postgresql/src/backend/catalog/index.c

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/*-------------------------------------------------------------------------
*
* index.c
* code to create and destroy POSTGRES index relations
*
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* Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
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* src/backend/catalog/index.c
*
*
* INTERFACE ROUTINES
* index_create() - Create a cataloged index relation
* index_drop() - Removes index relation from catalogs
* BuildIndexInfo() - Prepare to insert index tuples
* FormIndexDatum() - Construct datum vector for one index tuple
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
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#include <unistd.h>
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#include "access/genam.h"
#include "access/heapam.h"
#include "access/relscan.h"
#include "access/sysattr.h"
#include "access/transam.h"
#include "access/xact.h"
#include "bootstrap/bootstrap.h"
#include "catalog/catalog.h"
#include "catalog/dependency.h"
#include "catalog/heap.h"
#include "catalog/index.h"
#include "catalog/indexing.h"
#include "catalog/namespace.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_tablespace.h"
#include "catalog/pg_trigger.h"
#include "catalog/pg_type.h"
#include "catalog/storage.h"
#include "commands/tablecmds.h"
#include "commands/trigger.h"
#include "executor/executor.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/clauses.h"
#include "parser/parser.h"
#include "storage/bufmgr.h"
#include "storage/lmgr.h"
#include "storage/procarray.h"
#include "storage/smgr.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
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#include "utils/guc.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/relcache.h"
#include "utils/syscache.h"
#include "utils/tuplesort.h"
#include "utils/snapmgr.h"
#include "utils/tqual.h"
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/* Potentially set by contrib/pg_upgrade_support functions */
Oid binary_upgrade_next_index_pg_class_oid = InvalidOid;
/* state info for validate_index bulkdelete callback */
typedef struct
{
Tuplesortstate *tuplesort; /* for sorting the index TIDs */
/* statistics (for debug purposes only): */
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double htups,
itups,
tups_inserted;
} v_i_state;
/* non-export function prototypes */
static bool relationHasPrimaryKey(Relation rel);
static TupleDesc ConstructTupleDescriptor(Relation heapRelation,
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IndexInfo *indexInfo,
List *indexColNames,
Oid accessMethodObjectId,
Oid *collationObjectId,
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Oid *classObjectId);
static void InitializeAttributeOids(Relation indexRelation,
int numatts, Oid indexoid);
static void AppendAttributeTuples(Relation indexRelation, int numatts);
static void UpdateIndexRelation(Oid indexoid, Oid heapoid,
IndexInfo *indexInfo,
Oid *collationOids,
Oid *classOids,
int16 *coloptions,
bool primary,
bool isexclusion,
bool immediate,
bool isvalid);
static void index_update_stats(Relation rel,
bool hasindex, bool isprimary,
Oid reltoastidxid, double reltuples);
static void IndexCheckExclusion(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo);
static bool validate_index_callback(ItemPointer itemptr, void *opaque);
static void validate_index_heapscan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
Snapshot snapshot,
v_i_state *state);
static Oid IndexGetRelation(Oid indexId);
static void SetReindexProcessing(Oid heapOid, Oid indexOid);
static void ResetReindexProcessing(void);
static void SetReindexPending(List *indexes);
static void RemoveReindexPending(Oid indexOid);
static void ResetReindexPending(void);
/*
* relationHasPrimaryKey
* See whether an existing relation has a primary key.
*
* Caller must have suitable lock on the relation.
*/
static bool
relationHasPrimaryKey(Relation rel)
{
bool result = false;
List *indexoidlist;
ListCell *indexoidscan;
/*
* Get the list of index OIDs for the table from the relcache, and look up
* each one in the pg_index syscache until we find one marked primary key
* (hopefully there isn't more than one such).
*/
indexoidlist = RelationGetIndexList(rel);
foreach(indexoidscan, indexoidlist)
{
Oid indexoid = lfirst_oid(indexoidscan);
HeapTuple indexTuple;
indexTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexoid));
if (!HeapTupleIsValid(indexTuple)) /* should not happen */
elog(ERROR, "cache lookup failed for index %u", indexoid);
result = ((Form_pg_index) GETSTRUCT(indexTuple))->indisprimary;
ReleaseSysCache(indexTuple);
if (result)
break;
}
list_free(indexoidlist);
return result;
}
/*
* index_check_primary_key
* Apply special checks needed before creating a PRIMARY KEY index
*
* This processing used to be in DefineIndex(), but has been split out
* so that it can be applied during ALTER TABLE ADD PRIMARY KEY USING INDEX.
*
* We check for a pre-existing primary key, and that all columns of the index
* are simple column references (not expressions), and that all those
* columns are marked NOT NULL. If they aren't (which can only happen during
* ALTER TABLE ADD CONSTRAINT, since the parser forces such columns to be
* created NOT NULL during CREATE TABLE), do an ALTER SET NOT NULL to mark
* them so --- or fail if they are not in fact nonnull.
*
* Caller had better have at least ShareLock on the table, else the not-null
* checking isn't trustworthy.
*/
void
index_check_primary_key(Relation heapRel,
IndexInfo *indexInfo,
bool is_alter_table)
{
List *cmds;
int i;
/*
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* If ALTER TABLE, check that there isn't already a PRIMARY KEY. In CREATE
* TABLE, we have faith that the parser rejected multiple pkey clauses;
* and CREATE INDEX doesn't have a way to say PRIMARY KEY, so it's no
* problem either.
*/
if (is_alter_table &&
relationHasPrimaryKey(heapRel))
{
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
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errmsg("multiple primary keys for table \"%s\" are not allowed",
RelationGetRelationName(heapRel))));
}
/*
* Check that all of the attributes in a primary key are marked as not
* null, otherwise attempt to ALTER TABLE .. SET NOT NULL
*/
cmds = NIL;
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
AttrNumber attnum = indexInfo->ii_KeyAttrNumbers[i];
HeapTuple atttuple;
Form_pg_attribute attform;
if (attnum == 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("primary keys cannot be expressions")));
/* System attributes are never null, so no need to check */
if (attnum < 0)
continue;
atttuple = SearchSysCache2(ATTNUM,
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ObjectIdGetDatum(RelationGetRelid(heapRel)),
Int16GetDatum(attnum));
if (!HeapTupleIsValid(atttuple))
elog(ERROR, "cache lookup failed for attribute %d of relation %u",
attnum, RelationGetRelid(heapRel));
attform = (Form_pg_attribute) GETSTRUCT(atttuple);
if (!attform->attnotnull)
{
/* Add a subcommand to make this one NOT NULL */
AlterTableCmd *cmd = makeNode(AlterTableCmd);
cmd->subtype = AT_SetNotNull;
cmd->name = pstrdup(NameStr(attform->attname));
cmds = lappend(cmds, cmd);
}
ReleaseSysCache(atttuple);
}
/*
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* XXX: Shouldn't the ALTER TABLE .. SET NOT NULL cascade to child tables?
* Currently, since the PRIMARY KEY itself doesn't cascade, we don't
* cascade the notnull constraint(s) either; but this is pretty debatable.
*
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* XXX: possible future improvement: when being called from ALTER TABLE,
* it would be more efficient to merge this with the outer ALTER TABLE, so
* as to avoid two scans. But that seems to complicate DefineIndex's API
* unduly.
*/
if (cmds)
AlterTableInternal(RelationGetRelid(heapRel), cmds, false);
}
/*
* ConstructTupleDescriptor
*
* Build an index tuple descriptor for a new index
*/
static TupleDesc
ConstructTupleDescriptor(Relation heapRelation,
IndexInfo *indexInfo,
List *indexColNames,
Oid accessMethodObjectId,
Oid *collationObjectId,
Oid *classObjectId)
{
int numatts = indexInfo->ii_NumIndexAttrs;
ListCell *colnames_item = list_head(indexColNames);
ListCell *indexpr_item = list_head(indexInfo->ii_Expressions);
HeapTuple amtuple;
Form_pg_am amform;
TupleDesc heapTupDesc;
TupleDesc indexTupDesc;
int natts; /* #atts in heap rel --- for error checks */
int i;
/* We need access to the index AM's pg_am tuple */
amtuple = SearchSysCache1(AMOID,
ObjectIdGetDatum(accessMethodObjectId));
if (!HeapTupleIsValid(amtuple))
elog(ERROR, "cache lookup failed for access method %u",
accessMethodObjectId);
amform = (Form_pg_am) GETSTRUCT(amtuple);
/* ... and to the table's tuple descriptor */
heapTupDesc = RelationGetDescr(heapRelation);
natts = RelationGetForm(heapRelation)->relnatts;
/*
* allocate the new tuple descriptor
*/
indexTupDesc = CreateTemplateTupleDesc(numatts, false);
/*
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* For simple index columns, we copy the pg_attribute row from the parent
* relation and modify it as necessary. For expressions we have to cons
* up a pg_attribute row the hard way.
*/
for (i = 0; i < numatts; i++)
{
AttrNumber atnum = indexInfo->ii_KeyAttrNumbers[i];
Form_pg_attribute to = indexTupDesc->attrs[i];
HeapTuple tuple;
Form_pg_type typeTup;
Form_pg_opclass opclassTup;
Oid keyType;
if (atnum != 0)
{
/* Simple index column */
Form_pg_attribute from;
if (atnum < 0)
{
/*
* here we are indexing on a system attribute (-1...-n)
*/
from = SystemAttributeDefinition(atnum,
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heapRelation->rd_rel->relhasoids);
}
else
{
/*
* here we are indexing on a normal attribute (1...n)
*/
if (atnum > natts) /* safety check */
elog(ERROR, "invalid column number %d", atnum);
from = heapTupDesc->attrs[AttrNumberGetAttrOffset(atnum)];
}
/*
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* now that we've determined the "from", let's copy the tuple desc
* data...
*/
memcpy(to, from, ATTRIBUTE_FIXED_PART_SIZE);
/*
* Fix the stuff that should not be the same as the underlying
* attr
*/
to->attnum = i + 1;
to->attstattarget = -1;
to->attcacheoff = -1;
to->attnotnull = false;
to->atthasdef = false;
to->attislocal = true;
to->attinhcount = 0;
to->attcollation = collationObjectId[i];
}
else
{
/* Expressional index */
Node *indexkey;
MemSet(to, 0, ATTRIBUTE_FIXED_PART_SIZE);
if (indexpr_item == NULL) /* shouldn't happen */
elog(ERROR, "too few entries in indexprs list");
indexkey = (Node *) lfirst(indexpr_item);
indexpr_item = lnext(indexpr_item);
/*
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* Lookup the expression type in pg_type for the type length etc.
*/
keyType = exprType(indexkey);
tuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(keyType));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for type %u", keyType);
typeTup = (Form_pg_type) GETSTRUCT(tuple);
/*
* Assign some of the attributes values. Leave the rest as 0.
*/
to->attnum = i + 1;
to->atttypid = keyType;
to->attlen = typeTup->typlen;
to->attbyval = typeTup->typbyval;
to->attstorage = typeTup->typstorage;
to->attalign = typeTup->typalign;
to->attstattarget = -1;
to->attcacheoff = -1;
to->atttypmod = -1;
to->attislocal = true;
to->attcollation = collationObjectId[i];
ReleaseSysCache(tuple);
/*
* Make sure the expression yields a type that's safe to store in
* an index. We need this defense because we have index opclasses
* for pseudo-types such as "record", and the actually stored type
* had better be safe; eg, a named composite type is okay, an
* anonymous record type is not. The test is the same as for
* whether a table column is of a safe type (which is why we
* needn't check for the non-expression case).
*/
CheckAttributeType(NameStr(to->attname),
to->atttypid, to->attcollation,
NIL, false);
}
/*
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* We do not yet have the correct relation OID for the index, so just
* set it invalid for now. InitializeAttributeOids() will fix it
* later.
*/
to->attrelid = InvalidOid;
/*
* Set the attribute name as specified by caller.
*/
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if (colnames_item == NULL) /* shouldn't happen */
elog(ERROR, "too few entries in colnames list");
namestrcpy(&to->attname, (const char *) lfirst(colnames_item));
colnames_item = lnext(colnames_item);
/*
* Check the opclass and index AM to see if either provides a keytype
* (overriding the attribute type). Opclass takes precedence.
*/
tuple = SearchSysCache1(CLAOID, ObjectIdGetDatum(classObjectId[i]));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for opclass %u",
classObjectId[i]);
opclassTup = (Form_pg_opclass) GETSTRUCT(tuple);
if (OidIsValid(opclassTup->opckeytype))
keyType = opclassTup->opckeytype;
else
keyType = amform->amkeytype;
ReleaseSysCache(tuple);
if (OidIsValid(keyType) && keyType != to->atttypid)
{
/* index value and heap value have different types */
tuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(keyType));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for type %u", keyType);
typeTup = (Form_pg_type) GETSTRUCT(tuple);
to->atttypid = keyType;
to->atttypmod = -1;
to->attlen = typeTup->typlen;
to->attbyval = typeTup->typbyval;
to->attalign = typeTup->typalign;
to->attstorage = typeTup->typstorage;
ReleaseSysCache(tuple);
}
}
ReleaseSysCache(amtuple);
return indexTupDesc;
}
/* ----------------------------------------------------------------
* InitializeAttributeOids
* ----------------------------------------------------------------
*/
static void
InitializeAttributeOids(Relation indexRelation,
int numatts,
Oid indexoid)
{
TupleDesc tupleDescriptor;
int i;
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tupleDescriptor = RelationGetDescr(indexRelation);
for (i = 0; i < numatts; i += 1)
tupleDescriptor->attrs[i]->attrelid = indexoid;
}
/* ----------------------------------------------------------------
* AppendAttributeTuples
* ----------------------------------------------------------------
*/
static void
AppendAttributeTuples(Relation indexRelation, int numatts)
{
Relation pg_attribute;
CatalogIndexState indstate;
TupleDesc indexTupDesc;
int i;
/*
* open the attribute relation and its indexes
*/
pg_attribute = heap_open(AttributeRelationId, RowExclusiveLock);
indstate = CatalogOpenIndexes(pg_attribute);
/*
Clean up various to-do items associated with system indexes: pg_database now has unique indexes on oid and on datname. pg_shadow now has unique indexes on usename and on usesysid. pg_am now has unique index on oid. pg_opclass now has unique index on oid. pg_amproc now has unique index on amid+amopclaid+amprocnum. Remove pg_rewrite's unnecessary index on oid, delete unused RULEOID syscache. Remove index on pg_listener and associated syscache for performance reasons (caching rows that are certain to change before you need 'em again is rather pointless). Change pg_attrdef's nonunique index on adrelid into a unique index on adrelid+adnum. Fix various incorrect settings of pg_class.relisshared, make that the primary reference point for whether a relation is shared or not. IsSharedSystemRelationName() is now only consulted to initialize relisshared during initial creation of tables and indexes. In theory we might now support shared user relations, though it's not clear how one would get entries for them into pg_class &etc of multiple databases. Fix recently reported bug that pg_attribute rows created for an index all have the same OID. (Proof that non-unique OID doesn't matter unless it's actually used to do lookups ;-)) There's no need to treat pg_trigger, pg_attrdef, pg_relcheck as bootstrap relations. Convert them into plain system catalogs without hardwired entries in pg_class and friends. Unify global.bki and template1.bki into a single init script postgres.bki, since the alleged distinction between them was misleading and pointless. Not to mention that it didn't work for setting up indexes on shared system relations. Rationalize locking of pg_shadow, pg_group, pg_attrdef (no need to use AccessExclusiveLock where ExclusiveLock or even RowExclusiveLock will do). Also, hold locks until transaction commit where necessary.
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* insert data from new index's tupdesc into pg_attribute
*/
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indexTupDesc = RelationGetDescr(indexRelation);
Clean up various to-do items associated with system indexes: pg_database now has unique indexes on oid and on datname. pg_shadow now has unique indexes on usename and on usesysid. pg_am now has unique index on oid. pg_opclass now has unique index on oid. pg_amproc now has unique index on amid+amopclaid+amprocnum. Remove pg_rewrite's unnecessary index on oid, delete unused RULEOID syscache. Remove index on pg_listener and associated syscache for performance reasons (caching rows that are certain to change before you need 'em again is rather pointless). Change pg_attrdef's nonunique index on adrelid into a unique index on adrelid+adnum. Fix various incorrect settings of pg_class.relisshared, make that the primary reference point for whether a relation is shared or not. IsSharedSystemRelationName() is now only consulted to initialize relisshared during initial creation of tables and indexes. In theory we might now support shared user relations, though it's not clear how one would get entries for them into pg_class &etc of multiple databases. Fix recently reported bug that pg_attribute rows created for an index all have the same OID. (Proof that non-unique OID doesn't matter unless it's actually used to do lookups ;-)) There's no need to treat pg_trigger, pg_attrdef, pg_relcheck as bootstrap relations. Convert them into plain system catalogs without hardwired entries in pg_class and friends. Unify global.bki and template1.bki into a single init script postgres.bki, since the alleged distinction between them was misleading and pointless. Not to mention that it didn't work for setting up indexes on shared system relations. Rationalize locking of pg_shadow, pg_group, pg_attrdef (no need to use AccessExclusiveLock where ExclusiveLock or even RowExclusiveLock will do). Also, hold locks until transaction commit where necessary.
2001-06-12 07:55:50 +02:00
for (i = 0; i < numatts; i++)
{
/*
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* There used to be very grotty code here to set these fields, but I
* think it's unnecessary. They should be set already.
*/
Assert(indexTupDesc->attrs[i]->attnum == i + 1);
Clean up various to-do items associated with system indexes: pg_database now has unique indexes on oid and on datname. pg_shadow now has unique indexes on usename and on usesysid. pg_am now has unique index on oid. pg_opclass now has unique index on oid. pg_amproc now has unique index on amid+amopclaid+amprocnum. Remove pg_rewrite's unnecessary index on oid, delete unused RULEOID syscache. Remove index on pg_listener and associated syscache for performance reasons (caching rows that are certain to change before you need 'em again is rather pointless). Change pg_attrdef's nonunique index on adrelid into a unique index on adrelid+adnum. Fix various incorrect settings of pg_class.relisshared, make that the primary reference point for whether a relation is shared or not. IsSharedSystemRelationName() is now only consulted to initialize relisshared during initial creation of tables and indexes. In theory we might now support shared user relations, though it's not clear how one would get entries for them into pg_class &etc of multiple databases. Fix recently reported bug that pg_attribute rows created for an index all have the same OID. (Proof that non-unique OID doesn't matter unless it's actually used to do lookups ;-)) There's no need to treat pg_trigger, pg_attrdef, pg_relcheck as bootstrap relations. Convert them into plain system catalogs without hardwired entries in pg_class and friends. Unify global.bki and template1.bki into a single init script postgres.bki, since the alleged distinction between them was misleading and pointless. Not to mention that it didn't work for setting up indexes on shared system relations. Rationalize locking of pg_shadow, pg_group, pg_attrdef (no need to use AccessExclusiveLock where ExclusiveLock or even RowExclusiveLock will do). Also, hold locks until transaction commit where necessary.
2001-06-12 07:55:50 +02:00
Assert(indexTupDesc->attrs[i]->attcacheoff == -1);
InsertPgAttributeTuple(pg_attribute, indexTupDesc->attrs[i], indstate);
}
CatalogCloseIndexes(indstate);
Clean up various to-do items associated with system indexes: pg_database now has unique indexes on oid and on datname. pg_shadow now has unique indexes on usename and on usesysid. pg_am now has unique index on oid. pg_opclass now has unique index on oid. pg_amproc now has unique index on amid+amopclaid+amprocnum. Remove pg_rewrite's unnecessary index on oid, delete unused RULEOID syscache. Remove index on pg_listener and associated syscache for performance reasons (caching rows that are certain to change before you need 'em again is rather pointless). Change pg_attrdef's nonunique index on adrelid into a unique index on adrelid+adnum. Fix various incorrect settings of pg_class.relisshared, make that the primary reference point for whether a relation is shared or not. IsSharedSystemRelationName() is now only consulted to initialize relisshared during initial creation of tables and indexes. In theory we might now support shared user relations, though it's not clear how one would get entries for them into pg_class &etc of multiple databases. Fix recently reported bug that pg_attribute rows created for an index all have the same OID. (Proof that non-unique OID doesn't matter unless it's actually used to do lookups ;-)) There's no need to treat pg_trigger, pg_attrdef, pg_relcheck as bootstrap relations. Convert them into plain system catalogs without hardwired entries in pg_class and friends. Unify global.bki and template1.bki into a single init script postgres.bki, since the alleged distinction between them was misleading and pointless. Not to mention that it didn't work for setting up indexes on shared system relations. Rationalize locking of pg_shadow, pg_group, pg_attrdef (no need to use AccessExclusiveLock where ExclusiveLock or even RowExclusiveLock will do). Also, hold locks until transaction commit where necessary.
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heap_close(pg_attribute, RowExclusiveLock);
}
/* ----------------------------------------------------------------
* UpdateIndexRelation
*
* Construct and insert a new entry in the pg_index catalog
* ----------------------------------------------------------------
*/
static void
UpdateIndexRelation(Oid indexoid,
Oid heapoid,
IndexInfo *indexInfo,
Oid *collationOids,
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Oid *classOids,
int16 *coloptions,
bool primary,
bool isexclusion,
bool immediate,
bool isvalid)
{
int2vector *indkey;
oidvector *indcollation;
oidvector *indclass;
int2vector *indoption;
Datum exprsDatum;
Datum predDatum;
Datum values[Natts_pg_index];
bool nulls[Natts_pg_index];
Relation pg_index;
HeapTuple tuple;
int i;
/*
* Copy the index key, opclass, and indoption info into arrays (should we
* make the caller pass them like this to start with?)
*/
indkey = buildint2vector(NULL, indexInfo->ii_NumIndexAttrs);
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
indkey->values[i] = indexInfo->ii_KeyAttrNumbers[i];
indcollation = buildoidvector(collationOids, indexInfo->ii_NumIndexAttrs);
indclass = buildoidvector(classOids, indexInfo->ii_NumIndexAttrs);
indoption = buildint2vector(coloptions, indexInfo->ii_NumIndexAttrs);
/*
* Convert the index expressions (if any) to a text datum
*/
if (indexInfo->ii_Expressions != NIL)
{
char *exprsString;
exprsString = nodeToString(indexInfo->ii_Expressions);
exprsDatum = CStringGetTextDatum(exprsString);
pfree(exprsString);
}
else
exprsDatum = (Datum) 0;
/*
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* Convert the index predicate (if any) to a text datum. Note we convert
* implicit-AND format to normal explicit-AND for storage.
*/
if (indexInfo->ii_Predicate != NIL)
{
char *predString;
predString = nodeToString(make_ands_explicit(indexInfo->ii_Predicate));
predDatum = CStringGetTextDatum(predString);
pfree(predString);
}
else
predDatum = (Datum) 0;
/*
* open the system catalog index relation
*/
pg_index = heap_open(IndexRelationId, RowExclusiveLock);
/*
* Build a pg_index tuple
*/
MemSet(nulls, false, sizeof(nulls));
values[Anum_pg_index_indexrelid - 1] = ObjectIdGetDatum(indexoid);
values[Anum_pg_index_indrelid - 1] = ObjectIdGetDatum(heapoid);
values[Anum_pg_index_indnatts - 1] = Int16GetDatum(indexInfo->ii_NumIndexAttrs);
values[Anum_pg_index_indisunique - 1] = BoolGetDatum(indexInfo->ii_Unique);
values[Anum_pg_index_indisprimary - 1] = BoolGetDatum(primary);
values[Anum_pg_index_indisexclusion - 1] = BoolGetDatum(isexclusion);
values[Anum_pg_index_indimmediate - 1] = BoolGetDatum(immediate);
values[Anum_pg_index_indisclustered - 1] = BoolGetDatum(false);
values[Anum_pg_index_indisvalid - 1] = BoolGetDatum(isvalid);
values[Anum_pg_index_indcheckxmin - 1] = BoolGetDatum(false);
/* we set isvalid and isready the same way */
values[Anum_pg_index_indisready - 1] = BoolGetDatum(isvalid);
values[Anum_pg_index_indkey - 1] = PointerGetDatum(indkey);
values[Anum_pg_index_indcollation - 1] = PointerGetDatum(indcollation);
values[Anum_pg_index_indclass - 1] = PointerGetDatum(indclass);
values[Anum_pg_index_indoption - 1] = PointerGetDatum(indoption);
values[Anum_pg_index_indexprs - 1] = exprsDatum;
if (exprsDatum == (Datum) 0)
nulls[Anum_pg_index_indexprs - 1] = true;
values[Anum_pg_index_indpred - 1] = predDatum;
if (predDatum == (Datum) 0)
nulls[Anum_pg_index_indpred - 1] = true;
tuple = heap_form_tuple(RelationGetDescr(pg_index), values, nulls);
/*
* insert the tuple into the pg_index catalog
*/
simple_heap_insert(pg_index, tuple);
/* update the indexes on pg_index */
CatalogUpdateIndexes(pg_index, tuple);
/*
* close the relation and free the tuple
*/
heap_close(pg_index, RowExclusiveLock);
heap_freetuple(tuple);
}
/*
* index_create
*
* heapRelation: table to build index on (suitably locked by caller)
* indexRelationName: what it say
* indexRelationId: normally, pass InvalidOid to let this routine
* generate an OID for the index. During bootstrap this may be
* nonzero to specify a preselected OID.
* indexInfo: same info executor uses to insert into the index
* indexColNames: column names to use for index (List of char *)
* accessMethodObjectId: OID of index AM to use
* tableSpaceId: OID of tablespace to use
* collationObjectId: array of collation OIDs, one per index column
* classObjectId: array of index opclass OIDs, one per index column
* coloptions: array of per-index-column indoption settings
* reloptions: AM-specific options
* isprimary: index is a PRIMARY KEY
* isconstraint: index is owned by PRIMARY KEY, UNIQUE, or EXCLUSION constraint
* deferrable: constraint is DEFERRABLE
* initdeferred: constraint is INITIALLY DEFERRED
* allow_system_table_mods: allow table to be a system catalog
* skip_build: true to skip the index_build() step for the moment; caller
* must do it later (typically via reindex_index())
2006-10-04 02:30:14 +02:00
* concurrent: if true, do not lock the table against writers. The index
* will be marked "invalid" and the caller must take additional steps
* to fix it up.
*
* Returns the OID of the created index.
*/
Oid
index_create(Relation heapRelation,
const char *indexRelationName,
Oid indexRelationId,
IndexInfo *indexInfo,
List *indexColNames,
Oid accessMethodObjectId,
Oid tableSpaceId,
Oid *collationObjectId,
1998-09-01 05:29:17 +02:00
Oid *classObjectId,
int16 *coloptions,
Datum reloptions,
bool isprimary,
bool isconstraint,
bool deferrable,
bool initdeferred,
bool allow_system_table_mods,
bool skip_build,
bool concurrent)
{
Oid heapRelationId = RelationGetRelid(heapRelation);
Relation pg_class;
Relation indexRelation;
TupleDesc indexTupDesc;
bool shared_relation;
bool mapped_relation;
bool is_exclusion;
Oid namespaceId;
int i;
char relpersistence;
1999-05-25 18:15:34 +02:00
is_exclusion = (indexInfo->ii_ExclusionOps != NULL);
pg_class = heap_open(RelationRelationId, RowExclusiveLock);
/*
2002-09-04 22:31:48 +02:00
* The index will be in the same namespace as its parent table, and is
2010-02-26 03:01:40 +01:00
* shared across databases if and only if the parent is. Likewise, it
* will use the relfilenode map if and only if the parent does; and it
* inherits the parent's relpersistence.
*/
namespaceId = RelationGetNamespace(heapRelation);
shared_relation = heapRelation->rd_rel->relisshared;
mapped_relation = RelationIsMapped(heapRelation);
relpersistence = heapRelation->rd_rel->relpersistence;
/*
* check parameters
*/
if (indexInfo->ii_NumIndexAttrs < 1)
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elog(ERROR, "must index at least one column");
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if (!allow_system_table_mods &&
IsSystemRelation(heapRelation) &&
IsNormalProcessingMode())
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("user-defined indexes on system catalog tables are not supported")));
/*
2006-10-04 02:30:14 +02:00
* concurrent index build on a system catalog is unsafe because we tend to
* release locks before committing in catalogs
*/
if (concurrent &&
IsSystemRelation(heapRelation))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("concurrent index creation on system catalog tables is not supported")));
/*
2010-02-26 03:01:40 +01:00
* This case is currently not supported, but there's no way to ask for it
* in the grammar anyway, so it can't happen.
*/
if (concurrent && is_exclusion)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg_internal("concurrent index creation for exclusion constraints is not supported")));
/*
* We cannot allow indexing a shared relation after initdb (because
* there's no way to make the entry in other databases' pg_class).
*/
if (shared_relation && !IsBootstrapProcessingMode())
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
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errmsg("shared indexes cannot be created after initdb")));
/*
* Shared relations must be in pg_global, too (last-ditch check)
*/
if (shared_relation && tableSpaceId != GLOBALTABLESPACE_OID)
elog(ERROR, "shared relations must be placed in pg_global tablespace");
if (get_relname_relid(indexRelationName, namespaceId))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
errmsg("relation \"%s\" already exists",
indexRelationName)));
/*
* construct tuple descriptor for index tuples
*/
indexTupDesc = ConstructTupleDescriptor(heapRelation,
indexInfo,
indexColNames,
accessMethodObjectId,
collationObjectId,
classObjectId);
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/*
* Allocate an OID for the index, unless we were told what to use.
*
* The OID will be the relfilenode as well, so make sure it doesn't
* collide with either pg_class OIDs or existing physical files.
*/
if (!OidIsValid(indexRelationId))
{
/*
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* Use binary-upgrade override for pg_class.oid/relfilenode, if
* supplied.
*/
if (IsBinaryUpgrade &&
OidIsValid(binary_upgrade_next_index_pg_class_oid))
{
indexRelationId = binary_upgrade_next_index_pg_class_oid;
binary_upgrade_next_index_pg_class_oid = InvalidOid;
}
else
{
indexRelationId =
GetNewRelFileNode(tableSpaceId, pg_class, relpersistence);
}
}
/*
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* create the index relation's relcache entry and physical disk file. (If
* we fail further down, it's the smgr's responsibility to remove the disk
* file again.)
*/
indexRelation = heap_create(indexRelationName,
namespaceId,
tableSpaceId,
indexRelationId,
indexTupDesc,
RELKIND_INDEX,
relpersistence,
shared_relation,
mapped_relation,
allow_system_table_mods);
Assert(indexRelationId == RelationGetRelid(indexRelation));
/*
* Obtain exclusive lock on it. Although no other backends can see it
* until we commit, this prevents deadlock-risk complaints from lock
* manager in cases such as CLUSTER.
*/
LockRelation(indexRelation, AccessExclusiveLock);
/*
2005-10-15 04:49:52 +02:00
* Fill in fields of the index's pg_class entry that are not set correctly
* by heap_create.
*
* XXX should have a cleaner way to create cataloged indexes
*/
indexRelation->rd_rel->relowner = heapRelation->rd_rel->relowner;
indexRelation->rd_rel->relam = accessMethodObjectId;
indexRelation->rd_rel->relkind = RELKIND_INDEX;
indexRelation->rd_rel->relhasoids = false;
/*
* store index's pg_class entry
*/
InsertPgClassTuple(pg_class, indexRelation,
RelationGetRelid(indexRelation),
(Datum) 0,
reloptions);
/* done with pg_class */
heap_close(pg_class, RowExclusiveLock);
/*
* now update the object id's of all the attribute tuple forms in the
* index relation's tuple descriptor
*/
InitializeAttributeOids(indexRelation,
indexInfo->ii_NumIndexAttrs,
indexRelationId);
/*
* append ATTRIBUTE tuples for the index
*/
AppendAttributeTuples(indexRelation, indexInfo->ii_NumIndexAttrs);
/* ----------------
* update pg_index
* (append INDEX tuple)
*
* Note that this stows away a representation of "predicate".
* (Or, could define a rule to maintain the predicate) --Nels, Feb '92
* ----------------
*/
UpdateIndexRelation(indexRelationId, heapRelationId, indexInfo,
collationObjectId, classObjectId, coloptions,
isprimary, is_exclusion,
!deferrable,
!concurrent);
/*
* Register constraint and dependencies for the index.
*
* If the index is from a CONSTRAINT clause, construct a pg_constraint
* entry. The index will be linked to the constraint, which in turn is
* linked to the table. If it's not a CONSTRAINT, we need to make a
* dependency directly on the table.
*
2002-09-04 22:31:48 +02:00
* We don't need a dependency on the namespace, because there'll be an
* indirect dependency via our parent table.
*
* During bootstrap we can't register any dependencies, and we don't try
* to make a constraint either.
*/
if (!IsBootstrapProcessingMode())
{
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ObjectAddress myself,
referenced;
myself.classId = RelationRelationId;
myself.objectId = indexRelationId;
myself.objectSubId = 0;
if (isconstraint)
{
char constraintType;
if (isprimary)
constraintType = CONSTRAINT_PRIMARY;
else if (indexInfo->ii_Unique)
constraintType = CONSTRAINT_UNIQUE;
else if (is_exclusion)
constraintType = CONSTRAINT_EXCLUSION;
else
{
elog(ERROR, "constraint must be PRIMARY, UNIQUE or EXCLUDE");
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constraintType = 0; /* keep compiler quiet */
}
index_constraint_create(heapRelation,
indexRelationId,
indexInfo,
indexRelationName,
constraintType,
deferrable,
initdeferred,
false, /* already marked primary */
false, /* pg_index entry is OK */
allow_system_table_mods);
}
else
{
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bool have_simple_col = false;
/* Create auto dependencies on simply-referenced columns */
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
if (indexInfo->ii_KeyAttrNumbers[i] != 0)
{
referenced.classId = RelationRelationId;
referenced.objectId = heapRelationId;
referenced.objectSubId = indexInfo->ii_KeyAttrNumbers[i];
recordDependencyOn(&myself, &referenced, DEPENDENCY_AUTO);
have_simple_col = true;
}
}
/*
* If there are no simply-referenced columns, give the index an
2011-04-10 17:42:00 +02:00
* auto dependency on the whole table. In most cases, this will
* be redundant, but it might not be if the index expressions and
* predicate contain no Vars or only whole-row Vars.
*/
if (!have_simple_col)
{
referenced.classId = RelationRelationId;
referenced.objectId = heapRelationId;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_AUTO);
}
/* Non-constraint indexes can't be deferrable */
Assert(!deferrable);
Assert(!initdeferred);
}
/* Store dependency on collations */
/* The default collation is pinned, so don't bother recording it */
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
if (OidIsValid(collationObjectId[i]) &&
collationObjectId[i] != DEFAULT_COLLATION_OID)
{
referenced.classId = CollationRelationId;
referenced.objectId = collationObjectId[i];
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
}
/* Store dependency on operator classes */
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
referenced.classId = OperatorClassRelationId;
referenced.objectId = classObjectId[i];
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
/* Store dependencies on anything mentioned in index expressions */
if (indexInfo->ii_Expressions)
{
recordDependencyOnSingleRelExpr(&myself,
2005-10-15 04:49:52 +02:00
(Node *) indexInfo->ii_Expressions,
heapRelationId,
DEPENDENCY_NORMAL,
DEPENDENCY_AUTO);
}
/* Store dependencies on anything mentioned in predicate */
if (indexInfo->ii_Predicate)
{
recordDependencyOnSingleRelExpr(&myself,
2005-10-15 04:49:52 +02:00
(Node *) indexInfo->ii_Predicate,
heapRelationId,
DEPENDENCY_NORMAL,
DEPENDENCY_AUTO);
}
}
else
{
/* Bootstrap mode - assert we weren't asked for constraint support */
Assert(!isconstraint);
Assert(!deferrable);
Assert(!initdeferred);
}
/*
* Advance the command counter so that we can see the newly-entered
* catalog tuples for the index.
*/
CommandCounterIncrement();
/*
2005-10-15 04:49:52 +02:00
* In bootstrap mode, we have to fill in the index strategy structure with
* information from the catalogs. If we aren't bootstrapping, then the
* relcache entry has already been rebuilt thanks to sinval update during
* CommandCounterIncrement.
*/
if (IsBootstrapProcessingMode())
RelationInitIndexAccessInfo(indexRelation);
else
Assert(indexRelation->rd_indexcxt != NULL);
/*
2005-10-15 04:49:52 +02:00
* If this is bootstrap (initdb) time, then we don't actually fill in the
* index yet. We'll be creating more indexes and classes later, so we
* delay filling them in until just before we're done with bootstrapping.
* Similarly, if the caller specified skip_build then filling the index is
* delayed till later (ALTER TABLE can save work in some cases with this).
* Otherwise, we call the AM routine that constructs the index.
*/
if (IsBootstrapProcessingMode())
{
index_register(heapRelationId, indexRelationId, indexInfo);
}
else if (skip_build)
{
/*
* Caller is responsible for filling the index later on. However,
2006-10-04 02:30:14 +02:00
* we'd better make sure that the heap relation is correctly marked as
* having an index.
*/
index_update_stats(heapRelation,
true,
isprimary,
InvalidOid,
heapRelation->rd_rel->reltuples);
/* Make the above update visible */
CommandCounterIncrement();
}
else
{
index_build(heapRelation, indexRelation, indexInfo, isprimary, false);
}
/*
* Close the index; but we keep the lock that we acquired above until end
2011-04-10 17:42:00 +02:00
* of transaction. Closing the heap is caller's responsibility.
*/
index_close(indexRelation, NoLock);
return indexRelationId;
}
/*
* index_constraint_create
*
* Set up a constraint associated with an index
*
* heapRelation: table owning the index (must be suitably locked by caller)
* indexRelationId: OID of the index
* indexInfo: same info executor uses to insert into the index
* constraintName: what it say (generally, should match name of index)
* constraintType: one of CONSTRAINT_PRIMARY, CONSTRAINT_UNIQUE, or
* CONSTRAINT_EXCLUSION
* deferrable: constraint is DEFERRABLE
* initdeferred: constraint is INITIALLY DEFERRED
* mark_as_primary: if true, set flags to mark index as primary key
* update_pgindex: if true, update pg_index row (else caller's done that)
* allow_system_table_mods: allow table to be a system catalog
*/
void
index_constraint_create(Relation heapRelation,
Oid indexRelationId,
IndexInfo *indexInfo,
const char *constraintName,
char constraintType,
bool deferrable,
bool initdeferred,
bool mark_as_primary,
bool update_pgindex,
bool allow_system_table_mods)
{
Oid namespaceId = RelationGetNamespace(heapRelation);
ObjectAddress myself,
referenced;
Oid conOid;
/* constraint creation support doesn't work while bootstrapping */
Assert(!IsBootstrapProcessingMode());
/* enforce system-table restriction */
if (!allow_system_table_mods &&
IsSystemRelation(heapRelation) &&
IsNormalProcessingMode())
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("user-defined indexes on system catalog tables are not supported")));
/* primary/unique constraints shouldn't have any expressions */
if (indexInfo->ii_Expressions &&
constraintType != CONSTRAINT_EXCLUSION)
elog(ERROR, "constraints cannot have index expressions");
/*
* Construct a pg_constraint entry.
*/
conOid = CreateConstraintEntry(constraintName,
namespaceId,
constraintType,
deferrable,
initdeferred,
true,
RelationGetRelid(heapRelation),
indexInfo->ii_KeyAttrNumbers,
indexInfo->ii_NumIndexAttrs,
InvalidOid, /* no domain */
indexRelationId, /* index OID */
InvalidOid, /* no foreign key */
NULL,
NULL,
NULL,
NULL,
0,
' ',
' ',
' ',
indexInfo->ii_ExclusionOps,
NULL, /* no check constraint */
NULL,
NULL,
true, /* islocal */
0); /* inhcount */
/*
* Register the index as internally dependent on the constraint.
*
* Note that the constraint has a dependency on the table, so when this
* path is taken we do not need any direct dependency from the index to
* the table. (But if one exists, no great harm is done, either. So in
* the case where we're manufacturing a constraint for a pre-existing
* index, we don't bother to try to get rid of the existing index->table
* dependency.)
*/
myself.classId = RelationRelationId;
myself.objectId = indexRelationId;
myself.objectSubId = 0;
referenced.classId = ConstraintRelationId;
referenced.objectId = conOid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_INTERNAL);
/*
* If the constraint is deferrable, create the deferred uniqueness
2011-04-10 17:42:00 +02:00
* checking trigger. (The trigger will be given an internal dependency on
* the constraint by CreateTrigger.)
*/
if (deferrable)
{
RangeVar *heapRel;
CreateTrigStmt *trigger;
heapRel = makeRangeVar(get_namespace_name(namespaceId),
pstrdup(RelationGetRelationName(heapRelation)),
-1);
trigger = makeNode(CreateTrigStmt);
trigger->trigname = (constraintType == CONSTRAINT_PRIMARY) ?
"PK_ConstraintTrigger" :
"Unique_ConstraintTrigger";
trigger->relation = heapRel;
trigger->funcname = SystemFuncName("unique_key_recheck");
trigger->args = NIL;
trigger->row = true;
trigger->timing = TRIGGER_TYPE_AFTER;
trigger->events = TRIGGER_TYPE_INSERT | TRIGGER_TYPE_UPDATE;
trigger->columns = NIL;
trigger->whenClause = NULL;
trigger->isconstraint = true;
trigger->deferrable = true;
trigger->initdeferred = initdeferred;
trigger->constrrel = NULL;
(void) CreateTrigger(trigger, NULL, conOid, indexRelationId, true);
}
/*
* If needed, mark the table as having a primary key. We assume it can't
* have been so marked already, so no need to clear the flag in the other
* case.
*
2011-04-10 17:42:00 +02:00
* Note: this might better be done by callers. We do it here to avoid
* exposing index_update_stats() globally, but that wouldn't be necessary
* if relhaspkey went away.
*/
if (mark_as_primary)
index_update_stats(heapRelation,
true,
true,
InvalidOid,
heapRelation->rd_rel->reltuples);
/*
* If needed, mark the index as primary and/or deferred in pg_index.
*
* Note: since this is a transactional update, it's unsafe against
* concurrent SnapshotNow scans of pg_index. When making an existing
* index into a constraint, caller must have a table lock that prevents
* concurrent table updates, and there is a risk that concurrent readers
* of the table will miss seeing this index at all.
*/
if (update_pgindex && (mark_as_primary || deferrable))
{
2011-04-10 17:42:00 +02:00
Relation pg_index;
HeapTuple indexTuple;
Form_pg_index indexForm;
bool dirty = false;
pg_index = heap_open(IndexRelationId, RowExclusiveLock);
indexTuple = SearchSysCacheCopy1(INDEXRELID,
ObjectIdGetDatum(indexRelationId));
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "cache lookup failed for index %u", indexRelationId);
indexForm = (Form_pg_index) GETSTRUCT(indexTuple);
if (mark_as_primary && !indexForm->indisprimary)
{
indexForm->indisprimary = true;
dirty = true;
}
if (deferrable && indexForm->indimmediate)
{
indexForm->indimmediate = false;
dirty = true;
}
if (dirty)
{
simple_heap_update(pg_index, &indexTuple->t_self, indexTuple);
CatalogUpdateIndexes(pg_index, indexTuple);
}
heap_freetuple(indexTuple);
heap_close(pg_index, RowExclusiveLock);
}
}
/*
* index_drop
*
* NOTE: this routine should now only be called through performDeletion(),
* else associated dependencies won't be cleaned up.
*/
void
index_drop(Oid indexId)
{
Oid heapId;
Relation userHeapRelation;
Relation userIndexRelation;
Relation indexRelation;
HeapTuple tuple;
bool hasexprs;
1999-05-25 18:15:34 +02:00
/*
* To drop an index safely, we must grab exclusive lock on its parent
* table. Exclusive lock on the index alone is insufficient because
* another backend might be about to execute a query on the parent table.
* If it relies on a previously cached list of index OIDs, then it could
* attempt to access the just-dropped index. We must therefore take a
* table lock strong enough to prevent all queries on the table from
* proceeding until we commit and send out a shared-cache-inval notice
* that will make them update their index lists.
*/
heapId = IndexGetRelation(indexId);
userHeapRelation = heap_open(heapId, AccessExclusiveLock);
userIndexRelation = index_open(indexId, AccessExclusiveLock);
/*
2011-04-10 17:42:00 +02:00
* There can no longer be anyone *else* touching the index, but we might
* still have open queries using it in our own session.
*/
CheckTableNotInUse(userIndexRelation, "DROP INDEX");
/*
* Schedule physical removal of the files
*/
RelationDropStorage(userIndexRelation);
2002-09-04 22:31:48 +02:00
/*
2005-10-15 04:49:52 +02:00
* Close and flush the index's relcache entry, to ensure relcache doesn't
* try to rebuild it while we're deleting catalog entries. We keep the
* lock though.
*/
index_close(userIndexRelation, NoLock);
RelationForgetRelation(indexId);
/*
* fix INDEX relation, and check for expressional index
*/
indexRelation = heap_open(IndexRelationId, RowExclusiveLock);
tuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexId));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for index %u", indexId);
1998-08-21 00:07:46 +02:00
hasexprs = !heap_attisnull(tuple, Anum_pg_index_indexprs);
simple_heap_delete(indexRelation, &tuple->t_self);
ReleaseSysCache(tuple);
heap_close(indexRelation, RowExclusiveLock);
/*
2005-10-15 04:49:52 +02:00
* if it has any expression columns, we might have stored statistics about
* them.
*/
if (hasexprs)
RemoveStatistics(indexId, 0);
/*
* fix ATTRIBUTE relation
*/
DeleteAttributeTuples(indexId);
/*
* fix RELATION relation
*/
DeleteRelationTuple(indexId);
/*
2005-10-15 04:49:52 +02:00
* We are presently too lazy to attempt to compute the new correct value
* of relhasindex (the next VACUUM will fix it if necessary). So there is
* no need to update the pg_class tuple for the owning relation. But we
* must send out a shared-cache-inval notice on the owning relation to
* ensure other backends update their relcache lists of indexes.
*/
CacheInvalidateRelcache(userHeapRelation);
/*
* Close owning rel, but keep lock
*/
heap_close(userHeapRelation, NoLock);
}
/* ----------------------------------------------------------------
* index_build support
* ----------------------------------------------------------------
*/
/* ----------------
* BuildIndexInfo
* Construct an IndexInfo record for an open index
*
* IndexInfo stores the information about the index that's needed by
* FormIndexDatum, which is used for both index_build() and later insertion
2001-03-22 05:01:46 +01:00
* of individual index tuples. Normally we build an IndexInfo for an index
* just once per command, and then use it for (potentially) many tuples.
* ----------------
*/
IndexInfo *
BuildIndexInfo(Relation index)
{
IndexInfo *ii = makeNode(IndexInfo);
Form_pg_index indexStruct = index->rd_index;
int i;
int numKeys;
/* check the number of keys, and copy attr numbers into the IndexInfo */
numKeys = indexStruct->indnatts;
if (numKeys < 1 || numKeys > INDEX_MAX_KEYS)
elog(ERROR, "invalid indnatts %d for index %u",
numKeys, RelationGetRelid(index));
ii->ii_NumIndexAttrs = numKeys;
for (i = 0; i < numKeys; i++)
ii->ii_KeyAttrNumbers[i] = indexStruct->indkey.values[i];
/* fetch any expressions needed for expressional indexes */
ii->ii_Expressions = RelationGetIndexExpressions(index);
ii->ii_ExpressionsState = NIL;
/* fetch index predicate if any */
ii->ii_Predicate = RelationGetIndexPredicate(index);
ii->ii_PredicateState = NIL;
/* fetch exclusion constraint info if any */
if (indexStruct->indisexclusion)
{
RelationGetExclusionInfo(index,
&ii->ii_ExclusionOps,
&ii->ii_ExclusionProcs,
&ii->ii_ExclusionStrats);
}
else
{
ii->ii_ExclusionOps = NULL;
ii->ii_ExclusionProcs = NULL;
ii->ii_ExclusionStrats = NULL;
}
/* other info */
ii->ii_Unique = indexStruct->indisunique;
ii->ii_ReadyForInserts = indexStruct->indisready;
/* initialize index-build state to default */
ii->ii_Concurrent = false;
ii->ii_BrokenHotChain = false;
return ii;
}
/* ----------------
* FormIndexDatum
* Construct values[] and isnull[] arrays for a new index tuple.
*
* indexInfo Info about the index
* slot Heap tuple for which we must prepare an index entry
* estate executor state for evaluating any index expressions
* values Array of index Datums (output area)
* isnull Array of is-null indicators (output area)
*
* When there are no index expressions, estate may be NULL. Otherwise it
* must be supplied, *and* the ecxt_scantuple slot of its per-tuple expr
* context must point to the heap tuple passed in.
*
* Notice we don't actually call index_form_tuple() here; we just prepare
2005-10-15 04:49:52 +02:00
* its input arrays values[] and isnull[]. This is because the index AM
* may wish to alter the data before storage.
* ----------------
*/
void
FormIndexDatum(IndexInfo *indexInfo,
TupleTableSlot *slot,
EState *estate,
Datum *values,
bool *isnull)
{
ListCell *indexpr_item;
int i;
if (indexInfo->ii_Expressions != NIL &&
indexInfo->ii_ExpressionsState == NIL)
{
/* First time through, set up expression evaluation state */
indexInfo->ii_ExpressionsState = (List *)
ExecPrepareExpr((Expr *) indexInfo->ii_Expressions,
estate);
/* Check caller has set up context correctly */
Assert(GetPerTupleExprContext(estate)->ecxt_scantuple == slot);
}
indexpr_item = list_head(indexInfo->ii_ExpressionsState);
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
int keycol = indexInfo->ii_KeyAttrNumbers[i];
Datum iDatum;
bool isNull;
1998-08-28 06:57:21 +02:00
if (keycol != 0)
{
/*
* Plain index column; get the value we need directly from the
* heap tuple.
*/
iDatum = slot_getattr(slot, keycol, &isNull);
}
else
{
/*
* Index expression --- need to evaluate it.
*/
if (indexpr_item == NULL)
elog(ERROR, "wrong number of index expressions");
iDatum = ExecEvalExprSwitchContext((ExprState *) lfirst(indexpr_item),
2005-10-15 04:49:52 +02:00
GetPerTupleExprContext(estate),
&isNull,
NULL);
indexpr_item = lnext(indexpr_item);
}
values[i] = iDatum;
isnull[i] = isNull;
}
if (indexpr_item != NULL)
elog(ERROR, "wrong number of index expressions");
}
/*
* index_update_stats --- update pg_class entry after CREATE INDEX or REINDEX
*
* This routine updates the pg_class row of either an index or its parent
2006-10-04 02:30:14 +02:00
* relation after CREATE INDEX or REINDEX. Its rather bizarre API is designed
* to ensure we can do all the necessary work in just one update.
*
* hasindex: set relhasindex to this value
* isprimary: if true, set relhaspkey true; else no change
* reltoastidxid: if not InvalidOid, set reltoastidxid to this value;
* else no change
* reltuples: set reltuples to this value
*
* relpages is also updated (using RelationGetNumberOfBlocks()).
*
* NOTE: an important side-effect of this operation is that an SI invalidation
* message is sent out to all backends --- including me --- causing relcache
2006-10-04 02:30:14 +02:00
* entries to be flushed or updated with the new data. This must happen even
* if we find that no change is needed in the pg_class row. When updating
* a heap entry, this ensures that other backends find out about the new
* index. When updating an index, it's important because some index AMs
* expect a relcache flush to occur after REINDEX.
2000-02-18 10:30:20 +01:00
*/
static void
index_update_stats(Relation rel,
bool hasindex, bool isprimary,
Oid reltoastidxid, double reltuples)
2000-02-18 10:30:20 +01:00
{
2006-10-04 02:30:14 +02:00
BlockNumber relpages = RelationGetNumberOfBlocks(rel);
Oid relid = RelationGetRelid(rel);
2000-02-18 10:30:20 +01:00
Relation pg_class;
HeapTuple tuple;
Form_pg_class rd_rel;
bool dirty;
2000-02-18 10:30:20 +01:00
/*
* We always update the pg_class row using a non-transactional,
* overwrite-in-place update. There are several reasons for this:
*
* 1. In bootstrap mode, we have no choice --- UPDATE wouldn't work.
*
2006-10-04 02:30:14 +02:00
* 2. We could be reindexing pg_class itself, in which case we can't move
* its pg_class row because CatalogUpdateIndexes might not know about all
* the indexes yet (see reindex_relation).
*
* 3. Because we execute CREATE INDEX with just share lock on the parent
* rel (to allow concurrent index creations), an ordinary update could
* suffer a tuple-concurrently-updated failure against another CREATE
* INDEX committing at about the same time. We can avoid that by having
* them both do nontransactional updates (we assume they will both be
* trying to change the pg_class row to the same thing, so it doesn't
* matter which goes first).
*
* 4. Even with just a single CREATE INDEX, there's a risk factor because
* someone else might be trying to open the rel while we commit, and this
* creates a race condition as to whether he will see both or neither of
2006-10-04 02:30:14 +02:00
* the pg_class row versions as valid. Again, a non-transactional update
* avoids the risk. It is indeterminate which state of the row the other
* process will see, but it doesn't matter (if he's only taking
* AccessShareLock, then it's not critical that he see relhasindex true).
*
* It is safe to use a non-transactional update even though our
2006-10-04 02:30:14 +02:00
* transaction could still fail before committing. Setting relhasindex
* true is safe even if there are no indexes (VACUUM will eventually fix
* it), likewise for relhaspkey. And of course the relpages and reltuples
* counts are correct (or at least more so than the old values)
* regardless.
2000-02-18 10:30:20 +01:00
*/
pg_class = heap_open(RelationRelationId, RowExclusiveLock);
/*
2006-10-04 02:30:14 +02:00
* Make a copy of the tuple to update. Normally we use the syscache, but
* we can't rely on that during bootstrap or while reindexing pg_class
* itself.
*/
if (IsBootstrapProcessingMode() ||
ReindexIsProcessingHeap(RelationRelationId))
2000-02-18 10:30:20 +01:00
{
/* don't assume syscache will work */
HeapScanDesc pg_class_scan;
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ScanKeyData key[1];
ScanKeyInit(&key[0],
ObjectIdAttributeNumber,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
2000-02-18 10:30:20 +01:00
pg_class_scan = heap_beginscan(pg_class, SnapshotNow, 1, key);
tuple = heap_getnext(pg_class_scan, ForwardScanDirection);
tuple = heap_copytuple(tuple);
heap_endscan(pg_class_scan);
2000-02-18 10:30:20 +01:00
}
else
{
/* normal case, use syscache */
tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
}
2000-02-18 10:30:20 +01:00
if (!HeapTupleIsValid(tuple))
elog(ERROR, "could not find tuple for relation %u", relid);
rd_rel = (Form_pg_class) GETSTRUCT(tuple);
2000-02-18 10:30:20 +01:00
/* Apply required updates, if any, to copied tuple */
dirty = false;
if (rd_rel->relhasindex != hasindex)
{
rd_rel->relhasindex = hasindex;
dirty = true;
}
if (isprimary)
{
if (!rd_rel->relhaspkey)
{
rd_rel->relhaspkey = true;
dirty = true;
}
}
if (OidIsValid(reltoastidxid))
{
Assert(rd_rel->relkind == RELKIND_TOASTVALUE);
if (rd_rel->reltoastidxid != reltoastidxid)
{
rd_rel->reltoastidxid = reltoastidxid;
dirty = true;
}
}
if (rd_rel->reltuples != (float4) reltuples)
2000-02-18 10:30:20 +01:00
{
rd_rel->reltuples = (float4) reltuples;
dirty = true;
2000-02-18 10:30:20 +01:00
}
if (rd_rel->relpages != (int32) relpages)
2000-02-18 10:30:20 +01:00
{
rd_rel->relpages = (int32) relpages;
dirty = true;
}
/*
* If anything changed, write out the tuple
*/
if (dirty)
{
heap_inplace_update(pg_class, tuple);
/* the above sends a cache inval message */
}
else
{
/* no need to change tuple, but force relcache inval anyway */
CacheInvalidateRelcacheByTuple(tuple);
}
heap_freetuple(tuple);
2000-02-18 10:30:20 +01:00
heap_close(pg_class, RowExclusiveLock);
2000-02-18 10:30:20 +01:00
}
2000-12-08 07:17:58 +01:00
/*
* index_build - invoke access-method-specific index build procedure
*
* On entry, the index's catalog entries are valid, and its physical disk
2006-10-04 02:30:14 +02:00
* file has been created but is empty. We call the AM-specific build
* procedure to fill in the index contents. We then update the pg_class
* entries of the index and heap relation as needed, using statistics
* returned by ambuild as well as data passed by the caller.
*
* isprimary tells whether to mark the index as a primary-key index.
* isreindex indicates we are recreating a previously-existing index.
*
* Note: when reindexing an existing index, isprimary can be false even if
* the index is a PK; it's already properly marked and need not be re-marked.
*
* Note: before Postgres 8.2, the passed-in heap and index Relations
* were automatically closed by this routine. This is no longer the case.
* The caller opened 'em, and the caller should close 'em.
*/
void
index_build(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool isprimary,
bool isreindex)
{
RegProcedure procedure;
IndexBuildResult *stats;
Oid save_userid;
2009-12-09 22:57:51 +01:00
int save_sec_context;
int save_nestlevel;
/*
* sanity checks
*/
Assert(RelationIsValid(indexRelation));
Assert(PointerIsValid(indexRelation->rd_am));
procedure = indexRelation->rd_am->ambuild;
Assert(RegProcedureIsValid(procedure));
ereport(DEBUG1,
(errmsg("building index \"%s\" on table \"%s\"",
RelationGetRelationName(indexRelation),
RelationGetRelationName(heapRelation))));
/*
* Switch to the table owner's userid, so that any index functions are run
2009-12-09 22:57:51 +01:00
* as that user. Also lock down security-restricted operations and
* arrange to make GUC variable changes local to this command.
*/
2009-12-09 22:57:51 +01:00
GetUserIdAndSecContext(&save_userid, &save_sec_context);
SetUserIdAndSecContext(heapRelation->rd_rel->relowner,
save_sec_context | SECURITY_RESTRICTED_OPERATION);
save_nestlevel = NewGUCNestLevel();
/*
* Call the access method's build procedure
*/
stats = (IndexBuildResult *)
DatumGetPointer(OidFunctionCall3(procedure,
PointerGetDatum(heapRelation),
PointerGetDatum(indexRelation),
PointerGetDatum(indexInfo)));
Assert(PointerIsValid(stats));
/*
* If this is an unlogged index, we may need to write out an init fork for
* it -- but we must first check whether one already exists. If, for
* example, an unlogged relation is truncated in the transaction that
* created it, or truncated twice in a subsequent transaction, the
* relfilenode won't change, and nothing needs to be done here.
*/
if (heapRelation->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED
&& !smgrexists(indexRelation->rd_smgr, INIT_FORKNUM))
{
2011-04-10 17:42:00 +02:00
RegProcedure ambuildempty = indexRelation->rd_am->ambuildempty;
RelationOpenSmgr(indexRelation);
smgrcreate(indexRelation->rd_smgr, INIT_FORKNUM, false);
OidFunctionCall1(ambuildempty, PointerGetDatum(indexRelation));
}
/*
2010-02-26 03:01:40 +01:00
* If it's for an exclusion constraint, make a second pass over the heap
* to verify that the constraint is satisfied.
*/
if (indexInfo->ii_ExclusionOps != NULL)
IndexCheckExclusion(heapRelation, indexRelation, indexInfo);
2009-12-09 22:57:51 +01:00
/* Roll back any GUC changes executed by index functions */
AtEOXact_GUC(false, save_nestlevel);
/* Restore userid and security context */
SetUserIdAndSecContext(save_userid, save_sec_context);
/*
2007-11-15 22:14:46 +01:00
* If we found any potentially broken HOT chains, mark the index as not
* being usable until the current transaction is below the event horizon.
* See src/backend/access/heap/README.HOT for discussion.
*
* However, when reindexing an existing index, we should do nothing here.
* Any HOT chains that are broken with respect to the index must predate
* the index's original creation, so there is no need to change the
* index's usability horizon. Moreover, we *must not* try to change
* the index's pg_index entry while reindexing pg_index itself, and this
* optimization nicely prevents that.
*/
if (indexInfo->ii_BrokenHotChain && !isreindex)
{
2007-11-15 22:14:46 +01:00
Oid indexId = RelationGetRelid(indexRelation);
Relation pg_index;
HeapTuple indexTuple;
Form_pg_index indexForm;
pg_index = heap_open(IndexRelationId, RowExclusiveLock);
indexTuple = SearchSysCacheCopy1(INDEXRELID,
ObjectIdGetDatum(indexId));
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "cache lookup failed for index %u", indexId);
indexForm = (Form_pg_index) GETSTRUCT(indexTuple);
/* If it's a new index, indcheckxmin shouldn't be set ... */
Assert(!indexForm->indcheckxmin);
indexForm->indcheckxmin = true;
simple_heap_update(pg_index, &indexTuple->t_self, indexTuple);
CatalogUpdateIndexes(pg_index, indexTuple);
heap_freetuple(indexTuple);
heap_close(pg_index, RowExclusiveLock);
}
/*
* Update heap and index pg_class rows
*/
index_update_stats(heapRelation,
true,
isprimary,
(heapRelation->rd_rel->relkind == RELKIND_TOASTVALUE) ?
RelationGetRelid(indexRelation) : InvalidOid,
stats->heap_tuples);
index_update_stats(indexRelation,
false,
false,
InvalidOid,
stats->index_tuples);
/* Make the updated versions visible */
CommandCounterIncrement();
}
/*
* IndexBuildHeapScan - scan the heap relation to find tuples to be indexed
*
* This is called back from an access-method-specific index build procedure
* after the AM has done whatever setup it needs. The parent heap relation
* is scanned to find tuples that should be entered into the index. Each
* such tuple is passed to the AM's callback routine, which does the right
* things to add it to the new index. After we return, the AM's index
* build procedure does whatever cleanup it needs.
*
* The total count of heap tuples is returned. This is for updating pg_class
* statistics. (It's annoying not to be able to do that here, but we want
* to merge that update with others; see index_update_stats.) Note that the
* index AM itself must keep track of the number of index tuples; we don't do
* so here because the AM might reject some of the tuples for its own reasons,
* such as being unable to store NULLs.
*
* A side effect is to set indexInfo->ii_BrokenHotChain to true if we detect
* any potentially broken HOT chains. Currently, we set this if there are
* any RECENTLY_DEAD or DELETE_IN_PROGRESS entries in a HOT chain, without
* trying very hard to detect whether they're really incompatible with the
* chain tip.
*/
double
IndexBuildHeapScan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
bool allow_sync,
IndexBuildCallback callback,
void *callback_state)
{
bool is_system_catalog;
bool checking_uniqueness;
HeapScanDesc scan;
HeapTuple heapTuple;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
double reltuples;
List *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
Snapshot snapshot;
TransactionId OldestXmin;
BlockNumber root_blkno = InvalidBlockNumber;
OffsetNumber root_offsets[MaxHeapTuplesPerPage];
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
/* Remember if it's a system catalog */
is_system_catalog = IsSystemRelation(heapRelation);
/* See whether we're verifying uniqueness/exclusion properties */
checking_uniqueness = (indexInfo->ii_Unique ||
indexInfo->ii_ExclusionOps != NULL);
/*
2005-10-15 04:49:52 +02:00
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = MakeSingleTupleTableSlot(RelationGetDescr(heapRelation));
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = (List *)
ExecPrepareExpr((Expr *) indexInfo->ii_Predicate,
estate);
/*
2006-10-04 02:30:14 +02:00
* Prepare for scan of the base relation. In a normal index build, we use
* SnapshotAny because we must retrieve all tuples and do our own time
* qual checks (because we have to index RECENTLY_DEAD tuples). In a
* concurrent build, we take a regular MVCC snapshot and index whatever's
* live according to that. During bootstrap we just use SnapshotNow.
*/
if (IsBootstrapProcessingMode())
{
snapshot = SnapshotNow;
2006-10-04 02:30:14 +02:00
OldestXmin = InvalidTransactionId; /* not used */
}
else if (indexInfo->ii_Concurrent)
{
snapshot = RegisterSnapshot(GetTransactionSnapshot());
2006-10-04 02:30:14 +02:00
OldestXmin = InvalidTransactionId; /* not used */
}
else
{
snapshot = SnapshotAny;
/* okay to ignore lazy VACUUMs here */
OldestXmin = GetOldestXmin(heapRelation->rd_rel->relisshared, true);
}
scan = heap_beginscan_strat(heapRelation, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
allow_sync); /* syncscan OK? */
reltuples = 0;
/*
* Scan all tuples in the base relation.
*/
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
bool tupleIsAlive;
CHECK_FOR_INTERRUPTS();
/*
2007-11-15 22:14:46 +01:00
* When dealing with a HOT-chain of updated tuples, we want to index
* the values of the live tuple (if any), but index it under the TID
* of the chain's root tuple. This approach is necessary to preserve
* the HOT-chain structure in the heap. So we need to be able to find
* the root item offset for every tuple that's in a HOT-chain. When
* first reaching a new page of the relation, call
* heap_get_root_tuples() to build a map of root item offsets on the
* page.
*
* It might look unsafe to use this information across buffer
* lock/unlock. However, we hold ShareLock on the table so no
2007-11-15 22:14:46 +01:00
* ordinary insert/update/delete should occur; and we hold pin on the
* buffer continuously while visiting the page, so no pruning
* operation can occur either.
*
* Also, although our opinions about tuple liveness could change while
* we scan the page (due to concurrent transaction commits/aborts),
* the chain root locations won't, so this info doesn't need to be
* rebuilt after waiting for another transaction.
*
* Note the implied assumption that there is no more than one live
* tuple per HOT-chain --- else we could create more than one index
* entry pointing to the same root tuple.
*/
if (scan->rs_cblock != root_blkno)
{
2007-11-15 22:14:46 +01:00
Page page = BufferGetPage(scan->rs_cbuf);
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE);
heap_get_root_tuples(page, root_offsets);
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
root_blkno = scan->rs_cblock;
}
if (snapshot == SnapshotAny)
{
/* do our own time qual check */
bool indexIt;
TransactionId xwait;
2007-11-15 22:14:46 +01:00
recheck:
/*
* We could possibly get away with not locking the buffer here,
* since caller should hold ShareLock on the relation, but let's
2007-11-15 22:14:46 +01:00
* be conservative about it. (This remark is still correct even
* with HOT-pruning: our pin on the buffer prevents pruning.)
*/
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE);
2001-03-22 05:01:46 +01:00
switch (HeapTupleSatisfiesVacuum(heapTuple->t_data, OldestXmin,
scan->rs_cbuf))
{
case HEAPTUPLE_DEAD:
/* Definitely dead, we can ignore it */
indexIt = false;
tupleIsAlive = false;
break;
case HEAPTUPLE_LIVE:
/* Normal case, index and unique-check it */
indexIt = true;
tupleIsAlive = true;
break;
case HEAPTUPLE_RECENTLY_DEAD:
/*
* If tuple is recently deleted then we must index it
* anyway to preserve MVCC semantics. (Pre-existing
2006-10-04 02:30:14 +02:00
* transactions could try to use the index after we finish
* building it, and may need to see such tuples.)
*
* However, if it was HOT-updated then we must only index
2007-11-15 22:14:46 +01:00
* the live tuple at the end of the HOT-chain. Since this
* breaks semantics for pre-existing snapshots, mark the
* index as unusable for them.
*/
if (HeapTupleIsHotUpdated(heapTuple))
{
indexIt = false;
/* mark the index as unsafe for old snapshots */
indexInfo->ii_BrokenHotChain = true;
}
else
indexIt = true;
/* In any case, exclude the tuple from unique-checking */
tupleIsAlive = false;
break;
case HEAPTUPLE_INSERT_IN_PROGRESS:
/*
* Since caller should hold ShareLock or better, normally
* the only way to see this is if it was inserted earlier
2010-02-26 03:01:40 +01:00
* in our own transaction. However, it can happen in
* system catalogs, since we tend to release write lock
* before commit there. Give a warning if neither case
* applies.
*/
xwait = HeapTupleHeaderGetXmin(heapTuple->t_data);
if (!TransactionIdIsCurrentTransactionId(xwait))
{
if (!is_system_catalog)
elog(WARNING, "concurrent insert in progress within table \"%s\"",
RelationGetRelationName(heapRelation));
/*
* If we are performing uniqueness checks, indexing
* such a tuple could lead to a bogus uniqueness
* failure. In that case we wait for the inserting
* transaction to finish and check again.
*/
if (checking_uniqueness)
{
/*
* Must drop the lock on the buffer before we wait
*/
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
goto recheck;
}
}
2007-11-15 22:14:46 +01:00
/*
* We must index such tuples, since if the index build
* commits then they're good.
*/
indexIt = true;
tupleIsAlive = true;
break;
case HEAPTUPLE_DELETE_IN_PROGRESS:
/*
* As with INSERT_IN_PROGRESS case, this is unexpected
* unless it's our own deletion or a system catalog.
*/
Assert(!(heapTuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI));
xwait = HeapTupleHeaderGetXmax(heapTuple->t_data);
if (!TransactionIdIsCurrentTransactionId(xwait))
{
if (!is_system_catalog)
elog(WARNING, "concurrent delete in progress within table \"%s\"",
RelationGetRelationName(heapRelation));
/*
* If we are performing uniqueness checks, assuming
2010-02-26 03:01:40 +01:00
* the tuple is dead could lead to missing a
* uniqueness violation. In that case we wait for the
* deleting transaction to finish and check again.
*
* Also, if it's a HOT-updated tuple, we should not
* index it but rather the live tuple at the end of
* the HOT-chain. However, the deleting transaction
* could abort, possibly leaving this tuple as live
* after all, in which case it has to be indexed. The
* only way to know what to do is to wait for the
* deleting transaction to finish and check again.
*/
if (checking_uniqueness ||
HeapTupleIsHotUpdated(heapTuple))
{
/*
* Must drop the lock on the buffer before we wait
*/
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
XactLockTableWait(xwait);
goto recheck;
}
2007-11-15 22:14:46 +01:00
/*
* Otherwise index it but don't check for uniqueness,
* the same as a RECENTLY_DEAD tuple.
*/
indexIt = true;
}
else if (HeapTupleIsHotUpdated(heapTuple))
{
/*
* It's a HOT-updated tuple deleted by our own xact.
* We can assume the deletion will commit (else the
* index contents don't matter), so treat the same
* as RECENTLY_DEAD HOT-updated tuples.
*/
indexIt = false;
/* mark the index as unsafe for old snapshots */
indexInfo->ii_BrokenHotChain = true;
}
else
{
/*
* It's a regular tuple deleted by our own xact.
* Index it but don't check for uniqueness, the same
* as a RECENTLY_DEAD tuple.
*/
indexIt = true;
}
/* In any case, exclude the tuple from unique-checking */
tupleIsAlive = false;
break;
default:
elog(ERROR, "unexpected HeapTupleSatisfiesVacuum result");
2007-11-15 22:14:46 +01:00
indexIt = tupleIsAlive = false; /* keep compiler quiet */
break;
}
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
if (!indexIt)
continue;
}
else
{
/* heap_getnext did the time qual check */
tupleIsAlive = true;
}
reltuples += 1;
MemoryContextReset(econtext->ecxt_per_tuple_memory);
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/* Set up for predicate or expression evaluation */
ExecStoreTuple(heapTuple, slot, InvalidBuffer, false);
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/*
* In a partial index, discard tuples that don't satisfy the
* predicate.
*/
if (predicate != NIL)
{
if (!ExecQual(predicate, econtext, false))
continue;
}
/*
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* For the current heap tuple, extract all the attributes we use in
* this index, and note which are null. This also performs evaluation
* of any expressions needed.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
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* You'd think we should go ahead and build the index tuple here, but
* some index AMs want to do further processing on the data first. So
* pass the values[] and isnull[] arrays, instead.
*/
if (HeapTupleIsHeapOnly(heapTuple))
{
/*
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* For a heap-only tuple, pretend its TID is that of the root. See
* src/backend/access/heap/README.HOT for discussion.
*/
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HeapTupleData rootTuple;
OffsetNumber offnum;
rootTuple = *heapTuple;
offnum = ItemPointerGetOffsetNumber(&heapTuple->t_self);
Assert(OffsetNumberIsValid(root_offsets[offnum - 1]));
ItemPointerSetOffsetNumber(&rootTuple.t_self,
root_offsets[offnum - 1]);
/* Call the AM's callback routine to process the tuple */
callback(indexRelation, &rootTuple, values, isnull, tupleIsAlive,
callback_state);
}
else
{
/* Call the AM's callback routine to process the tuple */
callback(indexRelation, heapTuple, values, isnull, tupleIsAlive,
callback_state);
}
}
heap_endscan(scan);
/* we can now forget our snapshot, if set */
if (indexInfo->ii_Concurrent)
UnregisterSnapshot(snapshot);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NIL;
return reltuples;
}
/*
* IndexCheckExclusion - verify that a new exclusion constraint is satisfied
*
* When creating an exclusion constraint, we first build the index normally
* and then rescan the heap to check for conflicts. We assume that we only
* need to validate tuples that are live according to SnapshotNow, and that
* these were correctly indexed even in the presence of broken HOT chains.
* This should be OK since we are holding at least ShareLock on the table,
* meaning there can be no uncommitted updates from other transactions.
* (Note: that wouldn't necessarily work for system catalogs, since many
* operations release write lock early on the system catalogs.)
*/
static void
IndexCheckExclusion(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo)
{
HeapScanDesc scan;
HeapTuple heapTuple;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
List *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
/*
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = MakeSingleTupleTableSlot(RelationGetDescr(heapRelation));
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = (List *)
ExecPrepareExpr((Expr *) indexInfo->ii_Predicate,
estate);
/*
* Scan all live tuples in the base relation.
*/
scan = heap_beginscan_strat(heapRelation, /* relation */
SnapshotNow, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
true); /* syncscan OK */
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
CHECK_FOR_INTERRUPTS();
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/* Set up for predicate or expression evaluation */
ExecStoreTuple(heapTuple, slot, InvalidBuffer, false);
/*
* In a partial index, ignore tuples that don't satisfy the predicate.
*/
if (predicate != NIL)
{
if (!ExecQual(predicate, econtext, false))
continue;
}
/*
* Extract index column values, including computing expressions.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
* Check that this tuple has no conflicts.
*/
check_exclusion_constraint(heapRelation,
indexRelation, indexInfo,
&(heapTuple->t_self), values, isnull,
estate, true, false);
}
heap_endscan(scan);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NIL;
}
/*
* validate_index - support code for concurrent index builds
*
* We do a concurrent index build by first inserting the catalog entry for the
* index via index_create(), marking it not indisready and not indisvalid.
* Then we commit our transaction and start a new one, then we wait for all
2007-11-15 22:14:46 +01:00
* transactions that could have been modifying the table to terminate. Now
* we know that any subsequently-started transactions will see the index and
* honor its constraints on HOT updates; so while existing HOT-chains might
* be broken with respect to the index, no currently live tuple will have an
2007-11-15 22:14:46 +01:00
* incompatible HOT update done to it. We now build the index normally via
* index_build(), while holding a weak lock that allows concurrent
* insert/update/delete. Also, we index only tuples that are valid
* as of the start of the scan (see IndexBuildHeapScan), whereas a normal
* build takes care to include recently-dead tuples. This is OK because
* we won't mark the index valid until all transactions that might be able
* to see those tuples are gone. The reason for doing that is to avoid
* bogus unique-index failures due to concurrent UPDATEs (we might see
* different versions of the same row as being valid when we pass over them,
* if we used HeapTupleSatisfiesVacuum). This leaves us with an index that
* does not contain any tuples added to the table while we built the index.
*
* Next, we mark the index "indisready" (but still not "indisvalid") and
* commit the second transaction and start a third. Again we wait for all
2007-11-15 22:14:46 +01:00
* transactions that could have been modifying the table to terminate. Now
* we know that any subsequently-started transactions will see the index and
* insert their new tuples into it. We then take a new reference snapshot
* which is passed to validate_index(). Any tuples that are valid according
* to this snap, but are not in the index, must be added to the index.
* (Any tuples committed live after the snap will be inserted into the
2006-10-04 02:30:14 +02:00
* index by their originating transaction. Any tuples committed dead before
* the snap need not be indexed, because we will wait out all transactions
* that might care about them before we mark the index valid.)
*
* validate_index() works by first gathering all the TIDs currently in the
* index, using a bulkdelete callback that just stores the TIDs and doesn't
* ever say "delete it". (This should be faster than a plain indexscan;
* also, not all index AMs support full-index indexscan.) Then we sort the
* TIDs, and finally scan the table doing a "merge join" against the TID list
2006-10-04 02:30:14 +02:00
* to see which tuples are missing from the index. Thus we will ensure that
* all tuples valid according to the reference snapshot are in the index.
*
* Building a unique index this way is tricky: we might try to insert a
* tuple that is already dead or is in process of being deleted, and we
* mustn't have a uniqueness failure against an updated version of the same
* row. We could try to check the tuple to see if it's already dead and tell
* index_insert() not to do the uniqueness check, but that still leaves us
* with a race condition against an in-progress update. To handle that,
* we expect the index AM to recheck liveness of the to-be-inserted tuple
* before it declares a uniqueness error.
*
* After completing validate_index(), we wait until all transactions that
* were alive at the time of the reference snapshot are gone; this is
* necessary to be sure there are none left with a transaction snapshot
* older than the reference (and hence possibly able to see tuples we did
* not index). Then we mark the index "indisvalid" and commit. Subsequent
* transactions will be able to use it for queries.
*
* Doing two full table scans is a brute-force strategy. We could try to be
* cleverer, eg storing new tuples in a special area of the table (perhaps
* making the table append-only by setting use_fsm). However that would
* add yet more locking issues.
*/
void
validate_index(Oid heapId, Oid indexId, Snapshot snapshot)
{
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Relation heapRelation,
indexRelation;
IndexInfo *indexInfo;
IndexVacuumInfo ivinfo;
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v_i_state state;
Oid save_userid;
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int save_sec_context;
int save_nestlevel;
/* Open and lock the parent heap relation */
heapRelation = heap_open(heapId, ShareUpdateExclusiveLock);
/* And the target index relation */
indexRelation = index_open(indexId, RowExclusiveLock);
/*
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* Fetch info needed for index_insert. (You might think this should be
* passed in from DefineIndex, but its copy is long gone due to having
* been built in a previous transaction.)
*/
indexInfo = BuildIndexInfo(indexRelation);
/* mark build is concurrent just for consistency */
indexInfo->ii_Concurrent = true;
/*
* Switch to the table owner's userid, so that any index functions are run
2009-12-09 22:57:51 +01:00
* as that user. Also lock down security-restricted operations and
* arrange to make GUC variable changes local to this command.
*/
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GetUserIdAndSecContext(&save_userid, &save_sec_context);
SetUserIdAndSecContext(heapRelation->rd_rel->relowner,
save_sec_context | SECURITY_RESTRICTED_OPERATION);
save_nestlevel = NewGUCNestLevel();
/*
* Scan the index and gather up all the TIDs into a tuplesort object.
*/
ivinfo.index = indexRelation;
ivinfo.analyze_only = false;
ivinfo.estimated_count = true;
ivinfo.message_level = DEBUG2;
ivinfo.num_heap_tuples = heapRelation->rd_rel->reltuples;
ivinfo.strategy = NULL;
state.tuplesort = tuplesort_begin_datum(TIDOID, TIDLessOperator,
InvalidOid, false,
maintenance_work_mem,
false);
state.htups = state.itups = state.tups_inserted = 0;
(void) index_bulk_delete(&ivinfo, NULL,
validate_index_callback, (void *) &state);
/* Execute the sort */
tuplesort_performsort(state.tuplesort);
/*
* Now scan the heap and "merge" it with the index
*/
validate_index_heapscan(heapRelation,
indexRelation,
indexInfo,
snapshot,
&state);
/* Done with tuplesort object */
tuplesort_end(state.tuplesort);
elog(DEBUG2,
"validate_index found %.0f heap tuples, %.0f index tuples; inserted %.0f missing tuples",
state.htups, state.itups, state.tups_inserted);
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/* Roll back any GUC changes executed by index functions */
AtEOXact_GUC(false, save_nestlevel);
/* Restore userid and security context */
SetUserIdAndSecContext(save_userid, save_sec_context);
/* Close rels, but keep locks */
index_close(indexRelation, NoLock);
heap_close(heapRelation, NoLock);
}
/*
* validate_index_callback - bulkdelete callback to collect the index TIDs
*/
static bool
validate_index_callback(ItemPointer itemptr, void *opaque)
{
2006-10-04 02:30:14 +02:00
v_i_state *state = (v_i_state *) opaque;
tuplesort_putdatum(state->tuplesort, PointerGetDatum(itemptr), false);
state->itups += 1;
return false; /* never actually delete anything */
}
/*
* validate_index_heapscan - second table scan for concurrent index build
*
* This has much code in common with IndexBuildHeapScan, but it's enough
* different that it seems cleaner to have two routines not one.
*/
static void
validate_index_heapscan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
Snapshot snapshot,
v_i_state *state)
{
HeapScanDesc scan;
HeapTuple heapTuple;
Datum values[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
List *predicate;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
BlockNumber root_blkno = InvalidBlockNumber;
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OffsetNumber root_offsets[MaxHeapTuplesPerPage];
bool in_index[MaxHeapTuplesPerPage];
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/* state variables for the merge */
ItemPointer indexcursor = NULL;
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bool tuplesort_empty = false;
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
/*
* Need an EState for evaluation of index expressions and partial-index
* predicates. Also a slot to hold the current tuple.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
slot = MakeSingleTupleTableSlot(RelationGetDescr(heapRelation));
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate, if any. */
predicate = (List *)
ExecPrepareExpr((Expr *) indexInfo->ii_Predicate,
estate);
/*
* Prepare for scan of the base relation. We need just those tuples
* satisfying the passed-in reference snapshot. We must disable syncscan
* here, because it's critical that we read from block zero forward to
* match the sorted TIDs.
*/
scan = heap_beginscan_strat(heapRelation, /* relation */
snapshot, /* snapshot */
0, /* number of keys */
NULL, /* scan key */
true, /* buffer access strategy OK */
false); /* syncscan not OK */
/*
* Scan all tuples matching the snapshot.
*/
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
ItemPointer heapcursor = &heapTuple->t_self;
ItemPointerData rootTuple;
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OffsetNumber root_offnum;
CHECK_FOR_INTERRUPTS();
state->htups += 1;
/*
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* As commented in IndexBuildHeapScan, we should index heap-only
* tuples under the TIDs of their root tuples; so when we advance onto
* a new heap page, build a map of root item offsets on the page.
*
* This complicates merging against the tuplesort output: we will
* visit the live tuples in order by their offsets, but the root
2007-11-15 22:14:46 +01:00
* offsets that we need to compare against the index contents might be
* ordered differently. So we might have to "look back" within the
* tuplesort output, but only within the current page. We handle that
* by keeping a bool array in_index[] showing all the
* already-passed-over tuplesort output TIDs of the current page. We
* clear that array here, when advancing onto a new heap page.
*/
if (scan->rs_cblock != root_blkno)
{
2007-11-15 22:14:46 +01:00
Page page = BufferGetPage(scan->rs_cbuf);
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE);
heap_get_root_tuples(page, root_offsets);
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
memset(in_index, 0, sizeof(in_index));
root_blkno = scan->rs_cblock;
}
/* Convert actual tuple TID to root TID */
rootTuple = *heapcursor;
root_offnum = ItemPointerGetOffsetNumber(heapcursor);
if (HeapTupleIsHeapOnly(heapTuple))
{
root_offnum = root_offsets[root_offnum - 1];
Assert(OffsetNumberIsValid(root_offnum));
ItemPointerSetOffsetNumber(&rootTuple, root_offnum);
}
/*
2006-10-04 02:30:14 +02:00
* "merge" by skipping through the index tuples until we find or pass
* the current root tuple.
*/
while (!tuplesort_empty &&
(!indexcursor ||
ItemPointerCompare(indexcursor, &rootTuple) < 0))
{
2006-10-04 02:30:14 +02:00
Datum ts_val;
bool ts_isnull;
if (indexcursor)
{
/*
* Remember index items seen earlier on the current heap page
*/
if (ItemPointerGetBlockNumber(indexcursor) == root_blkno)
in_index[ItemPointerGetOffsetNumber(indexcursor) - 1] = true;
pfree(indexcursor);
}
tuplesort_empty = !tuplesort_getdatum(state->tuplesort, true,
&ts_val, &ts_isnull);
Assert(tuplesort_empty || !ts_isnull);
indexcursor = (ItemPointer) DatumGetPointer(ts_val);
}
/*
* If the tuplesort has overshot *and* we didn't see a match earlier,
* then this tuple is missing from the index, so insert it.
*/
if ((tuplesort_empty ||
ItemPointerCompare(indexcursor, &rootTuple) > 0) &&
!in_index[root_offnum - 1])
{
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/* Set up for predicate or expression evaluation */
ExecStoreTuple(heapTuple, slot, InvalidBuffer, false);
/*
* In a partial index, discard tuples that don't satisfy the
* predicate.
*/
if (predicate != NIL)
{
if (!ExecQual(predicate, econtext, false))
continue;
}
/*
* For the current heap tuple, extract all the attributes we use
2006-10-04 02:30:14 +02:00
* in this index, and note which are null. This also performs
* evaluation of any expressions needed.
*/
FormIndexDatum(indexInfo,
slot,
estate,
values,
isnull);
/*
* You'd think we should go ahead and build the index tuple here,
* but some index AMs want to do further processing on the data
* first. So pass the values[] and isnull[] arrays, instead.
*/
/*
* If the tuple is already committed dead, you might think we
2007-11-15 22:14:46 +01:00
* could suppress uniqueness checking, but this is no longer true
* in the presence of HOT, because the insert is actually a proxy
* for a uniqueness check on the whole HOT-chain. That is, the
* tuple we have here could be dead because it was already
* HOT-updated, and if so the updating transaction will not have
2007-11-15 22:14:46 +01:00
* thought it should insert index entries. The index AM will
* check the whole HOT-chain and correctly detect a conflict if
* there is one.
*/
index_insert(indexRelation,
values,
isnull,
&rootTuple,
heapRelation,
indexInfo->ii_Unique ?
UNIQUE_CHECK_YES : UNIQUE_CHECK_NO);
state->tups_inserted += 1;
}
}
heap_endscan(scan);
ExecDropSingleTupleTableSlot(slot);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NIL;
}
/*
* IndexGetRelation: given an index's relation OID, get the OID of the
* relation it is an index on. Uses the system cache.
*/
static Oid
IndexGetRelation(Oid indexId)
{
HeapTuple tuple;
Form_pg_index index;
Oid result;
tuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexId));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for index %u", indexId);
index = (Form_pg_index) GETSTRUCT(tuple);
Assert(index->indexrelid == indexId);
result = index->indrelid;
ReleaseSysCache(tuple);
return result;
}
/*
* reindex_index - This routine is used to recreate a single index
2000-02-18 10:30:20 +01:00
*/
void
reindex_index(Oid indexId, bool skip_constraint_checks)
2000-02-18 10:30:20 +01:00
{
Relation iRel,
heapRelation,
pg_index;
Oid heapId;
IndexInfo *indexInfo;
HeapTuple indexTuple;
Form_pg_index indexForm;
volatile bool skipped_constraint = false;
2000-02-18 10:30:20 +01:00
/*
2005-10-15 04:49:52 +02:00
* Open and lock the parent heap relation. ShareLock is sufficient since
* we only need to be sure no schema or data changes are going on.
*/
heapId = IndexGetRelation(indexId);
heapRelation = heap_open(heapId, ShareLock);
/*
2005-10-15 04:49:52 +02:00
* Open the target index relation and get an exclusive lock on it, to
* ensure that no one else is touching this particular index.
*/
iRel = index_open(indexId, AccessExclusiveLock);
/*
* Don't allow reindex on temp tables of other backends ... their local
* buffer manager is not going to cope.
*/
if (RELATION_IS_OTHER_TEMP(iRel))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot reindex temporary tables of other sessions")));
/*
* Also check for active uses of the index in the current transaction; we
* don't want to reindex underneath an open indexscan.
*/
CheckTableNotInUse(iRel, "REINDEX INDEX");
PG_TRY();
2000-12-08 07:17:58 +01:00
{
/* Suppress use of the target index while rebuilding it */
SetReindexProcessing(heapId, indexId);
/* Fetch info needed for index_build */
indexInfo = BuildIndexInfo(iRel);
/* If requested, skip checking uniqueness/exclusion constraints */
if (skip_constraint_checks)
{
if (indexInfo->ii_Unique || indexInfo->ii_ExclusionOps != NULL)
skipped_constraint = true;
indexInfo->ii_Unique = false;
indexInfo->ii_ExclusionOps = NULL;
indexInfo->ii_ExclusionProcs = NULL;
indexInfo->ii_ExclusionStrats = NULL;
}
/* We'll build a new physical relation for the index */
RelationSetNewRelfilenode(iRel, InvalidTransactionId);
/* Initialize the index and rebuild */
/* Note: we do not need to re-establish pkey setting */
index_build(heapRelation, iRel, indexInfo, false, true);
2000-12-08 07:17:58 +01:00
}
PG_CATCH();
{
/* Make sure flag gets cleared on error exit */
ResetReindexProcessing();
PG_RE_THROW();
}
PG_END_TRY();
ResetReindexProcessing();
/*
* If the index is marked invalid or not ready (ie, it's from a failed
2010-02-26 03:01:40 +01:00
* CREATE INDEX CONCURRENTLY), and we didn't skip a uniqueness check, we
* can now mark it valid. This allows REINDEX to be used to clean up in
* such cases.
*
* We can also reset indcheckxmin, because we have now done a
* non-concurrent index build, *except* in the case where index_build
* found some still-broken HOT chains. If it did, we normally leave
* indcheckxmin alone (note that index_build won't have changed it,
* because this is a reindex). But if the index was invalid or not ready
* and there were broken HOT chains, it seems best to force indcheckxmin
* true, because the normal argument that the HOT chains couldn't conflict
* with the index is suspect for an invalid index.
*
* Note that it is important to not update the pg_index entry if we don't
* have to, because updating it will move the index's usability horizon
* (recorded as the tuple's xmin value) if indcheckxmin is true. We don't
* really want REINDEX to move the usability horizon forward ever, but we
* have no choice if we are to fix indisvalid or indisready. Of course,
* clearing indcheckxmin eliminates the issue, so we're happy to do that
* if we can. Another reason for caution here is that while reindexing
* pg_index itself, we must not try to update it. We assume that
* pg_index's indexes will always have these flags in their clean state.
*/
if (!skipped_constraint)
{
pg_index = heap_open(IndexRelationId, RowExclusiveLock);
indexTuple = SearchSysCacheCopy1(INDEXRELID,
ObjectIdGetDatum(indexId));
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "cache lookup failed for index %u", indexId);
indexForm = (Form_pg_index) GETSTRUCT(indexTuple);
if (!indexForm->indisvalid || !indexForm->indisready ||
(indexForm->indcheckxmin && !indexInfo->ii_BrokenHotChain))
{
if (!indexInfo->ii_BrokenHotChain)
indexForm->indcheckxmin = false;
else if (!indexForm->indisvalid || !indexForm->indisready)
indexForm->indcheckxmin = true;
indexForm->indisvalid = true;
indexForm->indisready = true;
simple_heap_update(pg_index, &indexTuple->t_self, indexTuple);
CatalogUpdateIndexes(pg_index, indexTuple);
}
heap_close(pg_index, RowExclusiveLock);
}
/* Close rels, but keep locks */
index_close(iRel, NoLock);
heap_close(heapRelation, NoLock);
2000-02-18 10:30:20 +01:00
}
/*
* reindex_relation - This routine is used to recreate all indexes
* of a relation (and optionally its toast relation too, if any).
*
* "flags" is a bitmask that can include any combination of these bits:
*
* REINDEX_REL_PROCESS_TOAST: if true, process the toast table too (if any).
*
* REINDEX_REL_SUPPRESS_INDEX_USE: if true, the relation was just completely
* rebuilt by an operation such as VACUUM FULL or CLUSTER, and therefore its
* indexes are inconsistent with it. This makes things tricky if the relation
* is a system catalog that we might consult during the reindexing. To deal
* with that case, we mark all of the indexes as pending rebuild so that they
* won't be trusted until rebuilt. The caller is required to call us *without*
* having made the rebuilt table visible by doing CommandCounterIncrement;
* we'll do CCI after having collected the index list. (This way we can still
* use catalog indexes while collecting the list.)
*
* REINDEX_REL_CHECK_CONSTRAINTS: if true, recheck unique and exclusion
* constraint conditions, else don't. To avoid deadlocks, VACUUM FULL or
* CLUSTER on a system catalog must omit this flag. REINDEX should be used to
* rebuild an index if constraint inconsistency is suspected. For optimal
* performance, other callers should include the flag only after transforming
* the data in a manner that risks a change in constraint validity.
*
* Returns true if any indexes were rebuilt (including toast table's index
* when relevant). Note that a CommandCounterIncrement will occur after each
* index rebuild.
2000-02-18 10:30:20 +01:00
*/
bool
reindex_relation(Oid relid, int flags)
2000-02-18 10:30:20 +01:00
{
2001-03-22 05:01:46 +01:00
Relation rel;
Oid toast_relid;
List *indexIds;
bool is_pg_class;
bool result;
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/*
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* Open and lock the relation. ShareLock is sufficient since we only need
* to prevent schema and data changes in it.
*/
rel = heap_open(relid, ShareLock);
toast_relid = rel->rd_rel->reltoastrelid;
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/*
* Get the list of index OIDs for this relation. (We trust to the
* relcache to get this with a sequential scan if ignoring system
* indexes.)
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*/
indexIds = RelationGetIndexList(rel);
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/*
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* reindex_index will attempt to update the pg_class rows for the relation
* and index. If we are processing pg_class itself, we want to make sure
* that the updates do not try to insert index entries into indexes we
* have not processed yet. (When we are trying to recover from corrupted
* indexes, that could easily cause a crash.) We can accomplish this
* because CatalogUpdateIndexes will use the relcache's index list to know
* which indexes to update. We just force the index list to be only the
* stuff we've processed.
*
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* It is okay to not insert entries into the indexes we have not processed
* yet because all of this is transaction-safe. If we fail partway
* through, the updated rows are dead and it doesn't matter whether they
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* have index entries. Also, a new pg_class index will be created with a
* correct entry for its own pg_class row because we do
* RelationSetNewRelfilenode() before we do index_build().
*
* Note that we also clear pg_class's rd_oidindex until the loop is done,
* so that that index can't be accessed either. This means we cannot
* safely generate new relation OIDs while in the loop; shouldn't be a
* problem.
*/
is_pg_class = (RelationGetRelid(rel) == RelationRelationId);
/* Ensure rd_indexattr is valid; see comments for RelationSetIndexList */
if (is_pg_class)
(void) RelationGetIndexAttrBitmap(rel);
PG_TRY();
{
List *doneIndexes;
ListCell *indexId;
if (flags & REINDEX_REL_SUPPRESS_INDEX_USE)
{
/* Suppress use of all the indexes until they are rebuilt */
SetReindexPending(indexIds);
/*
* Make the new heap contents visible --- now things might be
* inconsistent!
*/
CommandCounterIncrement();
}
/* Reindex all the indexes. */
doneIndexes = NIL;
foreach(indexId, indexIds)
{
Oid indexOid = lfirst_oid(indexId);
if (is_pg_class)
RelationSetIndexList(rel, doneIndexes, InvalidOid);
reindex_index(indexOid, !(flags & REINDEX_REL_CHECK_CONSTRAINTS));
CommandCounterIncrement();
if (flags & REINDEX_REL_SUPPRESS_INDEX_USE)
RemoveReindexPending(indexOid);
if (is_pg_class)
doneIndexes = lappend_oid(doneIndexes, indexOid);
}
}
PG_CATCH();
{
/* Make sure list gets cleared on error exit */
ResetReindexPending();
PG_RE_THROW();
}
PG_END_TRY();
ResetReindexPending();
if (is_pg_class)
RelationSetIndexList(rel, indexIds, ClassOidIndexId);
/*
* Close rel, but continue to hold the lock.
*/
heap_close(rel, NoLock);
result = (indexIds != NIL);
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/*
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* If the relation has a secondary toast rel, reindex that too while we
* still hold the lock on the master table.
*/
if ((flags & REINDEX_REL_PROCESS_TOAST) && OidIsValid(toast_relid))
result |= reindex_relation(toast_relid, flags);
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return result;
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}
/* ----------------------------------------------------------------
* System index reindexing support
*
* When we are busy reindexing a system index, this code provides support
* for preventing catalog lookups from using that index.
* ----------------------------------------------------------------
*/
static Oid currentlyReindexedHeap = InvalidOid;
static Oid currentlyReindexedIndex = InvalidOid;
static List *pendingReindexedIndexes = NIL;
/*
* ReindexIsProcessingHeap
* True if heap specified by OID is currently being reindexed.
*/
bool
ReindexIsProcessingHeap(Oid heapOid)
{
return heapOid == currentlyReindexedHeap;
}
/*
* ReindexIsProcessingIndex
* True if index specified by OID is currently being reindexed,
* or should be treated as invalid because it is awaiting reindex.
*/
bool
ReindexIsProcessingIndex(Oid indexOid)
{
return indexOid == currentlyReindexedIndex ||
list_member_oid(pendingReindexedIndexes, indexOid);
}
/*
* SetReindexProcessing
* Set flag that specified heap/index are being reindexed.
*
* NB: caller must use a PG_TRY block to ensure ResetReindexProcessing is done.
*/
static void
SetReindexProcessing(Oid heapOid, Oid indexOid)
{
Assert(OidIsValid(heapOid) && OidIsValid(indexOid));
/* Reindexing is not re-entrant. */
if (OidIsValid(currentlyReindexedHeap))
elog(ERROR, "cannot reindex while reindexing");
currentlyReindexedHeap = heapOid;
currentlyReindexedIndex = indexOid;
}
/*
* ResetReindexProcessing
* Unset reindexing status.
*/
static void
ResetReindexProcessing(void)
{
currentlyReindexedHeap = InvalidOid;
currentlyReindexedIndex = InvalidOid;
}
/*
* SetReindexPending
* Mark the given indexes as pending reindex.
*
* NB: caller must use a PG_TRY block to ensure ResetReindexPending is done.
* Also, we assume that the current memory context stays valid throughout.
*/
static void
SetReindexPending(List *indexes)
{
/* Reindexing is not re-entrant. */
if (pendingReindexedIndexes)
elog(ERROR, "cannot reindex while reindexing");
pendingReindexedIndexes = list_copy(indexes);
}
/*
* RemoveReindexPending
* Remove the given index from the pending list.
*/
static void
RemoveReindexPending(Oid indexOid)
{
pendingReindexedIndexes = list_delete_oid(pendingReindexedIndexes,
indexOid);
}
/*
* ResetReindexPending
* Unset reindex-pending status.
*/
static void
ResetReindexPending(void)
{
pendingReindexedIndexes = NIL;
}