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Diffstat (limited to 'src/backend/catalog/pg_constraint.c')
-rw-r--r--src/backend/catalog/pg_constraint.c254
1 files changed, 124 insertions, 130 deletions
diff --git a/src/backend/catalog/pg_constraint.c b/src/backend/catalog/pg_constraint.c
index ea844413608..6781b00c6e6 100644
--- a/src/backend/catalog/pg_constraint.c
+++ b/src/backend/catalog/pg_constraint.c
@@ -422,7 +422,7 @@ CloneForeignKeyConstraints(Oid parentId, Oid relationId, List **cloned)
ScanKeyInit(&key,
Anum_pg_constraint_conrelid, BTEqualStrategyNumber,
F_OIDEQ, ObjectIdGetDatum(parentId));
- scan = systable_beginscan(pg_constraint, ConstraintRelidIndexId, true,
+ scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
NULL, 1, &key);
while ((tuple = systable_getnext(scan)) != NULL)
@@ -632,17 +632,58 @@ CloneForeignKeyConstraints(Oid parentId, Oid relationId, List **cloned)
*/
bool
ConstraintNameIsUsed(ConstraintCategory conCat, Oid objId,
- Oid objNamespace, const char *conname)
+ const char *conname)
{
bool found;
Relation conDesc;
SysScanDesc conscan;
- ScanKeyData skey[2];
- HeapTuple tup;
+ ScanKeyData skey[3];
conDesc = heap_open(ConstraintRelationId, AccessShareLock);
- found = false;
+ ScanKeyInit(&skey[0],
+ Anum_pg_constraint_conrelid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum((conCat == CONSTRAINT_RELATION)
+ ? objId : InvalidOid));
+ ScanKeyInit(&skey[1],
+ Anum_pg_constraint_contypid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum((conCat == CONSTRAINT_DOMAIN)
+ ? objId : InvalidOid));
+ ScanKeyInit(&skey[2],
+ Anum_pg_constraint_conname,
+ BTEqualStrategyNumber, F_NAMEEQ,
+ CStringGetDatum(conname));
+
+ conscan = systable_beginscan(conDesc, ConstraintRelidTypidNameIndexId,
+ true, NULL, 3, skey);
+
+ /* There can be at most one matching row */
+ found = (HeapTupleIsValid(systable_getnext(conscan)));
+
+ systable_endscan(conscan);
+ heap_close(conDesc, AccessShareLock);
+
+ return found;
+}
+
+/*
+ * Does any constraint of the given name exist in the given namespace?
+ *
+ * This is used for code that wants to match ChooseConstraintName's rule
+ * that we should avoid autogenerating duplicate constraint names within a
+ * namespace.
+ */
+bool
+ConstraintNameExists(const char *conname, Oid namespaceid)
+{
+ bool found;
+ Relation conDesc;
+ SysScanDesc conscan;
+ ScanKeyData skey[2];
+
+ conDesc = heap_open(ConstraintRelationId, AccessShareLock);
ScanKeyInit(&skey[0],
Anum_pg_constraint_conname,
@@ -652,26 +693,12 @@ ConstraintNameIsUsed(ConstraintCategory conCat, Oid objId,
ScanKeyInit(&skey[1],
Anum_pg_constraint_connamespace,
BTEqualStrategyNumber, F_OIDEQ,
- ObjectIdGetDatum(objNamespace));
+ ObjectIdGetDatum(namespaceid));
conscan = systable_beginscan(conDesc, ConstraintNameNspIndexId, true,
NULL, 2, skey);
- while (HeapTupleIsValid(tup = systable_getnext(conscan)))
- {
- Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tup);
-
- if (conCat == CONSTRAINT_RELATION && con->conrelid == objId)
- {
- found = true;
- break;
- }
- else if (conCat == CONSTRAINT_DOMAIN && con->contypid == objId)
- {
- found = true;
- break;
- }
- }
+ found = (HeapTupleIsValid(systable_getnext(conscan)));
systable_endscan(conscan);
heap_close(conDesc, AccessShareLock);
@@ -878,13 +905,11 @@ RenameConstraintById(Oid conId, const char *newname)
con = (Form_pg_constraint) GETSTRUCT(tuple);
/*
- * We need to check whether the name is already in use --- note that there
- * currently is not a unique index that would catch this.
+ * For user-friendliness, check whether the name is already in use.
*/
if (OidIsValid(con->conrelid) &&
ConstraintNameIsUsed(CONSTRAINT_RELATION,
con->conrelid,
- con->connamespace,
newname))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
@@ -893,7 +918,6 @@ RenameConstraintById(Oid conId, const char *newname)
if (OidIsValid(con->contypid) &&
ConstraintNameIsUsed(CONSTRAINT_DOMAIN,
con->contypid,
- con->connamespace,
newname))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
@@ -923,32 +947,23 @@ AlterConstraintNamespaces(Oid ownerId, Oid oldNspId,
Oid newNspId, bool isType, ObjectAddresses *objsMoved)
{
Relation conRel;
- ScanKeyData key[1];
+ ScanKeyData key[2];
SysScanDesc scan;
HeapTuple tup;
conRel = heap_open(ConstraintRelationId, RowExclusiveLock);
- if (isType)
- {
- ScanKeyInit(&key[0],
- Anum_pg_constraint_contypid,
- BTEqualStrategyNumber, F_OIDEQ,
- ObjectIdGetDatum(ownerId));
-
- scan = systable_beginscan(conRel, ConstraintTypidIndexId, true,
- NULL, 1, key);
- }
- else
- {
- ScanKeyInit(&key[0],
- Anum_pg_constraint_conrelid,
- BTEqualStrategyNumber, F_OIDEQ,
- ObjectIdGetDatum(ownerId));
+ ScanKeyInit(&key[0],
+ Anum_pg_constraint_conrelid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(isType ? InvalidOid : ownerId));
+ ScanKeyInit(&key[1],
+ Anum_pg_constraint_contypid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(isType ? ownerId : InvalidOid));
- scan = systable_beginscan(conRel, ConstraintRelidIndexId, true,
- NULL, 1, key);
- }
+ scan = systable_beginscan(conRel, ConstraintRelidTypidNameIndexId, true,
+ NULL, 2, key);
while (HeapTupleIsValid((tup = systable_getnext(scan))))
{
@@ -1038,38 +1053,30 @@ get_relation_constraint_oid(Oid relid, const char *conname, bool missing_ok)
Relation pg_constraint;
HeapTuple tuple;
SysScanDesc scan;
- ScanKeyData skey[1];
+ ScanKeyData skey[3];
Oid conOid = InvalidOid;
- /*
- * Fetch the constraint tuple from pg_constraint. There may be more than
- * one match, because constraints are not required to have unique names;
- * if so, error out.
- */
pg_constraint = heap_open(ConstraintRelationId, AccessShareLock);
ScanKeyInit(&skey[0],
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
+ ScanKeyInit(&skey[1],
+ Anum_pg_constraint_contypid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(InvalidOid));
+ ScanKeyInit(&skey[2],
+ Anum_pg_constraint_conname,
+ BTEqualStrategyNumber, F_NAMEEQ,
+ CStringGetDatum(conname));
- scan = systable_beginscan(pg_constraint, ConstraintRelidIndexId, true,
- NULL, 1, skey);
-
- while (HeapTupleIsValid(tuple = systable_getnext(scan)))
- {
- Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
+ scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
+ NULL, 3, skey);
- if (strcmp(NameStr(con->conname), conname) == 0)
- {
- if (OidIsValid(conOid))
- ereport(ERROR,
- (errcode(ERRCODE_DUPLICATE_OBJECT),
- errmsg("table \"%s\" has multiple constraints named \"%s\"",
- get_rel_name(relid), conname)));
- conOid = HeapTupleGetOid(tuple);
- }
- }
+ /* There can be at most one matching row */
+ if (HeapTupleIsValid(tuple = systable_getnext(scan)))
+ conOid = HeapTupleGetOid(tuple);
systable_endscan(scan);
@@ -1105,67 +1112,62 @@ get_relation_constraint_attnos(Oid relid, const char *conname,
Relation pg_constraint;
HeapTuple tuple;
SysScanDesc scan;
- ScanKeyData skey[1];
+ ScanKeyData skey[3];
/* Set *constraintOid, to avoid complaints about uninitialized vars */
*constraintOid = InvalidOid;
- /*
- * Fetch the constraint tuple from pg_constraint. There may be more than
- * one match, because constraints are not required to have unique names;
- * if so, error out.
- */
pg_constraint = heap_open(ConstraintRelationId, AccessShareLock);
ScanKeyInit(&skey[0],
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
+ ScanKeyInit(&skey[1],
+ Anum_pg_constraint_contypid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(InvalidOid));
+ ScanKeyInit(&skey[2],
+ Anum_pg_constraint_conname,
+ BTEqualStrategyNumber, F_NAMEEQ,
+ CStringGetDatum(conname));
- scan = systable_beginscan(pg_constraint, ConstraintRelidIndexId, true,
- NULL, 1, skey);
+ scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
+ NULL, 3, skey);
- while (HeapTupleIsValid(tuple = systable_getnext(scan)))
+ /* There can be at most one matching row */
+ if (HeapTupleIsValid(tuple = systable_getnext(scan)))
{
- Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
Datum adatum;
bool isNull;
- ArrayType *arr;
- int16 *attnums;
- int numcols;
- int i;
-
- /* Check the constraint name */
- if (strcmp(NameStr(con->conname), conname) != 0)
- continue;
- if (OidIsValid(*constraintOid))
- ereport(ERROR,
- (errcode(ERRCODE_DUPLICATE_OBJECT),
- errmsg("table \"%s\" has multiple constraints named \"%s\"",
- get_rel_name(relid), conname)));
*constraintOid = HeapTupleGetOid(tuple);
/* Extract the conkey array, ie, attnums of constrained columns */
adatum = heap_getattr(tuple, Anum_pg_constraint_conkey,
RelationGetDescr(pg_constraint), &isNull);
- if (isNull)
- continue; /* no constrained columns */
-
- arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
- numcols = ARR_DIMS(arr)[0];
- if (ARR_NDIM(arr) != 1 ||
- numcols < 0 ||
- ARR_HASNULL(arr) ||
- ARR_ELEMTYPE(arr) != INT2OID)
- elog(ERROR, "conkey is not a 1-D smallint array");
- attnums = (int16 *) ARR_DATA_PTR(arr);
-
- /* Construct the result value */
- for (i = 0; i < numcols; i++)
+ if (!isNull)
{
- conattnos = bms_add_member(conattnos,
- attnums[i] - FirstLowInvalidHeapAttributeNumber);
+ ArrayType *arr;
+ int numcols;
+ int16 *attnums;
+ int i;
+
+ arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
+ numcols = ARR_DIMS(arr)[0];
+ if (ARR_NDIM(arr) != 1 ||
+ numcols < 0 ||
+ ARR_HASNULL(arr) ||
+ ARR_ELEMTYPE(arr) != INT2OID)
+ elog(ERROR, "conkey is not a 1-D smallint array");
+ attnums = (int16 *) ARR_DATA_PTR(arr);
+
+ /* Construct the result value */
+ for (i = 0; i < numcols; i++)
+ {
+ conattnos = bms_add_member(conattnos,
+ attnums[i] - FirstLowInvalidHeapAttributeNumber);
+ }
}
}
@@ -1203,7 +1205,7 @@ get_relation_idx_constraint_oid(Oid relationId, Oid indexId)
BTEqualStrategyNumber,
F_OIDEQ,
ObjectIdGetDatum(relationId));
- scan = systable_beginscan(pg_constraint, ConstraintRelidIndexId,
+ scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId,
true, NULL, 1, &key);
while ((tuple = systable_getnext(scan)) != NULL)
{
@@ -1233,38 +1235,30 @@ get_domain_constraint_oid(Oid typid, const char *conname, bool missing_ok)
Relation pg_constraint;
HeapTuple tuple;
SysScanDesc scan;
- ScanKeyData skey[1];
+ ScanKeyData skey[3];
Oid conOid = InvalidOid;
- /*
- * Fetch the constraint tuple from pg_constraint. There may be more than
- * one match, because constraints are not required to have unique names;
- * if so, error out.
- */
pg_constraint = heap_open(ConstraintRelationId, AccessShareLock);
ScanKeyInit(&skey[0],
+ Anum_pg_constraint_conrelid,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(InvalidOid));
+ ScanKeyInit(&skey[1],
Anum_pg_constraint_contypid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(typid));
+ ScanKeyInit(&skey[2],
+ Anum_pg_constraint_conname,
+ BTEqualStrategyNumber, F_NAMEEQ,
+ CStringGetDatum(conname));
- scan = systable_beginscan(pg_constraint, ConstraintTypidIndexId, true,
- NULL, 1, skey);
-
- while (HeapTupleIsValid(tuple = systable_getnext(scan)))
- {
- Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
+ scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
+ NULL, 3, skey);
- if (strcmp(NameStr(con->conname), conname) == 0)
- {
- if (OidIsValid(conOid))
- ereport(ERROR,
- (errcode(ERRCODE_DUPLICATE_OBJECT),
- errmsg("domain %s has multiple constraints named \"%s\"",
- format_type_be(typid), conname)));
- conOid = HeapTupleGetOid(tuple);
- }
- }
+ /* There can be at most one matching row */
+ if (HeapTupleIsValid(tuple = systable_getnext(scan)))
+ conOid = HeapTupleGetOid(tuple);
systable_endscan(scan);
@@ -1314,7 +1308,7 @@ get_primary_key_attnos(Oid relid, bool deferrableOk, Oid *constraintOid)
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
- scan = systable_beginscan(pg_constraint, ConstraintRelidIndexId, true,
+ scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
NULL, 1, skey);
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-02 23:41:50 +0000