedef struct AlterTSConfigurationStmt
{
NodeTag type;
List *cfgname; /* qualified name (list of Value strings) */
/*
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* dicts will be non-NIL if ADD/ALTER MAPPING was specified. If dicts is
* NIL, but tokentype isn't, DROP MAPPING was specified.
*/
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List *tokentype; /* list of Value strings */
List *dicts; /* list of list of Value strings */
bool override; /* if true - remove old variant */
bool replace; /* if true - replace dictionary by another */
bool missing_ok; /* for DROP - skip error if missing? */
} AlterTSConfigurationStmt;
#endif /* PARSENODES_H */