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Currently adding a column to a table with a non-NULL default results in a rewrite of the table. For large tables this can be both expensive and disruptive. This patch removes the need for the rewrite as long as the default value is not volatile. The default expression is evaluated at the time of the ALTER TABLE and the result stored in a new column (attmissingval) in pg_attribute, and a new column (atthasmissing) is set to true. Any existing row when fetched will be supplied with the attmissingval. New rows will have the supplied value or the default and so will never need the attmissingval. Any time the table is rewritten all the atthasmissing and attmissingval settings for the attributes are cleared, as they are no longer needed. The most visible code change from this is in heap_attisnull, which acquires a third TupleDesc argument, allowing it to detect a missing value if there is one. In many cases where it is known that there will not be any (e.g. catalog relations) NULL can be passed for this argument. Andrew Dunstan, heavily modified from an original patch from Serge Rielau. Reviewed by Tom Lane, Andres Freund, Tomas Vondra and David Rowley. Discussion: https://postgr.es/m/31e2e921-7002-4c27-59f5-51f08404c858@2ndQuadrant.com
3240 lines
90 KiB
C
3240 lines
90 KiB
C
/* ----------
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* ri_triggers.c
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*
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* Generic trigger procedures for referential integrity constraint
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* checks.
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*
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* Note about memory management: the private hashtables kept here live
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* across query and transaction boundaries, in fact they live as long as
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* the backend does. This works because the hashtable structures
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* themselves are allocated by dynahash.c in its permanent DynaHashCxt,
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* and the SPI plans they point to are saved using SPI_keepplan().
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* There is not currently any provision for throwing away a no-longer-needed
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* plan --- consider improving this someday.
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*
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*
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* Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
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*
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* src/backend/utils/adt/ri_triggers.c
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*
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* ----------
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*/
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/* ----------
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* Internal TODO:
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*
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* Add MATCH PARTIAL logic.
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* ----------
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*/
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#include "postgres.h"
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#include "access/htup_details.h"
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#include "access/sysattr.h"
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#include "access/xact.h"
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#include "catalog/pg_collation.h"
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#include "catalog/pg_constraint.h"
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#include "catalog/pg_operator.h"
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#include "catalog/pg_type.h"
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#include "commands/trigger.h"
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#include "executor/executor.h"
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#include "executor/spi.h"
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#include "lib/ilist.h"
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#include "parser/parse_coerce.h"
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#include "parser/parse_relation.h"
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#include "miscadmin.h"
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#include "storage/bufmgr.h"
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#include "utils/acl.h"
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#include "utils/builtins.h"
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#include "utils/fmgroids.h"
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#include "utils/guc.h"
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#include "utils/inval.h"
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#include "utils/lsyscache.h"
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#include "utils/memutils.h"
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#include "utils/rel.h"
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#include "utils/rls.h"
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#include "utils/snapmgr.h"
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#include "utils/syscache.h"
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#include "utils/tqual.h"
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/* ----------
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* Local definitions
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* ----------
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*/
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#define RI_MAX_NUMKEYS INDEX_MAX_KEYS
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#define RI_INIT_CONSTRAINTHASHSIZE 64
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#define RI_INIT_QUERYHASHSIZE (RI_INIT_CONSTRAINTHASHSIZE * 4)
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#define RI_KEYS_ALL_NULL 0
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#define RI_KEYS_SOME_NULL 1
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#define RI_KEYS_NONE_NULL 2
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/* RI query type codes */
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/* these queries are executed against the PK (referenced) table: */
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#define RI_PLAN_CHECK_LOOKUPPK 1
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#define RI_PLAN_CHECK_LOOKUPPK_FROM_PK 2
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#define RI_PLAN_LAST_ON_PK RI_PLAN_CHECK_LOOKUPPK_FROM_PK
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/* these queries are executed against the FK (referencing) table: */
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#define RI_PLAN_CASCADE_DEL_DODELETE 3
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#define RI_PLAN_CASCADE_UPD_DOUPDATE 4
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#define RI_PLAN_RESTRICT_CHECKREF 5
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#define RI_PLAN_SETNULL_DOUPDATE 6
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#define RI_PLAN_SETDEFAULT_DOUPDATE 7
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#define MAX_QUOTED_NAME_LEN (NAMEDATALEN*2+3)
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#define MAX_QUOTED_REL_NAME_LEN (MAX_QUOTED_NAME_LEN*2)
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#define RIAttName(rel, attnum) NameStr(*attnumAttName(rel, attnum))
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#define RIAttType(rel, attnum) attnumTypeId(rel, attnum)
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#define RIAttCollation(rel, attnum) attnumCollationId(rel, attnum)
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#define RI_TRIGTYPE_INSERT 1
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#define RI_TRIGTYPE_UPDATE 2
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#define RI_TRIGTYPE_DELETE 3
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/* ----------
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* RI_ConstraintInfo
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*
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* Information extracted from an FK pg_constraint entry. This is cached in
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* ri_constraint_cache.
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* ----------
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*/
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typedef struct RI_ConstraintInfo
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{
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Oid constraint_id; /* OID of pg_constraint entry (hash key) */
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bool valid; /* successfully initialized? */
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uint32 oidHashValue; /* hash value of pg_constraint OID */
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NameData conname; /* name of the FK constraint */
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Oid pk_relid; /* referenced relation */
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Oid fk_relid; /* referencing relation */
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char confupdtype; /* foreign key's ON UPDATE action */
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char confdeltype; /* foreign key's ON DELETE action */
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char confmatchtype; /* foreign key's match type */
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int nkeys; /* number of key columns */
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int16 pk_attnums[RI_MAX_NUMKEYS]; /* attnums of referenced cols */
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int16 fk_attnums[RI_MAX_NUMKEYS]; /* attnums of referencing cols */
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Oid pf_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = FK) */
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Oid pp_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = PK) */
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Oid ff_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (FK = FK) */
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dlist_node valid_link; /* Link in list of valid entries */
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} RI_ConstraintInfo;
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/* ----------
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* RI_QueryKey
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*
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* The key identifying a prepared SPI plan in our query hashtable
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* ----------
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*/
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typedef struct RI_QueryKey
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{
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Oid constr_id; /* OID of pg_constraint entry */
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int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
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} RI_QueryKey;
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/* ----------
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* RI_QueryHashEntry
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* ----------
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*/
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typedef struct RI_QueryHashEntry
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{
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RI_QueryKey key;
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SPIPlanPtr plan;
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} RI_QueryHashEntry;
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/* ----------
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* RI_CompareKey
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*
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* The key identifying an entry showing how to compare two values
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* ----------
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*/
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typedef struct RI_CompareKey
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{
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Oid eq_opr; /* the equality operator to apply */
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Oid typeid; /* the data type to apply it to */
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} RI_CompareKey;
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/* ----------
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* RI_CompareHashEntry
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* ----------
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*/
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typedef struct RI_CompareHashEntry
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{
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RI_CompareKey key;
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bool valid; /* successfully initialized? */
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FmgrInfo eq_opr_finfo; /* call info for equality fn */
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FmgrInfo cast_func_finfo; /* in case we must coerce input */
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} RI_CompareHashEntry;
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/* ----------
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* Local data
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* ----------
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*/
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static HTAB *ri_constraint_cache = NULL;
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static HTAB *ri_query_cache = NULL;
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static HTAB *ri_compare_cache = NULL;
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static dlist_head ri_constraint_cache_valid_list;
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static int ri_constraint_cache_valid_count = 0;
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/* ----------
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* Local function prototypes
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* ----------
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*/
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static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
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HeapTuple old_row,
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const RI_ConstraintInfo *riinfo);
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static Datum ri_restrict(TriggerData *trigdata, bool is_no_action);
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static Datum ri_setnull(TriggerData *trigdata);
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static Datum ri_setdefault(TriggerData *trigdata);
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static void quoteOneName(char *buffer, const char *name);
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static void quoteRelationName(char *buffer, Relation rel);
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static void ri_GenerateQual(StringInfo buf,
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const char *sep,
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const char *leftop, Oid leftoptype,
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Oid opoid,
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const char *rightop, Oid rightoptype);
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static void ri_GenerateQualCollation(StringInfo buf, Oid collation);
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static int ri_NullCheck(TupleDesc tupdesc, HeapTuple tup,
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const RI_ConstraintInfo *riinfo, bool rel_is_pk);
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static void ri_BuildQueryKey(RI_QueryKey *key,
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const RI_ConstraintInfo *riinfo,
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int32 constr_queryno);
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static bool ri_KeysEqual(Relation rel, HeapTuple oldtup, HeapTuple newtup,
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const RI_ConstraintInfo *riinfo, bool rel_is_pk);
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static bool ri_AttributesEqual(Oid eq_opr, Oid typeid,
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Datum oldvalue, Datum newvalue);
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static void ri_InitHashTables(void);
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static void InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue);
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static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key);
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static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan);
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static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
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static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
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int tgkind);
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static const RI_ConstraintInfo *ri_FetchConstraintInfo(Trigger *trigger,
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Relation trig_rel, bool rel_is_pk);
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static const RI_ConstraintInfo *ri_LoadConstraintInfo(Oid constraintOid);
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static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
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RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel,
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bool cache_plan);
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static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo,
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RI_QueryKey *qkey, SPIPlanPtr qplan,
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Relation fk_rel, Relation pk_rel,
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HeapTuple old_tuple, HeapTuple new_tuple,
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bool detectNewRows, int expect_OK);
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static void ri_ExtractValues(Relation rel, HeapTuple tup,
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const RI_ConstraintInfo *riinfo, bool rel_is_pk,
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Datum *vals, char *nulls);
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static void ri_ReportViolation(const RI_ConstraintInfo *riinfo,
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Relation pk_rel, Relation fk_rel,
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HeapTuple violator, TupleDesc tupdesc,
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int queryno) pg_attribute_noreturn();
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/* ----------
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* RI_FKey_check -
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*
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* Check foreign key existence (combined for INSERT and UPDATE).
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* ----------
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*/
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static Datum
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RI_FKey_check(TriggerData *trigdata)
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{
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const RI_ConstraintInfo *riinfo;
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Relation fk_rel;
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Relation pk_rel;
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HeapTuple new_row;
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Buffer new_row_buf;
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RI_QueryKey qkey;
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SPIPlanPtr qplan;
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int i;
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/*
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* Get arguments.
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*/
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riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
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trigdata->tg_relation, false);
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if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
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{
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new_row = trigdata->tg_newtuple;
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new_row_buf = trigdata->tg_newtuplebuf;
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}
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else
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{
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new_row = trigdata->tg_trigtuple;
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new_row_buf = trigdata->tg_trigtuplebuf;
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}
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/*
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* We should not even consider checking the row if it is no longer valid,
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* since it was either deleted (so the deferred check should be skipped)
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* or updated (in which case only the latest version of the row should be
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* checked). Test its liveness according to SnapshotSelf. We need pin
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* and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller
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* should be holding pin, but not lock.
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*/
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LockBuffer(new_row_buf, BUFFER_LOCK_SHARE);
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if (!HeapTupleSatisfiesVisibility(new_row, SnapshotSelf, new_row_buf))
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{
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LockBuffer(new_row_buf, BUFFER_LOCK_UNLOCK);
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return PointerGetDatum(NULL);
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}
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LockBuffer(new_row_buf, BUFFER_LOCK_UNLOCK);
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/*
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* Get the relation descriptors of the FK and PK tables.
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*
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* pk_rel is opened in RowShareLock mode since that's what our eventual
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* SELECT FOR KEY SHARE will get on it.
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*/
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fk_rel = trigdata->tg_relation;
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pk_rel = heap_open(riinfo->pk_relid, RowShareLock);
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if (riinfo->confmatchtype == FKCONSTR_MATCH_PARTIAL)
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("MATCH PARTIAL not yet implemented")));
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switch (ri_NullCheck(RelationGetDescr(fk_rel), new_row, riinfo, false))
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{
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case RI_KEYS_ALL_NULL:
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/*
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* No further check needed - an all-NULL key passes every type of
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* foreign key constraint.
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*/
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heap_close(pk_rel, RowShareLock);
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return PointerGetDatum(NULL);
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case RI_KEYS_SOME_NULL:
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/*
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* This is the only case that differs between the three kinds of
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* MATCH.
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*/
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switch (riinfo->confmatchtype)
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{
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case FKCONSTR_MATCH_FULL:
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/*
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* Not allowed - MATCH FULL says either all or none of the
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* attributes can be NULLs
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*/
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ereport(ERROR,
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(errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
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errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
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RelationGetRelationName(fk_rel),
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NameStr(riinfo->conname)),
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errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
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errtableconstraint(fk_rel,
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NameStr(riinfo->conname))));
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heap_close(pk_rel, RowShareLock);
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return PointerGetDatum(NULL);
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case FKCONSTR_MATCH_SIMPLE:
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/*
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* MATCH SIMPLE - if ANY column is null, the key passes
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* the constraint.
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*/
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heap_close(pk_rel, RowShareLock);
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return PointerGetDatum(NULL);
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case FKCONSTR_MATCH_PARTIAL:
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/*
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* MATCH PARTIAL - all non-null columns must match. (not
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* implemented, can be done by modifying the query below
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* to only include non-null columns, or by writing a
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* special version here)
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*/
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("MATCH PARTIAL not yet implemented")));
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heap_close(pk_rel, RowShareLock);
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return PointerGetDatum(NULL);
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default:
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elog(ERROR, "unrecognized confmatchtype: %d",
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riinfo->confmatchtype);
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break;
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}
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case RI_KEYS_NONE_NULL:
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/*
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* Have a full qualified key - continue below for all three kinds
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* of MATCH.
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*/
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break;
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}
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if (SPI_connect() != SPI_OK_CONNECT)
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elog(ERROR, "SPI_connect failed");
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/*
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* Fetch or prepare a saved plan for the real check
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*/
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ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK);
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if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
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{
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StringInfoData querybuf;
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char pkrelname[MAX_QUOTED_REL_NAME_LEN];
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char attname[MAX_QUOTED_NAME_LEN];
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char paramname[16];
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const char *querysep;
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Oid queryoids[RI_MAX_NUMKEYS];
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/* ----------
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* The query string built is
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* SELECT 1 FROM ONLY <pktable> x WHERE pkatt1 = $1 [AND ...]
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* FOR KEY SHARE OF x
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* The type id's for the $ parameters are those of the
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* corresponding FK attributes.
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* ----------
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*/
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initStringInfo(&querybuf);
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quoteRelationName(pkrelname, pk_rel);
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appendStringInfo(&querybuf, "SELECT 1 FROM ONLY %s x", pkrelname);
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querysep = "WHERE";
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for (i = 0; i < riinfo->nkeys; i++)
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{
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Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
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Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
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quoteOneName(attname,
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RIAttName(pk_rel, riinfo->pk_attnums[i]));
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sprintf(paramname, "$%d", i + 1);
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ri_GenerateQual(&querybuf, querysep,
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attname, pk_type,
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riinfo->pf_eq_oprs[i],
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paramname, fk_type);
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querysep = "AND";
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queryoids[i] = fk_type;
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}
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appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
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/* Prepare and save the plan */
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qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
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&qkey, fk_rel, pk_rel, true);
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}
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/*
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* Now check that foreign key exists in PK table
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*/
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ri_PerformCheck(riinfo, &qkey, qplan,
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fk_rel, pk_rel,
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NULL, new_row,
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false,
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SPI_OK_SELECT);
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if (SPI_finish() != SPI_OK_FINISH)
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elog(ERROR, "SPI_finish failed");
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heap_close(pk_rel, RowShareLock);
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return PointerGetDatum(NULL);
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}
|
|
|
|
|
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/* ----------
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* RI_FKey_check_ins -
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*
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* Check foreign key existence at insert event on FK table.
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* ----------
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*/
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Datum
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RI_FKey_check_ins(PG_FUNCTION_ARGS)
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{
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/*
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* Check that this is a valid trigger call on the right time and event.
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*/
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ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
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/*
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* Share code with UPDATE case.
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*/
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return RI_FKey_check((TriggerData *) fcinfo->context);
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}
|
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|
|
|
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/* ----------
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* RI_FKey_check_upd -
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*
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* Check foreign key existence at update event on FK table.
|
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* ----------
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*/
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Datum
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RI_FKey_check_upd(PG_FUNCTION_ARGS)
|
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{
|
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/*
|
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* Check that this is a valid trigger call on the right time and event.
|
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*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
|
|
|
|
/*
|
|
* Share code with INSERT case.
|
|
*/
|
|
return RI_FKey_check((TriggerData *) fcinfo->context);
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* ri_Check_Pk_Match
|
|
*
|
|
* Check to see if another PK row has been created that provides the same
|
|
* key values as the "old_row" that's been modified or deleted in our trigger
|
|
* event. Returns true if a match is found in the PK table.
|
|
*
|
|
* We assume the caller checked that the old_row contains no NULL key values,
|
|
* since otherwise a match is impossible.
|
|
* ----------
|
|
*/
|
|
static bool
|
|
ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
|
|
HeapTuple old_row,
|
|
const RI_ConstraintInfo *riinfo)
|
|
{
|
|
SPIPlanPtr qplan;
|
|
RI_QueryKey qkey;
|
|
int i;
|
|
bool result;
|
|
|
|
/* Only called for non-null rows */
|
|
Assert(ri_NullCheck(RelationGetDescr(fk_rel), old_row, riinfo, true) == RI_KEYS_NONE_NULL);
|
|
|
|
if (SPI_connect() != SPI_OK_CONNECT)
|
|
elog(ERROR, "SPI_connect failed");
|
|
|
|
/*
|
|
* Fetch or prepare a saved plan for checking PK table with values coming
|
|
* from a PK row
|
|
*/
|
|
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK_FROM_PK);
|
|
|
|
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
|
|
{
|
|
StringInfoData querybuf;
|
|
char pkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char attname[MAX_QUOTED_NAME_LEN];
|
|
char paramname[16];
|
|
const char *querysep;
|
|
Oid queryoids[RI_MAX_NUMKEYS];
|
|
|
|
/* ----------
|
|
* The query string built is
|
|
* SELECT 1 FROM ONLY <pktable> x WHERE pkatt1 = $1 [AND ...]
|
|
* FOR KEY SHARE OF x
|
|
* The type id's for the $ parameters are those of the
|
|
* PK attributes themselves.
|
|
* ----------
|
|
*/
|
|
initStringInfo(&querybuf);
|
|
quoteRelationName(pkrelname, pk_rel);
|
|
appendStringInfo(&querybuf, "SELECT 1 FROM ONLY %s x", pkrelname);
|
|
querysep = "WHERE";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
|
|
|
|
quoteOneName(attname,
|
|
RIAttName(pk_rel, riinfo->pk_attnums[i]));
|
|
sprintf(paramname, "$%d", i + 1);
|
|
ri_GenerateQual(&querybuf, querysep,
|
|
attname, pk_type,
|
|
riinfo->pp_eq_oprs[i],
|
|
paramname, pk_type);
|
|
querysep = "AND";
|
|
queryoids[i] = pk_type;
|
|
}
|
|
appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
|
|
|
|
/* Prepare and save the plan */
|
|
qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
|
|
&qkey, fk_rel, pk_rel, true);
|
|
}
|
|
|
|
/*
|
|
* We have a plan now. Run it.
|
|
*/
|
|
result = ri_PerformCheck(riinfo, &qkey, qplan,
|
|
fk_rel, pk_rel,
|
|
old_row, NULL,
|
|
true, /* treat like update */
|
|
SPI_OK_SELECT);
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
elog(ERROR, "SPI_finish failed");
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* RI_FKey_noaction_del -
|
|
*
|
|
* Give an error and roll back the current transaction if the
|
|
* delete has resulted in a violation of the given referential
|
|
* integrity constraint.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_noaction_del(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
|
|
|
|
/*
|
|
* Share code with RESTRICT/UPDATE cases.
|
|
*/
|
|
return ri_restrict((TriggerData *) fcinfo->context, true);
|
|
}
|
|
|
|
/* ----------
|
|
* RI_FKey_restrict_del -
|
|
*
|
|
* Restrict delete from PK table to rows unreferenced by foreign key.
|
|
*
|
|
* The SQL standard intends that this referential action occur exactly when
|
|
* the delete is performed, rather than after. This appears to be
|
|
* the only difference between "NO ACTION" and "RESTRICT". In Postgres
|
|
* we still implement this as an AFTER trigger, but it's non-deferrable.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_restrict_del(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
|
|
|
|
/*
|
|
* Share code with NO ACTION/UPDATE cases.
|
|
*/
|
|
return ri_restrict((TriggerData *) fcinfo->context, false);
|
|
}
|
|
|
|
/* ----------
|
|
* RI_FKey_noaction_upd -
|
|
*
|
|
* Give an error and roll back the current transaction if the
|
|
* update has resulted in a violation of the given referential
|
|
* integrity constraint.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
|
|
|
|
/*
|
|
* Share code with RESTRICT/DELETE cases.
|
|
*/
|
|
return ri_restrict((TriggerData *) fcinfo->context, true);
|
|
}
|
|
|
|
/* ----------
|
|
* RI_FKey_restrict_upd -
|
|
*
|
|
* Restrict update of PK to rows unreferenced by foreign key.
|
|
*
|
|
* The SQL standard intends that this referential action occur exactly when
|
|
* the update is performed, rather than after. This appears to be
|
|
* the only difference between "NO ACTION" and "RESTRICT". In Postgres
|
|
* we still implement this as an AFTER trigger, but it's non-deferrable.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
|
|
|
|
/*
|
|
* Share code with NO ACTION/DELETE cases.
|
|
*/
|
|
return ri_restrict((TriggerData *) fcinfo->context, false);
|
|
}
|
|
|
|
/* ----------
|
|
* ri_restrict -
|
|
*
|
|
* Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
|
|
* ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
|
|
* ----------
|
|
*/
|
|
static Datum
|
|
ri_restrict(TriggerData *trigdata, bool is_no_action)
|
|
{
|
|
const RI_ConstraintInfo *riinfo;
|
|
Relation fk_rel;
|
|
Relation pk_rel;
|
|
HeapTuple old_row;
|
|
RI_QueryKey qkey;
|
|
SPIPlanPtr qplan;
|
|
|
|
/*
|
|
* Get arguments.
|
|
*/
|
|
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
|
|
trigdata->tg_relation, true);
|
|
|
|
/*
|
|
* Get the relation descriptors of the FK and PK tables and the old tuple.
|
|
*
|
|
* fk_rel is opened in RowShareLock mode since that's what our eventual
|
|
* SELECT FOR KEY SHARE will get on it.
|
|
*/
|
|
fk_rel = heap_open(riinfo->fk_relid, RowShareLock);
|
|
pk_rel = trigdata->tg_relation;
|
|
old_row = trigdata->tg_trigtuple;
|
|
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
/* ----------
|
|
* SQL:2008 15.17 <Execution of referential actions>
|
|
* General rules 9) a) iv):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON DELETE RESTRICT
|
|
* General rules 10) a) iv):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON UPDATE RESTRICT
|
|
* ----------
|
|
*/
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
case FKCONSTR_MATCH_FULL:
|
|
switch (ri_NullCheck(RelationGetDescr(pk_rel), old_row, riinfo, true))
|
|
{
|
|
case RI_KEYS_ALL_NULL:
|
|
case RI_KEYS_SOME_NULL:
|
|
|
|
/*
|
|
* No check needed - there cannot be any reference to old
|
|
* key if it contains a NULL
|
|
*/
|
|
heap_close(fk_rel, RowShareLock);
|
|
return PointerGetDatum(NULL);
|
|
|
|
case RI_KEYS_NONE_NULL:
|
|
|
|
/*
|
|
* Have a full qualified key - continue below
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* In UPDATE, no need to do anything if old and new keys are equal
|
|
*/
|
|
if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
|
|
{
|
|
HeapTuple new_row = trigdata->tg_newtuple;
|
|
|
|
if (ri_KeysEqual(pk_rel, old_row, new_row, riinfo, true))
|
|
{
|
|
heap_close(fk_rel, RowShareLock);
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If another PK row now exists providing the old key values, we
|
|
* should not do anything. However, this check should only be
|
|
* made in the NO ACTION case; in RESTRICT cases we don't wish to
|
|
* allow another row to be substituted.
|
|
*/
|
|
if (is_no_action &&
|
|
ri_Check_Pk_Match(pk_rel, fk_rel, old_row, riinfo))
|
|
{
|
|
heap_close(fk_rel, RowShareLock);
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
|
|
if (SPI_connect() != SPI_OK_CONNECT)
|
|
elog(ERROR, "SPI_connect failed");
|
|
|
|
/*
|
|
* Fetch or prepare a saved plan for the restrict lookup (it's the
|
|
* same query for delete and update cases)
|
|
*/
|
|
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_RESTRICT_CHECKREF);
|
|
|
|
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
|
|
{
|
|
StringInfoData querybuf;
|
|
char fkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char attname[MAX_QUOTED_NAME_LEN];
|
|
char paramname[16];
|
|
const char *querysep;
|
|
Oid queryoids[RI_MAX_NUMKEYS];
|
|
int i;
|
|
|
|
/* ----------
|
|
* The query string built is
|
|
* SELECT 1 FROM ONLY <fktable> x WHERE $1 = fkatt1 [AND ...]
|
|
* FOR KEY SHARE OF x
|
|
* The type id's for the $ parameters are those of the
|
|
* corresponding PK attributes.
|
|
* ----------
|
|
*/
|
|
initStringInfo(&querybuf);
|
|
quoteRelationName(fkrelname, fk_rel);
|
|
appendStringInfo(&querybuf, "SELECT 1 FROM ONLY %s x",
|
|
fkrelname);
|
|
querysep = "WHERE";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
|
|
Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
|
|
|
|
quoteOneName(attname,
|
|
RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
sprintf(paramname, "$%d", i + 1);
|
|
ri_GenerateQual(&querybuf, querysep,
|
|
paramname, pk_type,
|
|
riinfo->pf_eq_oprs[i],
|
|
attname, fk_type);
|
|
querysep = "AND";
|
|
queryoids[i] = pk_type;
|
|
}
|
|
appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
|
|
|
|
/* Prepare and save the plan */
|
|
qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
|
|
&qkey, fk_rel, pk_rel, true);
|
|
}
|
|
|
|
/*
|
|
* We have a plan now. Run it to check for existing references.
|
|
*/
|
|
ri_PerformCheck(riinfo, &qkey, qplan,
|
|
fk_rel, pk_rel,
|
|
old_row, NULL,
|
|
true, /* must detect new rows */
|
|
SPI_OK_SELECT);
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
elog(ERROR, "SPI_finish failed");
|
|
|
|
heap_close(fk_rel, RowShareLock);
|
|
|
|
return PointerGetDatum(NULL);
|
|
|
|
/*
|
|
* Handle MATCH PARTIAL restrict delete or update.
|
|
*/
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
return PointerGetDatum(NULL);
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
|
|
/* Never reached */
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* RI_FKey_cascade_del -
|
|
*
|
|
* Cascaded delete foreign key references at delete event on PK table.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_cascade_del(PG_FUNCTION_ARGS)
|
|
{
|
|
TriggerData *trigdata = (TriggerData *) fcinfo->context;
|
|
const RI_ConstraintInfo *riinfo;
|
|
Relation fk_rel;
|
|
Relation pk_rel;
|
|
HeapTuple old_row;
|
|
RI_QueryKey qkey;
|
|
SPIPlanPtr qplan;
|
|
int i;
|
|
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
|
|
|
|
/*
|
|
* Get arguments.
|
|
*/
|
|
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
|
|
trigdata->tg_relation, true);
|
|
|
|
/*
|
|
* Get the relation descriptors of the FK and PK tables and the old tuple.
|
|
*
|
|
* fk_rel is opened in RowExclusiveLock mode since that's what our
|
|
* eventual DELETE will get on it.
|
|
*/
|
|
fk_rel = heap_open(riinfo->fk_relid, RowExclusiveLock);
|
|
pk_rel = trigdata->tg_relation;
|
|
old_row = trigdata->tg_trigtuple;
|
|
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
/* ----------
|
|
* SQL:2008 15.17 <Execution of referential actions>
|
|
* General rules 9) a) i):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON DELETE CASCADE
|
|
* ----------
|
|
*/
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
case FKCONSTR_MATCH_FULL:
|
|
switch (ri_NullCheck(RelationGetDescr(pk_rel), old_row, riinfo, true))
|
|
{
|
|
case RI_KEYS_ALL_NULL:
|
|
case RI_KEYS_SOME_NULL:
|
|
|
|
/*
|
|
* No check needed - there cannot be any reference to old
|
|
* key if it contains a NULL
|
|
*/
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
return PointerGetDatum(NULL);
|
|
|
|
case RI_KEYS_NONE_NULL:
|
|
|
|
/*
|
|
* Have a full qualified key - continue below
|
|
*/
|
|
break;
|
|
}
|
|
|
|
if (SPI_connect() != SPI_OK_CONNECT)
|
|
elog(ERROR, "SPI_connect failed");
|
|
|
|
/*
|
|
* Fetch or prepare a saved plan for the cascaded delete
|
|
*/
|
|
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_DEL_DODELETE);
|
|
|
|
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
|
|
{
|
|
StringInfoData querybuf;
|
|
char fkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char attname[MAX_QUOTED_NAME_LEN];
|
|
char paramname[16];
|
|
const char *querysep;
|
|
Oid queryoids[RI_MAX_NUMKEYS];
|
|
|
|
/* ----------
|
|
* The query string built is
|
|
* DELETE FROM ONLY <fktable> WHERE $1 = fkatt1 [AND ...]
|
|
* The type id's for the $ parameters are those of the
|
|
* corresponding PK attributes.
|
|
* ----------
|
|
*/
|
|
initStringInfo(&querybuf);
|
|
quoteRelationName(fkrelname, fk_rel);
|
|
appendStringInfo(&querybuf, "DELETE FROM ONLY %s", fkrelname);
|
|
querysep = "WHERE";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
|
|
Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
|
|
|
|
quoteOneName(attname,
|
|
RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
sprintf(paramname, "$%d", i + 1);
|
|
ri_GenerateQual(&querybuf, querysep,
|
|
paramname, pk_type,
|
|
riinfo->pf_eq_oprs[i],
|
|
attname, fk_type);
|
|
querysep = "AND";
|
|
queryoids[i] = pk_type;
|
|
}
|
|
|
|
/* Prepare and save the plan */
|
|
qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
|
|
&qkey, fk_rel, pk_rel, true);
|
|
}
|
|
|
|
/*
|
|
* We have a plan now. Build up the arguments from the key values
|
|
* in the deleted PK tuple and delete the referencing rows
|
|
*/
|
|
ri_PerformCheck(riinfo, &qkey, qplan,
|
|
fk_rel, pk_rel,
|
|
old_row, NULL,
|
|
true, /* must detect new rows */
|
|
SPI_OK_DELETE);
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
elog(ERROR, "SPI_finish failed");
|
|
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
|
|
return PointerGetDatum(NULL);
|
|
|
|
/*
|
|
* Handle MATCH PARTIAL cascaded delete.
|
|
*/
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
return PointerGetDatum(NULL);
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
|
|
/* Never reached */
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* RI_FKey_cascade_upd -
|
|
*
|
|
* Cascaded update foreign key references at update event on PK table.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
|
|
{
|
|
TriggerData *trigdata = (TriggerData *) fcinfo->context;
|
|
const RI_ConstraintInfo *riinfo;
|
|
Relation fk_rel;
|
|
Relation pk_rel;
|
|
HeapTuple new_row;
|
|
HeapTuple old_row;
|
|
RI_QueryKey qkey;
|
|
SPIPlanPtr qplan;
|
|
int i;
|
|
int j;
|
|
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
|
|
|
|
/*
|
|
* Get arguments.
|
|
*/
|
|
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
|
|
trigdata->tg_relation, true);
|
|
|
|
/*
|
|
* Get the relation descriptors of the FK and PK tables and the new and
|
|
* old tuple.
|
|
*
|
|
* fk_rel is opened in RowExclusiveLock mode since that's what our
|
|
* eventual UPDATE will get on it.
|
|
*/
|
|
fk_rel = heap_open(riinfo->fk_relid, RowExclusiveLock);
|
|
pk_rel = trigdata->tg_relation;
|
|
new_row = trigdata->tg_newtuple;
|
|
old_row = trigdata->tg_trigtuple;
|
|
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
/* ----------
|
|
* SQL:2008 15.17 <Execution of referential actions>
|
|
* General rules 10) a) i):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON UPDATE CASCADE
|
|
* ----------
|
|
*/
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
case FKCONSTR_MATCH_FULL:
|
|
switch (ri_NullCheck(RelationGetDescr(pk_rel), old_row, riinfo, true))
|
|
{
|
|
case RI_KEYS_ALL_NULL:
|
|
case RI_KEYS_SOME_NULL:
|
|
|
|
/*
|
|
* No check needed - there cannot be any reference to old
|
|
* key if it contains a NULL
|
|
*/
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
return PointerGetDatum(NULL);
|
|
|
|
case RI_KEYS_NONE_NULL:
|
|
|
|
/*
|
|
* Have a full qualified key - continue below
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* No need to do anything if old and new keys are equal
|
|
*/
|
|
if (ri_KeysEqual(pk_rel, old_row, new_row, riinfo, true))
|
|
{
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
|
|
if (SPI_connect() != SPI_OK_CONNECT)
|
|
elog(ERROR, "SPI_connect failed");
|
|
|
|
/*
|
|
* Fetch or prepare a saved plan for the cascaded update
|
|
*/
|
|
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_UPD_DOUPDATE);
|
|
|
|
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
|
|
{
|
|
StringInfoData querybuf;
|
|
StringInfoData qualbuf;
|
|
char fkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char attname[MAX_QUOTED_NAME_LEN];
|
|
char paramname[16];
|
|
const char *querysep;
|
|
const char *qualsep;
|
|
Oid queryoids[RI_MAX_NUMKEYS * 2];
|
|
|
|
/* ----------
|
|
* The query string built is
|
|
* UPDATE ONLY <fktable> SET fkatt1 = $1 [, ...]
|
|
* WHERE $n = fkatt1 [AND ...]
|
|
* The type id's for the $ parameters are those of the
|
|
* corresponding PK attributes. Note that we are assuming
|
|
* there is an assignment cast from the PK to the FK type;
|
|
* else the parser will fail.
|
|
* ----------
|
|
*/
|
|
initStringInfo(&querybuf);
|
|
initStringInfo(&qualbuf);
|
|
quoteRelationName(fkrelname, fk_rel);
|
|
appendStringInfo(&querybuf, "UPDATE ONLY %s SET", fkrelname);
|
|
querysep = "";
|
|
qualsep = "WHERE";
|
|
for (i = 0, j = riinfo->nkeys; i < riinfo->nkeys; i++, j++)
|
|
{
|
|
Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
|
|
Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
|
|
|
|
quoteOneName(attname,
|
|
RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
appendStringInfo(&querybuf,
|
|
"%s %s = $%d",
|
|
querysep, attname, i + 1);
|
|
sprintf(paramname, "$%d", j + 1);
|
|
ri_GenerateQual(&qualbuf, qualsep,
|
|
paramname, pk_type,
|
|
riinfo->pf_eq_oprs[i],
|
|
attname, fk_type);
|
|
querysep = ",";
|
|
qualsep = "AND";
|
|
queryoids[i] = pk_type;
|
|
queryoids[j] = pk_type;
|
|
}
|
|
appendStringInfoString(&querybuf, qualbuf.data);
|
|
|
|
/* Prepare and save the plan */
|
|
qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys * 2, queryoids,
|
|
&qkey, fk_rel, pk_rel, true);
|
|
}
|
|
|
|
/*
|
|
* We have a plan now. Run it to update the existing references.
|
|
*/
|
|
ri_PerformCheck(riinfo, &qkey, qplan,
|
|
fk_rel, pk_rel,
|
|
old_row, new_row,
|
|
true, /* must detect new rows */
|
|
SPI_OK_UPDATE);
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
elog(ERROR, "SPI_finish failed");
|
|
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
|
|
return PointerGetDatum(NULL);
|
|
|
|
/*
|
|
* Handle MATCH PARTIAL cascade update.
|
|
*/
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
return PointerGetDatum(NULL);
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
|
|
/* Never reached */
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* RI_FKey_setnull_del -
|
|
*
|
|
* Set foreign key references to NULL values at delete event on PK table.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_setnull_del(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
|
|
|
|
/*
|
|
* Share code with UPDATE case
|
|
*/
|
|
return ri_setnull((TriggerData *) fcinfo->context);
|
|
}
|
|
|
|
/* ----------
|
|
* RI_FKey_setnull_upd -
|
|
*
|
|
* Set foreign key references to NULL at update event on PK table.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
|
|
|
|
/*
|
|
* Share code with DELETE case
|
|
*/
|
|
return ri_setnull((TriggerData *) fcinfo->context);
|
|
}
|
|
|
|
/* ----------
|
|
* ri_setnull -
|
|
*
|
|
* Common code for ON DELETE SET NULL and ON UPDATE SET NULL
|
|
* ----------
|
|
*/
|
|
static Datum
|
|
ri_setnull(TriggerData *trigdata)
|
|
{
|
|
const RI_ConstraintInfo *riinfo;
|
|
Relation fk_rel;
|
|
Relation pk_rel;
|
|
HeapTuple old_row;
|
|
RI_QueryKey qkey;
|
|
SPIPlanPtr qplan;
|
|
int i;
|
|
|
|
/*
|
|
* Get arguments.
|
|
*/
|
|
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
|
|
trigdata->tg_relation, true);
|
|
|
|
/*
|
|
* Get the relation descriptors of the FK and PK tables and the old tuple.
|
|
*
|
|
* fk_rel is opened in RowExclusiveLock mode since that's what our
|
|
* eventual UPDATE will get on it.
|
|
*/
|
|
fk_rel = heap_open(riinfo->fk_relid, RowExclusiveLock);
|
|
pk_rel = trigdata->tg_relation;
|
|
old_row = trigdata->tg_trigtuple;
|
|
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
/* ----------
|
|
* SQL:2008 15.17 <Execution of referential actions>
|
|
* General rules 9) a) ii):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON DELETE SET NULL
|
|
* General rules 10) a) ii):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON UPDATE SET NULL
|
|
* ----------
|
|
*/
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
case FKCONSTR_MATCH_FULL:
|
|
switch (ri_NullCheck(RelationGetDescr(pk_rel), old_row, riinfo, true))
|
|
{
|
|
case RI_KEYS_ALL_NULL:
|
|
case RI_KEYS_SOME_NULL:
|
|
|
|
/*
|
|
* No check needed - there cannot be any reference to old
|
|
* key if it contains a NULL
|
|
*/
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
return PointerGetDatum(NULL);
|
|
|
|
case RI_KEYS_NONE_NULL:
|
|
|
|
/*
|
|
* Have a full qualified key - continue below
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* In UPDATE, no need to do anything if old and new keys are equal
|
|
*/
|
|
if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
|
|
{
|
|
HeapTuple new_row = trigdata->tg_newtuple;
|
|
|
|
if (ri_KeysEqual(pk_rel, old_row, new_row, riinfo, true))
|
|
{
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
}
|
|
|
|
if (SPI_connect() != SPI_OK_CONNECT)
|
|
elog(ERROR, "SPI_connect failed");
|
|
|
|
/*
|
|
* Fetch or prepare a saved plan for the set null operation (it's
|
|
* the same query for delete and update cases)
|
|
*/
|
|
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_SETNULL_DOUPDATE);
|
|
|
|
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
|
|
{
|
|
StringInfoData querybuf;
|
|
StringInfoData qualbuf;
|
|
char fkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char attname[MAX_QUOTED_NAME_LEN];
|
|
char paramname[16];
|
|
const char *querysep;
|
|
const char *qualsep;
|
|
Oid queryoids[RI_MAX_NUMKEYS];
|
|
|
|
/* ----------
|
|
* The query string built is
|
|
* UPDATE ONLY <fktable> SET fkatt1 = NULL [, ...]
|
|
* WHERE $1 = fkatt1 [AND ...]
|
|
* The type id's for the $ parameters are those of the
|
|
* corresponding PK attributes.
|
|
* ----------
|
|
*/
|
|
initStringInfo(&querybuf);
|
|
initStringInfo(&qualbuf);
|
|
quoteRelationName(fkrelname, fk_rel);
|
|
appendStringInfo(&querybuf, "UPDATE ONLY %s SET", fkrelname);
|
|
querysep = "";
|
|
qualsep = "WHERE";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
|
|
Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
|
|
|
|
quoteOneName(attname,
|
|
RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
appendStringInfo(&querybuf,
|
|
"%s %s = NULL",
|
|
querysep, attname);
|
|
sprintf(paramname, "$%d", i + 1);
|
|
ri_GenerateQual(&qualbuf, qualsep,
|
|
paramname, pk_type,
|
|
riinfo->pf_eq_oprs[i],
|
|
attname, fk_type);
|
|
querysep = ",";
|
|
qualsep = "AND";
|
|
queryoids[i] = pk_type;
|
|
}
|
|
appendStringInfoString(&querybuf, qualbuf.data);
|
|
|
|
/* Prepare and save the plan */
|
|
qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
|
|
&qkey, fk_rel, pk_rel, true);
|
|
}
|
|
|
|
/*
|
|
* We have a plan now. Run it to update the existing references.
|
|
*/
|
|
ri_PerformCheck(riinfo, &qkey, qplan,
|
|
fk_rel, pk_rel,
|
|
old_row, NULL,
|
|
true, /* must detect new rows */
|
|
SPI_OK_UPDATE);
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
elog(ERROR, "SPI_finish failed");
|
|
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
|
|
return PointerGetDatum(NULL);
|
|
|
|
/*
|
|
* Handle MATCH PARTIAL set null delete or update.
|
|
*/
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
return PointerGetDatum(NULL);
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
|
|
/* Never reached */
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* RI_FKey_setdefault_del -
|
|
*
|
|
* Set foreign key references to defaults at delete event on PK table.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
|
|
|
|
/*
|
|
* Share code with UPDATE case
|
|
*/
|
|
return ri_setdefault((TriggerData *) fcinfo->context);
|
|
}
|
|
|
|
/* ----------
|
|
* RI_FKey_setdefault_upd -
|
|
*
|
|
* Set foreign key references to defaults at update event on PK table.
|
|
* ----------
|
|
*/
|
|
Datum
|
|
RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
|
|
{
|
|
/*
|
|
* Check that this is a valid trigger call on the right time and event.
|
|
*/
|
|
ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
|
|
|
|
/*
|
|
* Share code with DELETE case
|
|
*/
|
|
return ri_setdefault((TriggerData *) fcinfo->context);
|
|
}
|
|
|
|
/* ----------
|
|
* ri_setdefault -
|
|
*
|
|
* Common code for ON DELETE SET DEFAULT and ON UPDATE SET DEFAULT
|
|
* ----------
|
|
*/
|
|
static Datum
|
|
ri_setdefault(TriggerData *trigdata)
|
|
{
|
|
const RI_ConstraintInfo *riinfo;
|
|
Relation fk_rel;
|
|
Relation pk_rel;
|
|
HeapTuple old_row;
|
|
RI_QueryKey qkey;
|
|
SPIPlanPtr qplan;
|
|
|
|
/*
|
|
* Get arguments.
|
|
*/
|
|
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
|
|
trigdata->tg_relation, true);
|
|
|
|
/*
|
|
* Get the relation descriptors of the FK and PK tables and the old tuple.
|
|
*
|
|
* fk_rel is opened in RowExclusiveLock mode since that's what our
|
|
* eventual UPDATE will get on it.
|
|
*/
|
|
fk_rel = heap_open(riinfo->fk_relid, RowExclusiveLock);
|
|
pk_rel = trigdata->tg_relation;
|
|
old_row = trigdata->tg_trigtuple;
|
|
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
/* ----------
|
|
* SQL:2008 15.17 <Execution of referential actions>
|
|
* General rules 9) a) iii):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON DELETE SET DEFAULT
|
|
* General rules 10) a) iii):
|
|
* MATCH SIMPLE/FULL
|
|
* ... ON UPDATE SET DEFAULT
|
|
* ----------
|
|
*/
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
case FKCONSTR_MATCH_FULL:
|
|
switch (ri_NullCheck(RelationGetDescr(pk_rel), old_row, riinfo, true))
|
|
{
|
|
case RI_KEYS_ALL_NULL:
|
|
case RI_KEYS_SOME_NULL:
|
|
|
|
/*
|
|
* No check needed - there cannot be any reference to old
|
|
* key if it contains a NULL
|
|
*/
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
return PointerGetDatum(NULL);
|
|
|
|
case RI_KEYS_NONE_NULL:
|
|
|
|
/*
|
|
* Have a full qualified key - continue below
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* In UPDATE, no need to do anything if old and new keys are equal
|
|
*/
|
|
if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
|
|
{
|
|
HeapTuple new_row = trigdata->tg_newtuple;
|
|
|
|
if (ri_KeysEqual(pk_rel, old_row, new_row, riinfo, true))
|
|
{
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
}
|
|
|
|
if (SPI_connect() != SPI_OK_CONNECT)
|
|
elog(ERROR, "SPI_connect failed");
|
|
|
|
/*
|
|
* Fetch or prepare a saved plan for the set default operation
|
|
* (it's the same query for delete and update cases)
|
|
*/
|
|
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_SETDEFAULT_DOUPDATE);
|
|
|
|
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
|
|
{
|
|
StringInfoData querybuf;
|
|
StringInfoData qualbuf;
|
|
char fkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char attname[MAX_QUOTED_NAME_LEN];
|
|
char paramname[16];
|
|
const char *querysep;
|
|
const char *qualsep;
|
|
Oid queryoids[RI_MAX_NUMKEYS];
|
|
int i;
|
|
|
|
/* ----------
|
|
* The query string built is
|
|
* UPDATE ONLY <fktable> SET fkatt1 = DEFAULT [, ...]
|
|
* WHERE $1 = fkatt1 [AND ...]
|
|
* The type id's for the $ parameters are those of the
|
|
* corresponding PK attributes.
|
|
* ----------
|
|
*/
|
|
initStringInfo(&querybuf);
|
|
initStringInfo(&qualbuf);
|
|
quoteRelationName(fkrelname, fk_rel);
|
|
appendStringInfo(&querybuf, "UPDATE ONLY %s SET", fkrelname);
|
|
querysep = "";
|
|
qualsep = "WHERE";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
|
|
Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
|
|
|
|
quoteOneName(attname,
|
|
RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
appendStringInfo(&querybuf,
|
|
"%s %s = DEFAULT",
|
|
querysep, attname);
|
|
sprintf(paramname, "$%d", i + 1);
|
|
ri_GenerateQual(&qualbuf, qualsep,
|
|
paramname, pk_type,
|
|
riinfo->pf_eq_oprs[i],
|
|
attname, fk_type);
|
|
querysep = ",";
|
|
qualsep = "AND";
|
|
queryoids[i] = pk_type;
|
|
}
|
|
appendStringInfoString(&querybuf, qualbuf.data);
|
|
|
|
/* Prepare and save the plan */
|
|
qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
|
|
&qkey, fk_rel, pk_rel, true);
|
|
}
|
|
|
|
/*
|
|
* We have a plan now. Run it to update the existing references.
|
|
*/
|
|
ri_PerformCheck(riinfo, &qkey, qplan,
|
|
fk_rel, pk_rel,
|
|
old_row, NULL,
|
|
true, /* must detect new rows */
|
|
SPI_OK_UPDATE);
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
elog(ERROR, "SPI_finish failed");
|
|
|
|
heap_close(fk_rel, RowExclusiveLock);
|
|
|
|
/*
|
|
* If we just deleted or updated the PK row whose key was equal to
|
|
* the FK columns' default values, and a referencing row exists in
|
|
* the FK table, we would have updated that row to the same values
|
|
* it already had --- and RI_FKey_fk_upd_check_required would
|
|
* hence believe no check is necessary. So we need to do another
|
|
* lookup now and in case a reference still exists, abort the
|
|
* operation. That is already implemented in the NO ACTION
|
|
* trigger, so just run it. (This recheck is only needed in the
|
|
* SET DEFAULT case, since CASCADE would remove such rows in case
|
|
* of a DELETE operation or would change the FK key values in case
|
|
* of an UPDATE, while SET NULL is certain to result in rows that
|
|
* satisfy the FK constraint.)
|
|
*/
|
|
return ri_restrict(trigdata, true);
|
|
|
|
/*
|
|
* Handle MATCH PARTIAL set default delete or update.
|
|
*/
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
return PointerGetDatum(NULL);
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
|
|
/* Never reached */
|
|
return PointerGetDatum(NULL);
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* RI_FKey_pk_upd_check_required -
|
|
*
|
|
* Check if we really need to fire the RI trigger for an update to a PK
|
|
* relation. This is called by the AFTER trigger queue manager to see if
|
|
* it can skip queuing an instance of an RI trigger. Returns true if the
|
|
* trigger must be fired, false if we can prove the constraint will still
|
|
* be satisfied.
|
|
* ----------
|
|
*/
|
|
bool
|
|
RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel,
|
|
HeapTuple old_row, HeapTuple new_row)
|
|
{
|
|
const RI_ConstraintInfo *riinfo;
|
|
|
|
/*
|
|
* Get arguments.
|
|
*/
|
|
riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
|
|
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
case FKCONSTR_MATCH_FULL:
|
|
|
|
/*
|
|
* If any old key value is NULL, the row could not have been
|
|
* referenced by an FK row, so no check is needed.
|
|
*/
|
|
if (ri_NullCheck(RelationGetDescr(pk_rel), old_row, riinfo, true) != RI_KEYS_NONE_NULL)
|
|
return false;
|
|
|
|
/* If all old and new key values are equal, no check is needed */
|
|
if (ri_KeysEqual(pk_rel, old_row, new_row, riinfo, true))
|
|
return false;
|
|
|
|
/* Else we need to fire the trigger. */
|
|
return true;
|
|
|
|
/* Handle MATCH PARTIAL check. */
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
break;
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
|
|
/* Never reached */
|
|
return false;
|
|
}
|
|
|
|
/* ----------
|
|
* RI_FKey_fk_upd_check_required -
|
|
*
|
|
* Check if we really need to fire the RI trigger for an update to an FK
|
|
* relation. This is called by the AFTER trigger queue manager to see if
|
|
* it can skip queuing an instance of an RI trigger. Returns true if the
|
|
* trigger must be fired, false if we can prove the constraint will still
|
|
* be satisfied.
|
|
* ----------
|
|
*/
|
|
bool
|
|
RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel,
|
|
HeapTuple old_row, HeapTuple new_row)
|
|
{
|
|
const RI_ConstraintInfo *riinfo;
|
|
|
|
/*
|
|
* Get arguments.
|
|
*/
|
|
riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
|
|
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
|
|
/*
|
|
* If any new key value is NULL, the row must satisfy the
|
|
* constraint, so no check is needed.
|
|
*/
|
|
if (ri_NullCheck(RelationGetDescr(fk_rel), new_row, riinfo, false) != RI_KEYS_NONE_NULL)
|
|
return false;
|
|
|
|
/*
|
|
* If the original row was inserted by our own transaction, we
|
|
* must fire the trigger whether or not the keys are equal. This
|
|
* is because our UPDATE will invalidate the INSERT so that the
|
|
* INSERT RI trigger will not do anything; so we had better do the
|
|
* UPDATE check. (We could skip this if we knew the INSERT
|
|
* trigger already fired, but there is no easy way to know that.)
|
|
*/
|
|
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(old_row->t_data)))
|
|
return true;
|
|
|
|
/* If all old and new key values are equal, no check is needed */
|
|
if (ri_KeysEqual(fk_rel, old_row, new_row, riinfo, false))
|
|
return false;
|
|
|
|
/* Else we need to fire the trigger. */
|
|
return true;
|
|
|
|
case FKCONSTR_MATCH_FULL:
|
|
|
|
/*
|
|
* If all new key values are NULL, the row must satisfy the
|
|
* constraint, so no check is needed. On the other hand, if only
|
|
* some of them are NULL, the row must fail the constraint. We
|
|
* must not throw error here, because the row might get
|
|
* invalidated before the constraint is to be checked, but we
|
|
* should queue the event to apply the check later.
|
|
*/
|
|
switch (ri_NullCheck(RelationGetDescr(fk_rel), new_row, riinfo, false))
|
|
{
|
|
case RI_KEYS_ALL_NULL:
|
|
return false;
|
|
case RI_KEYS_SOME_NULL:
|
|
return true;
|
|
case RI_KEYS_NONE_NULL:
|
|
break; /* continue with the check */
|
|
}
|
|
|
|
/*
|
|
* If the original row was inserted by our own transaction, we
|
|
* must fire the trigger whether or not the keys are equal. This
|
|
* is because our UPDATE will invalidate the INSERT so that the
|
|
* INSERT RI trigger will not do anything; so we had better do the
|
|
* UPDATE check. (We could skip this if we knew the INSERT
|
|
* trigger already fired, but there is no easy way to know that.)
|
|
*/
|
|
if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(old_row->t_data)))
|
|
return true;
|
|
|
|
/* If all old and new key values are equal, no check is needed */
|
|
if (ri_KeysEqual(fk_rel, old_row, new_row, riinfo, false))
|
|
return false;
|
|
|
|
/* Else we need to fire the trigger. */
|
|
return true;
|
|
|
|
/* Handle MATCH PARTIAL check. */
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
break;
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
|
|
/* Never reached */
|
|
return false;
|
|
}
|
|
|
|
/* ----------
|
|
* RI_Initial_Check -
|
|
*
|
|
* Check an entire table for non-matching values using a single query.
|
|
* This is not a trigger procedure, but is called during ALTER TABLE
|
|
* ADD FOREIGN KEY to validate the initial table contents.
|
|
*
|
|
* We expect that the caller has made provision to prevent any problems
|
|
* caused by concurrent actions. This could be either by locking rel and
|
|
* pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
|
|
* that triggers implementing the checks are already active.
|
|
* Hence, we do not need to lock individual rows for the check.
|
|
*
|
|
* If the check fails because the current user doesn't have permissions
|
|
* to read both tables, return false to let our caller know that they will
|
|
* need to do something else to check the constraint.
|
|
* ----------
|
|
*/
|
|
bool
|
|
RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
|
|
{
|
|
const RI_ConstraintInfo *riinfo;
|
|
StringInfoData querybuf;
|
|
char pkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char fkrelname[MAX_QUOTED_REL_NAME_LEN];
|
|
char pkattname[MAX_QUOTED_NAME_LEN + 3];
|
|
char fkattname[MAX_QUOTED_NAME_LEN + 3];
|
|
RangeTblEntry *pkrte;
|
|
RangeTblEntry *fkrte;
|
|
const char *sep;
|
|
int i;
|
|
int save_nestlevel;
|
|
char workmembuf[32];
|
|
int spi_result;
|
|
SPIPlanPtr qplan;
|
|
|
|
/* Fetch constraint info. */
|
|
riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
|
|
|
|
/*
|
|
* Check to make sure current user has enough permissions to do the test
|
|
* query. (If not, caller can fall back to the trigger method, which
|
|
* works because it changes user IDs on the fly.)
|
|
*
|
|
* XXX are there any other show-stopper conditions to check?
|
|
*/
|
|
pkrte = makeNode(RangeTblEntry);
|
|
pkrte->rtekind = RTE_RELATION;
|
|
pkrte->relid = RelationGetRelid(pk_rel);
|
|
pkrte->relkind = pk_rel->rd_rel->relkind;
|
|
pkrte->requiredPerms = ACL_SELECT;
|
|
|
|
fkrte = makeNode(RangeTblEntry);
|
|
fkrte->rtekind = RTE_RELATION;
|
|
fkrte->relid = RelationGetRelid(fk_rel);
|
|
fkrte->relkind = fk_rel->rd_rel->relkind;
|
|
fkrte->requiredPerms = ACL_SELECT;
|
|
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
int attno;
|
|
|
|
attno = riinfo->pk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
|
|
pkrte->selectedCols = bms_add_member(pkrte->selectedCols, attno);
|
|
|
|
attno = riinfo->fk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
|
|
fkrte->selectedCols = bms_add_member(fkrte->selectedCols, attno);
|
|
}
|
|
|
|
if (!ExecCheckRTPerms(list_make2(fkrte, pkrte), false))
|
|
return false;
|
|
|
|
/*
|
|
* Also punt if RLS is enabled on either table unless this role has the
|
|
* bypassrls right or is the table owner of the table(s) involved which
|
|
* have RLS enabled.
|
|
*/
|
|
if (!has_bypassrls_privilege(GetUserId()) &&
|
|
((pk_rel->rd_rel->relrowsecurity &&
|
|
!pg_class_ownercheck(pkrte->relid, GetUserId())) ||
|
|
(fk_rel->rd_rel->relrowsecurity &&
|
|
!pg_class_ownercheck(fkrte->relid, GetUserId()))))
|
|
return false;
|
|
|
|
/*----------
|
|
* The query string built is:
|
|
* SELECT fk.keycols FROM ONLY relname fk
|
|
* LEFT OUTER JOIN ONLY pkrelname pk
|
|
* ON (pk.pkkeycol1=fk.keycol1 [AND ...])
|
|
* WHERE pk.pkkeycol1 IS NULL AND
|
|
* For MATCH SIMPLE:
|
|
* (fk.keycol1 IS NOT NULL [AND ...])
|
|
* For MATCH FULL:
|
|
* (fk.keycol1 IS NOT NULL [OR ...])
|
|
*
|
|
* We attach COLLATE clauses to the operators when comparing columns
|
|
* that have different collations.
|
|
*----------
|
|
*/
|
|
initStringInfo(&querybuf);
|
|
appendStringInfoString(&querybuf, "SELECT ");
|
|
sep = "";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
quoteOneName(fkattname,
|
|
RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
|
|
sep = ", ";
|
|
}
|
|
|
|
quoteRelationName(pkrelname, pk_rel);
|
|
quoteRelationName(fkrelname, fk_rel);
|
|
appendStringInfo(&querybuf,
|
|
" FROM ONLY %s fk LEFT OUTER JOIN ONLY %s pk ON",
|
|
fkrelname, pkrelname);
|
|
|
|
strcpy(pkattname, "pk.");
|
|
strcpy(fkattname, "fk.");
|
|
sep = "(";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
|
|
Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
|
|
Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
|
|
Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
|
|
|
|
quoteOneName(pkattname + 3,
|
|
RIAttName(pk_rel, riinfo->pk_attnums[i]));
|
|
quoteOneName(fkattname + 3,
|
|
RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
ri_GenerateQual(&querybuf, sep,
|
|
pkattname, pk_type,
|
|
riinfo->pf_eq_oprs[i],
|
|
fkattname, fk_type);
|
|
if (pk_coll != fk_coll)
|
|
ri_GenerateQualCollation(&querybuf, pk_coll);
|
|
sep = "AND";
|
|
}
|
|
|
|
/*
|
|
* It's sufficient to test any one pk attribute for null to detect a join
|
|
* failure.
|
|
*/
|
|
quoteOneName(pkattname, RIAttName(pk_rel, riinfo->pk_attnums[0]));
|
|
appendStringInfo(&querybuf, ") WHERE pk.%s IS NULL AND (", pkattname);
|
|
|
|
sep = "";
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
|
|
appendStringInfo(&querybuf,
|
|
"%sfk.%s IS NOT NULL",
|
|
sep, fkattname);
|
|
switch (riinfo->confmatchtype)
|
|
{
|
|
case FKCONSTR_MATCH_SIMPLE:
|
|
sep = " AND ";
|
|
break;
|
|
case FKCONSTR_MATCH_FULL:
|
|
sep = " OR ";
|
|
break;
|
|
case FKCONSTR_MATCH_PARTIAL:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("MATCH PARTIAL not yet implemented")));
|
|
break;
|
|
default:
|
|
elog(ERROR, "unrecognized confmatchtype: %d",
|
|
riinfo->confmatchtype);
|
|
break;
|
|
}
|
|
}
|
|
appendStringInfoChar(&querybuf, ')');
|
|
|
|
/*
|
|
* Temporarily increase work_mem so that the check query can be executed
|
|
* more efficiently. It seems okay to do this because the query is simple
|
|
* enough to not use a multiple of work_mem, and one typically would not
|
|
* have many large foreign-key validations happening concurrently. So
|
|
* this seems to meet the criteria for being considered a "maintenance"
|
|
* operation, and accordingly we use maintenance_work_mem.
|
|
*
|
|
* We use the equivalent of a function SET option to allow the setting to
|
|
* persist for exactly the duration of the check query. guc.c also takes
|
|
* care of undoing the setting on error.
|
|
*/
|
|
save_nestlevel = NewGUCNestLevel();
|
|
|
|
snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
|
|
(void) set_config_option("work_mem", workmembuf,
|
|
PGC_USERSET, PGC_S_SESSION,
|
|
GUC_ACTION_SAVE, true, 0, false);
|
|
|
|
if (SPI_connect() != SPI_OK_CONNECT)
|
|
elog(ERROR, "SPI_connect failed");
|
|
|
|
/*
|
|
* Generate the plan. We don't need to cache it, and there are no
|
|
* arguments to the plan.
|
|
*/
|
|
qplan = SPI_prepare(querybuf.data, 0, NULL);
|
|
|
|
if (qplan == NULL)
|
|
elog(ERROR, "SPI_prepare returned %s for %s",
|
|
SPI_result_code_string(SPI_result), querybuf.data);
|
|
|
|
/*
|
|
* Run the plan. For safety we force a current snapshot to be used. (In
|
|
* transaction-snapshot mode, this arguably violates transaction isolation
|
|
* rules, but we really haven't got much choice.) We don't need to
|
|
* register the snapshot, because SPI_execute_snapshot will see to it. We
|
|
* need at most one tuple returned, so pass limit = 1.
|
|
*/
|
|
spi_result = SPI_execute_snapshot(qplan,
|
|
NULL, NULL,
|
|
GetLatestSnapshot(),
|
|
InvalidSnapshot,
|
|
true, false, 1);
|
|
|
|
/* Check result */
|
|
if (spi_result != SPI_OK_SELECT)
|
|
elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
|
|
|
|
/* Did we find a tuple violating the constraint? */
|
|
if (SPI_processed > 0)
|
|
{
|
|
HeapTuple tuple = SPI_tuptable->vals[0];
|
|
TupleDesc tupdesc = SPI_tuptable->tupdesc;
|
|
RI_ConstraintInfo fake_riinfo;
|
|
|
|
/*
|
|
* The columns to look at in the result tuple are 1..N, not whatever
|
|
* they are in the fk_rel. Hack up riinfo so that the subroutines
|
|
* called here will behave properly.
|
|
*
|
|
* In addition to this, we have to pass the correct tupdesc to
|
|
* ri_ReportViolation, overriding its normal habit of using the pk_rel
|
|
* or fk_rel's tupdesc.
|
|
*/
|
|
memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
|
|
for (i = 0; i < fake_riinfo.nkeys; i++)
|
|
fake_riinfo.fk_attnums[i] = i + 1;
|
|
|
|
/*
|
|
* If it's MATCH FULL, and there are any nulls in the FK keys,
|
|
* complain about that rather than the lack of a match. MATCH FULL
|
|
* disallows partially-null FK rows.
|
|
*/
|
|
if (fake_riinfo.confmatchtype == FKCONSTR_MATCH_FULL &&
|
|
ri_NullCheck(tupdesc, tuple, &fake_riinfo, false) != RI_KEYS_NONE_NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
|
|
errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
|
|
RelationGetRelationName(fk_rel),
|
|
NameStr(fake_riinfo.conname)),
|
|
errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
|
|
errtableconstraint(fk_rel,
|
|
NameStr(fake_riinfo.conname))));
|
|
|
|
/*
|
|
* We tell ri_ReportViolation we were doing the RI_PLAN_CHECK_LOOKUPPK
|
|
* query, which isn't true, but will cause it to use
|
|
* fake_riinfo.fk_attnums as we need.
|
|
*/
|
|
ri_ReportViolation(&fake_riinfo,
|
|
pk_rel, fk_rel,
|
|
tuple, tupdesc,
|
|
RI_PLAN_CHECK_LOOKUPPK);
|
|
}
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
elog(ERROR, "SPI_finish failed");
|
|
|
|
/*
|
|
* Restore work_mem.
|
|
*/
|
|
AtEOXact_GUC(true, save_nestlevel);
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* Local functions below
|
|
* ----------
|
|
*/
|
|
|
|
|
|
/*
|
|
* quoteOneName --- safely quote a single SQL name
|
|
*
|
|
* buffer must be MAX_QUOTED_NAME_LEN long (includes room for \0)
|
|
*/
|
|
static void
|
|
quoteOneName(char *buffer, const char *name)
|
|
{
|
|
/* Rather than trying to be smart, just always quote it. */
|
|
*buffer++ = '"';
|
|
while (*name)
|
|
{
|
|
if (*name == '"')
|
|
*buffer++ = '"';
|
|
*buffer++ = *name++;
|
|
}
|
|
*buffer++ = '"';
|
|
*buffer = '\0';
|
|
}
|
|
|
|
/*
|
|
* quoteRelationName --- safely quote a fully qualified relation name
|
|
*
|
|
* buffer must be MAX_QUOTED_REL_NAME_LEN long (includes room for \0)
|
|
*/
|
|
static void
|
|
quoteRelationName(char *buffer, Relation rel)
|
|
{
|
|
quoteOneName(buffer, get_namespace_name(RelationGetNamespace(rel)));
|
|
buffer += strlen(buffer);
|
|
*buffer++ = '.';
|
|
quoteOneName(buffer, RelationGetRelationName(rel));
|
|
}
|
|
|
|
/*
|
|
* ri_GenerateQual --- generate a WHERE clause equating two variables
|
|
*
|
|
* This basically appends " sep leftop op rightop" to buf, adding casts
|
|
* and schema qualification as needed to ensure that the parser will select
|
|
* the operator we specify. leftop and rightop should be parenthesized
|
|
* if they aren't variables or parameters.
|
|
*/
|
|
static void
|
|
ri_GenerateQual(StringInfo buf,
|
|
const char *sep,
|
|
const char *leftop, Oid leftoptype,
|
|
Oid opoid,
|
|
const char *rightop, Oid rightoptype)
|
|
{
|
|
appendStringInfo(buf, " %s ", sep);
|
|
generate_operator_clause(buf, leftop, leftoptype, opoid,
|
|
rightop, rightoptype);
|
|
}
|
|
|
|
/*
|
|
* ri_GenerateQualCollation --- add a COLLATE spec to a WHERE clause
|
|
*
|
|
* At present, we intentionally do not use this function for RI queries that
|
|
* compare a variable to a $n parameter. Since parameter symbols always have
|
|
* default collation, the effect will be to use the variable's collation.
|
|
* Now that is only strictly correct when testing the referenced column, since
|
|
* the SQL standard specifies that RI comparisons should use the referenced
|
|
* column's collation. However, so long as all collations have the same
|
|
* notion of equality (which they do, because texteq reduces to bitwise
|
|
* equality), there's no visible semantic impact from using the referencing
|
|
* column's collation when testing it, and this is a good thing to do because
|
|
* it lets us use a normal index on the referencing column. However, we do
|
|
* have to use this function when directly comparing the referencing and
|
|
* referenced columns, if they are of different collations; else the parser
|
|
* will fail to resolve the collation to use.
|
|
*/
|
|
static void
|
|
ri_GenerateQualCollation(StringInfo buf, Oid collation)
|
|
{
|
|
HeapTuple tp;
|
|
Form_pg_collation colltup;
|
|
char *collname;
|
|
char onename[MAX_QUOTED_NAME_LEN];
|
|
|
|
/* Nothing to do if it's a noncollatable data type */
|
|
if (!OidIsValid(collation))
|
|
return;
|
|
|
|
tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
|
|
if (!HeapTupleIsValid(tp))
|
|
elog(ERROR, "cache lookup failed for collation %u", collation);
|
|
colltup = (Form_pg_collation) GETSTRUCT(tp);
|
|
collname = NameStr(colltup->collname);
|
|
|
|
/*
|
|
* We qualify the name always, for simplicity and to ensure the query is
|
|
* not search-path-dependent.
|
|
*/
|
|
quoteOneName(onename, get_namespace_name(colltup->collnamespace));
|
|
appendStringInfo(buf, " COLLATE %s", onename);
|
|
quoteOneName(onename, collname);
|
|
appendStringInfo(buf, ".%s", onename);
|
|
|
|
ReleaseSysCache(tp);
|
|
}
|
|
|
|
/* ----------
|
|
* ri_BuildQueryKey -
|
|
*
|
|
* Construct a hashtable key for a prepared SPI plan of an FK constraint.
|
|
*
|
|
* key: output argument, *key is filled in based on the other arguments
|
|
* riinfo: info from pg_constraint entry
|
|
* constr_queryno: an internal number identifying the query type
|
|
* (see RI_PLAN_XXX constants at head of file)
|
|
* ----------
|
|
*/
|
|
static void
|
|
ri_BuildQueryKey(RI_QueryKey *key, const RI_ConstraintInfo *riinfo,
|
|
int32 constr_queryno)
|
|
{
|
|
/*
|
|
* We assume struct RI_QueryKey contains no padding bytes, else we'd need
|
|
* to use memset to clear them.
|
|
*/
|
|
key->constr_id = riinfo->constraint_id;
|
|
key->constr_queryno = constr_queryno;
|
|
}
|
|
|
|
/*
|
|
* Check that RI trigger function was called in expected context
|
|
*/
|
|
static void
|
|
ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
|
|
{
|
|
TriggerData *trigdata = (TriggerData *) fcinfo->context;
|
|
|
|
if (!CALLED_AS_TRIGGER(fcinfo))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
|
|
errmsg("function \"%s\" was not called by trigger manager", funcname)));
|
|
|
|
/*
|
|
* Check proper event
|
|
*/
|
|
if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
|
|
!TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
|
|
errmsg("function \"%s\" must be fired AFTER ROW", funcname)));
|
|
|
|
switch (tgkind)
|
|
{
|
|
case RI_TRIGTYPE_INSERT:
|
|
if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
|
|
errmsg("function \"%s\" must be fired for INSERT", funcname)));
|
|
break;
|
|
case RI_TRIGTYPE_UPDATE:
|
|
if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
|
|
errmsg("function \"%s\" must be fired for UPDATE", funcname)));
|
|
break;
|
|
case RI_TRIGTYPE_DELETE:
|
|
if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
|
|
errmsg("function \"%s\" must be fired for DELETE", funcname)));
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Fetch the RI_ConstraintInfo struct for the trigger's FK constraint.
|
|
*/
|
|
static const RI_ConstraintInfo *
|
|
ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
|
|
{
|
|
Oid constraintOid = trigger->tgconstraint;
|
|
const RI_ConstraintInfo *riinfo;
|
|
|
|
/*
|
|
* Check that the FK constraint's OID is available; it might not be if
|
|
* we've been invoked via an ordinary trigger or an old-style "constraint
|
|
* trigger".
|
|
*/
|
|
if (!OidIsValid(constraintOid))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
|
|
errmsg("no pg_constraint entry for trigger \"%s\" on table \"%s\"",
|
|
trigger->tgname, RelationGetRelationName(trig_rel)),
|
|
errhint("Remove this referential integrity trigger and its mates, then do ALTER TABLE ADD CONSTRAINT.")));
|
|
|
|
/* Find or create a hashtable entry for the constraint */
|
|
riinfo = ri_LoadConstraintInfo(constraintOid);
|
|
|
|
/* Do some easy cross-checks against the trigger call data */
|
|
if (rel_is_pk)
|
|
{
|
|
if (riinfo->fk_relid != trigger->tgconstrrelid ||
|
|
riinfo->pk_relid != RelationGetRelid(trig_rel))
|
|
elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
|
|
trigger->tgname, RelationGetRelationName(trig_rel));
|
|
}
|
|
else
|
|
{
|
|
if (riinfo->fk_relid != RelationGetRelid(trig_rel) ||
|
|
riinfo->pk_relid != trigger->tgconstrrelid)
|
|
elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
|
|
trigger->tgname, RelationGetRelationName(trig_rel));
|
|
}
|
|
|
|
return riinfo;
|
|
}
|
|
|
|
/*
|
|
* Fetch or create the RI_ConstraintInfo struct for an FK constraint.
|
|
*/
|
|
static const RI_ConstraintInfo *
|
|
ri_LoadConstraintInfo(Oid constraintOid)
|
|
{
|
|
RI_ConstraintInfo *riinfo;
|
|
bool found;
|
|
HeapTuple tup;
|
|
Form_pg_constraint conForm;
|
|
Datum adatum;
|
|
bool isNull;
|
|
ArrayType *arr;
|
|
int numkeys;
|
|
|
|
/*
|
|
* On the first call initialize the hashtable
|
|
*/
|
|
if (!ri_constraint_cache)
|
|
ri_InitHashTables();
|
|
|
|
/*
|
|
* Find or create a hash entry. If we find a valid one, just return it.
|
|
*/
|
|
riinfo = (RI_ConstraintInfo *) hash_search(ri_constraint_cache,
|
|
(void *) &constraintOid,
|
|
HASH_ENTER, &found);
|
|
if (!found)
|
|
riinfo->valid = false;
|
|
else if (riinfo->valid)
|
|
return riinfo;
|
|
|
|
/*
|
|
* Fetch the pg_constraint row so we can fill in the entry.
|
|
*/
|
|
tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
|
|
if (!HeapTupleIsValid(tup)) /* should not happen */
|
|
elog(ERROR, "cache lookup failed for constraint %u", constraintOid);
|
|
conForm = (Form_pg_constraint) GETSTRUCT(tup);
|
|
|
|
if (conForm->contype != CONSTRAINT_FOREIGN) /* should not happen */
|
|
elog(ERROR, "constraint %u is not a foreign key constraint",
|
|
constraintOid);
|
|
|
|
/* And extract data */
|
|
Assert(riinfo->constraint_id == constraintOid);
|
|
riinfo->oidHashValue = GetSysCacheHashValue1(CONSTROID,
|
|
ObjectIdGetDatum(constraintOid));
|
|
memcpy(&riinfo->conname, &conForm->conname, sizeof(NameData));
|
|
riinfo->pk_relid = conForm->confrelid;
|
|
riinfo->fk_relid = conForm->conrelid;
|
|
riinfo->confupdtype = conForm->confupdtype;
|
|
riinfo->confdeltype = conForm->confdeltype;
|
|
riinfo->confmatchtype = conForm->confmatchtype;
|
|
|
|
/*
|
|
* We expect the arrays to be 1-D arrays of the right types; verify that.
|
|
* We don't need to use deconstruct_array() since the array data is just
|
|
* going to look like a C array of values.
|
|
*/
|
|
adatum = SysCacheGetAttr(CONSTROID, tup,
|
|
Anum_pg_constraint_conkey, &isNull);
|
|
if (isNull)
|
|
elog(ERROR, "null conkey for constraint %u", constraintOid);
|
|
arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
|
|
if (ARR_NDIM(arr) != 1 ||
|
|
ARR_HASNULL(arr) ||
|
|
ARR_ELEMTYPE(arr) != INT2OID)
|
|
elog(ERROR, "conkey is not a 1-D smallint array");
|
|
numkeys = ARR_DIMS(arr)[0];
|
|
if (numkeys <= 0 || numkeys > RI_MAX_NUMKEYS)
|
|
elog(ERROR, "foreign key constraint cannot have %d columns", numkeys);
|
|
riinfo->nkeys = numkeys;
|
|
memcpy(riinfo->fk_attnums, ARR_DATA_PTR(arr), numkeys * sizeof(int16));
|
|
if ((Pointer) arr != DatumGetPointer(adatum))
|
|
pfree(arr); /* free de-toasted copy, if any */
|
|
|
|
adatum = SysCacheGetAttr(CONSTROID, tup,
|
|
Anum_pg_constraint_confkey, &isNull);
|
|
if (isNull)
|
|
elog(ERROR, "null confkey for constraint %u", constraintOid);
|
|
arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
|
|
if (ARR_NDIM(arr) != 1 ||
|
|
ARR_DIMS(arr)[0] != numkeys ||
|
|
ARR_HASNULL(arr) ||
|
|
ARR_ELEMTYPE(arr) != INT2OID)
|
|
elog(ERROR, "confkey is not a 1-D smallint array");
|
|
memcpy(riinfo->pk_attnums, ARR_DATA_PTR(arr), numkeys * sizeof(int16));
|
|
if ((Pointer) arr != DatumGetPointer(adatum))
|
|
pfree(arr); /* free de-toasted copy, if any */
|
|
|
|
adatum = SysCacheGetAttr(CONSTROID, tup,
|
|
Anum_pg_constraint_conpfeqop, &isNull);
|
|
if (isNull)
|
|
elog(ERROR, "null conpfeqop for constraint %u", constraintOid);
|
|
arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
|
|
/* see TryReuseForeignKey if you change the test below */
|
|
if (ARR_NDIM(arr) != 1 ||
|
|
ARR_DIMS(arr)[0] != numkeys ||
|
|
ARR_HASNULL(arr) ||
|
|
ARR_ELEMTYPE(arr) != OIDOID)
|
|
elog(ERROR, "conpfeqop is not a 1-D Oid array");
|
|
memcpy(riinfo->pf_eq_oprs, ARR_DATA_PTR(arr), numkeys * sizeof(Oid));
|
|
if ((Pointer) arr != DatumGetPointer(adatum))
|
|
pfree(arr); /* free de-toasted copy, if any */
|
|
|
|
adatum = SysCacheGetAttr(CONSTROID, tup,
|
|
Anum_pg_constraint_conppeqop, &isNull);
|
|
if (isNull)
|
|
elog(ERROR, "null conppeqop for constraint %u", constraintOid);
|
|
arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
|
|
if (ARR_NDIM(arr) != 1 ||
|
|
ARR_DIMS(arr)[0] != numkeys ||
|
|
ARR_HASNULL(arr) ||
|
|
ARR_ELEMTYPE(arr) != OIDOID)
|
|
elog(ERROR, "conppeqop is not a 1-D Oid array");
|
|
memcpy(riinfo->pp_eq_oprs, ARR_DATA_PTR(arr), numkeys * sizeof(Oid));
|
|
if ((Pointer) arr != DatumGetPointer(adatum))
|
|
pfree(arr); /* free de-toasted copy, if any */
|
|
|
|
adatum = SysCacheGetAttr(CONSTROID, tup,
|
|
Anum_pg_constraint_conffeqop, &isNull);
|
|
if (isNull)
|
|
elog(ERROR, "null conffeqop for constraint %u", constraintOid);
|
|
arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
|
|
if (ARR_NDIM(arr) != 1 ||
|
|
ARR_DIMS(arr)[0] != numkeys ||
|
|
ARR_HASNULL(arr) ||
|
|
ARR_ELEMTYPE(arr) != OIDOID)
|
|
elog(ERROR, "conffeqop is not a 1-D Oid array");
|
|
memcpy(riinfo->ff_eq_oprs, ARR_DATA_PTR(arr), numkeys * sizeof(Oid));
|
|
if ((Pointer) arr != DatumGetPointer(adatum))
|
|
pfree(arr); /* free de-toasted copy, if any */
|
|
|
|
ReleaseSysCache(tup);
|
|
|
|
/*
|
|
* For efficient processing of invalidation messages below, we keep a
|
|
* doubly-linked list, and a count, of all currently valid entries.
|
|
*/
|
|
dlist_push_tail(&ri_constraint_cache_valid_list, &riinfo->valid_link);
|
|
ri_constraint_cache_valid_count++;
|
|
|
|
riinfo->valid = true;
|
|
|
|
return riinfo;
|
|
}
|
|
|
|
/*
|
|
* Callback for pg_constraint inval events
|
|
*
|
|
* While most syscache callbacks just flush all their entries, pg_constraint
|
|
* gets enough update traffic that it's probably worth being smarter.
|
|
* Invalidate any ri_constraint_cache entry associated with the syscache
|
|
* entry with the specified hash value, or all entries if hashvalue == 0.
|
|
*
|
|
* Note: at the time a cache invalidation message is processed there may be
|
|
* active references to the cache. Because of this we never remove entries
|
|
* from the cache, but only mark them invalid, which is harmless to active
|
|
* uses. (Any query using an entry should hold a lock sufficient to keep that
|
|
* data from changing under it --- but we may get cache flushes anyway.)
|
|
*/
|
|
static void
|
|
InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue)
|
|
{
|
|
dlist_mutable_iter iter;
|
|
|
|
Assert(ri_constraint_cache != NULL);
|
|
|
|
/*
|
|
* If the list of currently valid entries gets excessively large, we mark
|
|
* them all invalid so we can empty the list. This arrangement avoids
|
|
* O(N^2) behavior in situations where a session touches many foreign keys
|
|
* and also does many ALTER TABLEs, such as a restore from pg_dump.
|
|
*/
|
|
if (ri_constraint_cache_valid_count > 1000)
|
|
hashvalue = 0; /* pretend it's a cache reset */
|
|
|
|
dlist_foreach_modify(iter, &ri_constraint_cache_valid_list)
|
|
{
|
|
RI_ConstraintInfo *riinfo = dlist_container(RI_ConstraintInfo,
|
|
valid_link, iter.cur);
|
|
|
|
if (hashvalue == 0 || riinfo->oidHashValue == hashvalue)
|
|
{
|
|
riinfo->valid = false;
|
|
/* Remove invalidated entries from the list, too */
|
|
dlist_delete(iter.cur);
|
|
ri_constraint_cache_valid_count--;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Prepare execution plan for a query to enforce an RI restriction
|
|
*
|
|
* If cache_plan is true, the plan is saved into our plan hashtable
|
|
* so that we don't need to plan it again.
|
|
*/
|
|
static SPIPlanPtr
|
|
ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
|
|
RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel,
|
|
bool cache_plan)
|
|
{
|
|
SPIPlanPtr qplan;
|
|
Relation query_rel;
|
|
Oid save_userid;
|
|
int save_sec_context;
|
|
|
|
/*
|
|
* Use the query type code to determine whether the query is run against
|
|
* the PK or FK table; we'll do the check as that table's owner
|
|
*/
|
|
if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
|
|
query_rel = pk_rel;
|
|
else
|
|
query_rel = fk_rel;
|
|
|
|
/* Switch to proper UID to perform check as */
|
|
GetUserIdAndSecContext(&save_userid, &save_sec_context);
|
|
SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
|
|
save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
|
|
SECURITY_NOFORCE_RLS);
|
|
|
|
/* Create the plan */
|
|
qplan = SPI_prepare(querystr, nargs, argtypes);
|
|
|
|
if (qplan == NULL)
|
|
elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), querystr);
|
|
|
|
/* Restore UID and security context */
|
|
SetUserIdAndSecContext(save_userid, save_sec_context);
|
|
|
|
/* Save the plan if requested */
|
|
if (cache_plan)
|
|
{
|
|
SPI_keepplan(qplan);
|
|
ri_HashPreparedPlan(qkey, qplan);
|
|
}
|
|
|
|
return qplan;
|
|
}
|
|
|
|
/*
|
|
* Perform a query to enforce an RI restriction
|
|
*/
|
|
static bool
|
|
ri_PerformCheck(const RI_ConstraintInfo *riinfo,
|
|
RI_QueryKey *qkey, SPIPlanPtr qplan,
|
|
Relation fk_rel, Relation pk_rel,
|
|
HeapTuple old_tuple, HeapTuple new_tuple,
|
|
bool detectNewRows, int expect_OK)
|
|
{
|
|
Relation query_rel,
|
|
source_rel;
|
|
bool source_is_pk;
|
|
Snapshot test_snapshot;
|
|
Snapshot crosscheck_snapshot;
|
|
int limit;
|
|
int spi_result;
|
|
Oid save_userid;
|
|
int save_sec_context;
|
|
Datum vals[RI_MAX_NUMKEYS * 2];
|
|
char nulls[RI_MAX_NUMKEYS * 2];
|
|
|
|
/*
|
|
* Use the query type code to determine whether the query is run against
|
|
* the PK or FK table; we'll do the check as that table's owner
|
|
*/
|
|
if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
|
|
query_rel = pk_rel;
|
|
else
|
|
query_rel = fk_rel;
|
|
|
|
/*
|
|
* The values for the query are taken from the table on which the trigger
|
|
* is called - it is normally the other one with respect to query_rel. An
|
|
* exception is ri_Check_Pk_Match(), which uses the PK table for both (and
|
|
* sets queryno to RI_PLAN_CHECK_LOOKUPPK_FROM_PK). We might eventually
|
|
* need some less klugy way to determine this.
|
|
*/
|
|
if (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK)
|
|
{
|
|
source_rel = fk_rel;
|
|
source_is_pk = false;
|
|
}
|
|
else
|
|
{
|
|
source_rel = pk_rel;
|
|
source_is_pk = true;
|
|
}
|
|
|
|
/* Extract the parameters to be passed into the query */
|
|
if (new_tuple)
|
|
{
|
|
ri_ExtractValues(source_rel, new_tuple, riinfo, source_is_pk,
|
|
vals, nulls);
|
|
if (old_tuple)
|
|
ri_ExtractValues(source_rel, old_tuple, riinfo, source_is_pk,
|
|
vals + riinfo->nkeys, nulls + riinfo->nkeys);
|
|
}
|
|
else
|
|
{
|
|
ri_ExtractValues(source_rel, old_tuple, riinfo, source_is_pk,
|
|
vals, nulls);
|
|
}
|
|
|
|
/*
|
|
* In READ COMMITTED mode, we just need to use an up-to-date regular
|
|
* snapshot, and we will see all rows that could be interesting. But in
|
|
* transaction-snapshot mode, we can't change the transaction snapshot. If
|
|
* the caller passes detectNewRows == false then it's okay to do the query
|
|
* with the transaction snapshot; otherwise we use a current snapshot, and
|
|
* tell the executor to error out if it finds any rows under the current
|
|
* snapshot that wouldn't be visible per the transaction snapshot. Note
|
|
* that SPI_execute_snapshot will register the snapshots, so we don't need
|
|
* to bother here.
|
|
*/
|
|
if (IsolationUsesXactSnapshot() && detectNewRows)
|
|
{
|
|
CommandCounterIncrement(); /* be sure all my own work is visible */
|
|
test_snapshot = GetLatestSnapshot();
|
|
crosscheck_snapshot = GetTransactionSnapshot();
|
|
}
|
|
else
|
|
{
|
|
/* the default SPI behavior is okay */
|
|
test_snapshot = InvalidSnapshot;
|
|
crosscheck_snapshot = InvalidSnapshot;
|
|
}
|
|
|
|
/*
|
|
* If this is a select query (e.g., for a 'no action' or 'restrict'
|
|
* trigger), we only need to see if there is a single row in the table,
|
|
* matching the key. Otherwise, limit = 0 - because we want the query to
|
|
* affect ALL the matching rows.
|
|
*/
|
|
limit = (expect_OK == SPI_OK_SELECT) ? 1 : 0;
|
|
|
|
/* Switch to proper UID to perform check as */
|
|
GetUserIdAndSecContext(&save_userid, &save_sec_context);
|
|
SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
|
|
save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
|
|
SECURITY_NOFORCE_RLS);
|
|
|
|
/* Finally we can run the query. */
|
|
spi_result = SPI_execute_snapshot(qplan,
|
|
vals, nulls,
|
|
test_snapshot, crosscheck_snapshot,
|
|
false, false, limit);
|
|
|
|
/* Restore UID and security context */
|
|
SetUserIdAndSecContext(save_userid, save_sec_context);
|
|
|
|
/* Check result */
|
|
if (spi_result < 0)
|
|
elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
|
|
|
|
if (expect_OK >= 0 && spi_result != expect_OK)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INTERNAL_ERROR),
|
|
errmsg("referential integrity query on \"%s\" from constraint \"%s\" on \"%s\" gave unexpected result",
|
|
RelationGetRelationName(pk_rel),
|
|
NameStr(riinfo->conname),
|
|
RelationGetRelationName(fk_rel)),
|
|
errhint("This is most likely due to a rule having rewritten the query.")));
|
|
|
|
/* XXX wouldn't it be clearer to do this part at the caller? */
|
|
if (qkey->constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK &&
|
|
expect_OK == SPI_OK_SELECT &&
|
|
(SPI_processed == 0) == (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK))
|
|
ri_ReportViolation(riinfo,
|
|
pk_rel, fk_rel,
|
|
new_tuple ? new_tuple : old_tuple,
|
|
NULL,
|
|
qkey->constr_queryno);
|
|
|
|
return SPI_processed != 0;
|
|
}
|
|
|
|
/*
|
|
* Extract fields from a tuple into Datum/nulls arrays
|
|
*/
|
|
static void
|
|
ri_ExtractValues(Relation rel, HeapTuple tup,
|
|
const RI_ConstraintInfo *riinfo, bool rel_is_pk,
|
|
Datum *vals, char *nulls)
|
|
{
|
|
TupleDesc tupdesc = rel->rd_att;
|
|
const int16 *attnums;
|
|
int i;
|
|
bool isnull;
|
|
|
|
if (rel_is_pk)
|
|
attnums = riinfo->pk_attnums;
|
|
else
|
|
attnums = riinfo->fk_attnums;
|
|
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
vals[i] = heap_getattr(tup, attnums[i], tupdesc,
|
|
&isnull);
|
|
nulls[i] = isnull ? 'n' : ' ';
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Produce an error report
|
|
*
|
|
* If the failed constraint was on insert/update to the FK table,
|
|
* we want the key names and values extracted from there, and the error
|
|
* message to look like 'key blah is not present in PK'.
|
|
* Otherwise, the attr names and values come from the PK table and the
|
|
* message looks like 'key blah is still referenced from FK'.
|
|
*/
|
|
static void
|
|
ri_ReportViolation(const RI_ConstraintInfo *riinfo,
|
|
Relation pk_rel, Relation fk_rel,
|
|
HeapTuple violator, TupleDesc tupdesc,
|
|
int queryno)
|
|
{
|
|
StringInfoData key_names;
|
|
StringInfoData key_values;
|
|
bool onfk;
|
|
const int16 *attnums;
|
|
int idx;
|
|
Oid rel_oid;
|
|
AclResult aclresult;
|
|
bool has_perm = true;
|
|
|
|
/*
|
|
* Determine which relation to complain about. If tupdesc wasn't passed
|
|
* by caller, assume the violator tuple came from there.
|
|
*/
|
|
onfk = (queryno == RI_PLAN_CHECK_LOOKUPPK);
|
|
if (onfk)
|
|
{
|
|
attnums = riinfo->fk_attnums;
|
|
rel_oid = fk_rel->rd_id;
|
|
if (tupdesc == NULL)
|
|
tupdesc = fk_rel->rd_att;
|
|
}
|
|
else
|
|
{
|
|
attnums = riinfo->pk_attnums;
|
|
rel_oid = pk_rel->rd_id;
|
|
if (tupdesc == NULL)
|
|
tupdesc = pk_rel->rd_att;
|
|
}
|
|
|
|
/*
|
|
* Check permissions- if the user does not have access to view the data in
|
|
* any of the key columns then we don't include the errdetail() below.
|
|
*
|
|
* Check if RLS is enabled on the relation first. If so, we don't return
|
|
* any specifics to avoid leaking data.
|
|
*
|
|
* Check table-level permissions next and, failing that, column-level
|
|
* privileges.
|
|
*/
|
|
|
|
if (check_enable_rls(rel_oid, InvalidOid, true) != RLS_ENABLED)
|
|
{
|
|
aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
|
|
if (aclresult != ACLCHECK_OK)
|
|
{
|
|
/* Try for column-level permissions */
|
|
for (idx = 0; idx < riinfo->nkeys; idx++)
|
|
{
|
|
aclresult = pg_attribute_aclcheck(rel_oid, attnums[idx],
|
|
GetUserId(),
|
|
ACL_SELECT);
|
|
|
|
/* No access to the key */
|
|
if (aclresult != ACLCHECK_OK)
|
|
{
|
|
has_perm = false;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else
|
|
has_perm = false;
|
|
|
|
if (has_perm)
|
|
{
|
|
/* Get printable versions of the keys involved */
|
|
initStringInfo(&key_names);
|
|
initStringInfo(&key_values);
|
|
for (idx = 0; idx < riinfo->nkeys; idx++)
|
|
{
|
|
int fnum = attnums[idx];
|
|
char *name,
|
|
*val;
|
|
|
|
name = SPI_fname(tupdesc, fnum);
|
|
val = SPI_getvalue(violator, tupdesc, fnum);
|
|
if (!val)
|
|
val = "null";
|
|
|
|
if (idx > 0)
|
|
{
|
|
appendStringInfoString(&key_names, ", ");
|
|
appendStringInfoString(&key_values, ", ");
|
|
}
|
|
appendStringInfoString(&key_names, name);
|
|
appendStringInfoString(&key_values, val);
|
|
}
|
|
}
|
|
|
|
if (onfk)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
|
|
errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
|
|
RelationGetRelationName(fk_rel),
|
|
NameStr(riinfo->conname)),
|
|
has_perm ?
|
|
errdetail("Key (%s)=(%s) is not present in table \"%s\".",
|
|
key_names.data, key_values.data,
|
|
RelationGetRelationName(pk_rel)) :
|
|
errdetail("Key is not present in table \"%s\".",
|
|
RelationGetRelationName(pk_rel)),
|
|
errtableconstraint(fk_rel, NameStr(riinfo->conname))));
|
|
else
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
|
|
errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
|
|
RelationGetRelationName(pk_rel),
|
|
NameStr(riinfo->conname),
|
|
RelationGetRelationName(fk_rel)),
|
|
has_perm ?
|
|
errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
|
|
key_names.data, key_values.data,
|
|
RelationGetRelationName(fk_rel)) :
|
|
errdetail("Key is still referenced from table \"%s\".",
|
|
RelationGetRelationName(fk_rel)),
|
|
errtableconstraint(fk_rel, NameStr(riinfo->conname))));
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* ri_NullCheck -
|
|
*
|
|
* Determine the NULL state of all key values in a tuple
|
|
*
|
|
* Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
|
|
* ----------
|
|
*/
|
|
static int
|
|
ri_NullCheck(TupleDesc tupDesc,
|
|
HeapTuple tup,
|
|
const RI_ConstraintInfo *riinfo, bool rel_is_pk)
|
|
{
|
|
const int16 *attnums;
|
|
int i;
|
|
bool allnull = true;
|
|
bool nonenull = true;
|
|
|
|
if (rel_is_pk)
|
|
attnums = riinfo->pk_attnums;
|
|
else
|
|
attnums = riinfo->fk_attnums;
|
|
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
if (heap_attisnull(tup, attnums[i], tupDesc))
|
|
nonenull = false;
|
|
else
|
|
allnull = false;
|
|
}
|
|
|
|
if (allnull)
|
|
return RI_KEYS_ALL_NULL;
|
|
|
|
if (nonenull)
|
|
return RI_KEYS_NONE_NULL;
|
|
|
|
return RI_KEYS_SOME_NULL;
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* ri_InitHashTables -
|
|
*
|
|
* Initialize our internal hash tables.
|
|
* ----------
|
|
*/
|
|
static void
|
|
ri_InitHashTables(void)
|
|
{
|
|
HASHCTL ctl;
|
|
|
|
memset(&ctl, 0, sizeof(ctl));
|
|
ctl.keysize = sizeof(Oid);
|
|
ctl.entrysize = sizeof(RI_ConstraintInfo);
|
|
ri_constraint_cache = hash_create("RI constraint cache",
|
|
RI_INIT_CONSTRAINTHASHSIZE,
|
|
&ctl, HASH_ELEM | HASH_BLOBS);
|
|
|
|
/* Arrange to flush cache on pg_constraint changes */
|
|
CacheRegisterSyscacheCallback(CONSTROID,
|
|
InvalidateConstraintCacheCallBack,
|
|
(Datum) 0);
|
|
|
|
memset(&ctl, 0, sizeof(ctl));
|
|
ctl.keysize = sizeof(RI_QueryKey);
|
|
ctl.entrysize = sizeof(RI_QueryHashEntry);
|
|
ri_query_cache = hash_create("RI query cache",
|
|
RI_INIT_QUERYHASHSIZE,
|
|
&ctl, HASH_ELEM | HASH_BLOBS);
|
|
|
|
memset(&ctl, 0, sizeof(ctl));
|
|
ctl.keysize = sizeof(RI_CompareKey);
|
|
ctl.entrysize = sizeof(RI_CompareHashEntry);
|
|
ri_compare_cache = hash_create("RI compare cache",
|
|
RI_INIT_QUERYHASHSIZE,
|
|
&ctl, HASH_ELEM | HASH_BLOBS);
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* ri_FetchPreparedPlan -
|
|
*
|
|
* Lookup for a query key in our private hash table of prepared
|
|
* and saved SPI execution plans. Return the plan if found or NULL.
|
|
* ----------
|
|
*/
|
|
static SPIPlanPtr
|
|
ri_FetchPreparedPlan(RI_QueryKey *key)
|
|
{
|
|
RI_QueryHashEntry *entry;
|
|
SPIPlanPtr plan;
|
|
|
|
/*
|
|
* On the first call initialize the hashtable
|
|
*/
|
|
if (!ri_query_cache)
|
|
ri_InitHashTables();
|
|
|
|
/*
|
|
* Lookup for the key
|
|
*/
|
|
entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
|
|
(void *) key,
|
|
HASH_FIND, NULL);
|
|
if (entry == NULL)
|
|
return NULL;
|
|
|
|
/*
|
|
* Check whether the plan is still valid. If it isn't, we don't want to
|
|
* simply rely on plancache.c to regenerate it; rather we should start
|
|
* from scratch and rebuild the query text too. This is to cover cases
|
|
* such as table/column renames. We depend on the plancache machinery to
|
|
* detect possible invalidations, though.
|
|
*
|
|
* CAUTION: this check is only trustworthy if the caller has already
|
|
* locked both FK and PK rels.
|
|
*/
|
|
plan = entry->plan;
|
|
if (plan && SPI_plan_is_valid(plan))
|
|
return plan;
|
|
|
|
/*
|
|
* Otherwise we might as well flush the cached plan now, to free a little
|
|
* memory space before we make a new one.
|
|
*/
|
|
entry->plan = NULL;
|
|
if (plan)
|
|
SPI_freeplan(plan);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* ri_HashPreparedPlan -
|
|
*
|
|
* Add another plan to our private SPI query plan hashtable.
|
|
* ----------
|
|
*/
|
|
static void
|
|
ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
|
|
{
|
|
RI_QueryHashEntry *entry;
|
|
bool found;
|
|
|
|
/*
|
|
* On the first call initialize the hashtable
|
|
*/
|
|
if (!ri_query_cache)
|
|
ri_InitHashTables();
|
|
|
|
/*
|
|
* Add the new plan. We might be overwriting an entry previously found
|
|
* invalid by ri_FetchPreparedPlan.
|
|
*/
|
|
entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
|
|
(void *) key,
|
|
HASH_ENTER, &found);
|
|
Assert(!found || entry->plan == NULL);
|
|
entry->plan = plan;
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* ri_KeysEqual -
|
|
*
|
|
* Check if all key values in OLD and NEW are equal.
|
|
*
|
|
* Note: at some point we might wish to redefine this as checking for
|
|
* "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
|
|
* considered equal. Currently there is no need since all callers have
|
|
* previously found at least one of the rows to contain no nulls.
|
|
* ----------
|
|
*/
|
|
static bool
|
|
ri_KeysEqual(Relation rel, HeapTuple oldtup, HeapTuple newtup,
|
|
const RI_ConstraintInfo *riinfo, bool rel_is_pk)
|
|
{
|
|
TupleDesc tupdesc = RelationGetDescr(rel);
|
|
const int16 *attnums;
|
|
const Oid *eq_oprs;
|
|
int i;
|
|
|
|
if (rel_is_pk)
|
|
{
|
|
attnums = riinfo->pk_attnums;
|
|
eq_oprs = riinfo->pp_eq_oprs;
|
|
}
|
|
else
|
|
{
|
|
attnums = riinfo->fk_attnums;
|
|
eq_oprs = riinfo->ff_eq_oprs;
|
|
}
|
|
|
|
for (i = 0; i < riinfo->nkeys; i++)
|
|
{
|
|
Datum oldvalue;
|
|
Datum newvalue;
|
|
bool isnull;
|
|
|
|
/*
|
|
* Get one attribute's oldvalue. If it is NULL - they're not equal.
|
|
*/
|
|
oldvalue = heap_getattr(oldtup, attnums[i], tupdesc, &isnull);
|
|
if (isnull)
|
|
return false;
|
|
|
|
/*
|
|
* Get one attribute's newvalue. If it is NULL - they're not equal.
|
|
*/
|
|
newvalue = heap_getattr(newtup, attnums[i], tupdesc, &isnull);
|
|
if (isnull)
|
|
return false;
|
|
|
|
/*
|
|
* Compare them with the appropriate equality operator.
|
|
*/
|
|
if (!ri_AttributesEqual(eq_oprs[i], RIAttType(rel, attnums[i]),
|
|
oldvalue, newvalue))
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/* ----------
|
|
* ri_AttributesEqual -
|
|
*
|
|
* Call the appropriate equality comparison operator for two values.
|
|
*
|
|
* NB: we have already checked that neither value is null.
|
|
* ----------
|
|
*/
|
|
static bool
|
|
ri_AttributesEqual(Oid eq_opr, Oid typeid,
|
|
Datum oldvalue, Datum newvalue)
|
|
{
|
|
RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
|
|
|
|
/* Do we need to cast the values? */
|
|
if (OidIsValid(entry->cast_func_finfo.fn_oid))
|
|
{
|
|
oldvalue = FunctionCall3(&entry->cast_func_finfo,
|
|
oldvalue,
|
|
Int32GetDatum(-1), /* typmod */
|
|
BoolGetDatum(false)); /* implicit coercion */
|
|
newvalue = FunctionCall3(&entry->cast_func_finfo,
|
|
newvalue,
|
|
Int32GetDatum(-1), /* typmod */
|
|
BoolGetDatum(false)); /* implicit coercion */
|
|
}
|
|
|
|
/*
|
|
* Apply the comparison operator. We assume it doesn't care about
|
|
* collations.
|
|
*/
|
|
return DatumGetBool(FunctionCall2(&entry->eq_opr_finfo,
|
|
oldvalue, newvalue));
|
|
}
|
|
|
|
/* ----------
|
|
* ri_HashCompareOp -
|
|
*
|
|
* See if we know how to compare two values, and create a new hash entry
|
|
* if not.
|
|
* ----------
|
|
*/
|
|
static RI_CompareHashEntry *
|
|
ri_HashCompareOp(Oid eq_opr, Oid typeid)
|
|
{
|
|
RI_CompareKey key;
|
|
RI_CompareHashEntry *entry;
|
|
bool found;
|
|
|
|
/*
|
|
* On the first call initialize the hashtable
|
|
*/
|
|
if (!ri_compare_cache)
|
|
ri_InitHashTables();
|
|
|
|
/*
|
|
* Find or create a hash entry. Note we're assuming RI_CompareKey
|
|
* contains no struct padding.
|
|
*/
|
|
key.eq_opr = eq_opr;
|
|
key.typeid = typeid;
|
|
entry = (RI_CompareHashEntry *) hash_search(ri_compare_cache,
|
|
(void *) &key,
|
|
HASH_ENTER, &found);
|
|
if (!found)
|
|
entry->valid = false;
|
|
|
|
/*
|
|
* If not already initialized, do so. Since we'll keep this hash entry
|
|
* for the life of the backend, put any subsidiary info for the function
|
|
* cache structs into TopMemoryContext.
|
|
*/
|
|
if (!entry->valid)
|
|
{
|
|
Oid lefttype,
|
|
righttype,
|
|
castfunc;
|
|
CoercionPathType pathtype;
|
|
|
|
/* We always need to know how to call the equality operator */
|
|
fmgr_info_cxt(get_opcode(eq_opr), &entry->eq_opr_finfo,
|
|
TopMemoryContext);
|
|
|
|
/*
|
|
* If we chose to use a cast from FK to PK type, we may have to apply
|
|
* the cast function to get to the operator's input type.
|
|
*
|
|
* XXX eventually it would be good to support array-coercion cases
|
|
* here and in ri_AttributesEqual(). At the moment there is no point
|
|
* because cases involving nonidentical array types will be rejected
|
|
* at constraint creation time.
|
|
*
|
|
* XXX perhaps also consider supporting CoerceViaIO? No need at the
|
|
* moment since that will never be generated for implicit coercions.
|
|
*/
|
|
op_input_types(eq_opr, &lefttype, &righttype);
|
|
Assert(lefttype == righttype);
|
|
if (typeid == lefttype)
|
|
castfunc = InvalidOid; /* simplest case */
|
|
else
|
|
{
|
|
pathtype = find_coercion_pathway(lefttype, typeid,
|
|
COERCION_IMPLICIT,
|
|
&castfunc);
|
|
if (pathtype != COERCION_PATH_FUNC &&
|
|
pathtype != COERCION_PATH_RELABELTYPE)
|
|
{
|
|
/*
|
|
* The declared input type of the eq_opr might be a
|
|
* polymorphic type such as ANYARRAY or ANYENUM, or other
|
|
* special cases such as RECORD; find_coercion_pathway
|
|
* currently doesn't subsume these special cases.
|
|
*/
|
|
if (!IsBinaryCoercible(typeid, lefttype))
|
|
elog(ERROR, "no conversion function from %s to %s",
|
|
format_type_be(typeid),
|
|
format_type_be(lefttype));
|
|
}
|
|
}
|
|
if (OidIsValid(castfunc))
|
|
fmgr_info_cxt(castfunc, &entry->cast_func_finfo,
|
|
TopMemoryContext);
|
|
else
|
|
entry->cast_func_finfo.fn_oid = InvalidOid;
|
|
entry->valid = true;
|
|
}
|
|
|
|
return entry;
|
|
}
|
|
|
|
|
|
/*
|
|
* Given a trigger function OID, determine whether it is an RI trigger,
|
|
* and if so whether it is attached to PK or FK relation.
|
|
*/
|
|
int
|
|
RI_FKey_trigger_type(Oid tgfoid)
|
|
{
|
|
switch (tgfoid)
|
|
{
|
|
case F_RI_FKEY_CASCADE_DEL:
|
|
case F_RI_FKEY_CASCADE_UPD:
|
|
case F_RI_FKEY_RESTRICT_DEL:
|
|
case F_RI_FKEY_RESTRICT_UPD:
|
|
case F_RI_FKEY_SETNULL_DEL:
|
|
case F_RI_FKEY_SETNULL_UPD:
|
|
case F_RI_FKEY_SETDEFAULT_DEL:
|
|
case F_RI_FKEY_SETDEFAULT_UPD:
|
|
case F_RI_FKEY_NOACTION_DEL:
|
|
case F_RI_FKEY_NOACTION_UPD:
|
|
return RI_TRIGGER_PK;
|
|
|
|
case F_RI_FKEY_CHECK_INS:
|
|
case F_RI_FKEY_CHECK_UPD:
|
|
return RI_TRIGGER_FK;
|
|
}
|
|
|
|
return RI_TRIGGER_NONE;
|
|
}
|