Move pg_attrdef manipulation code into new file catalog/pg_attrdef.c.
This is a pure refactoring commit: there isn't (I hope) any functional change. StoreAttrDefault and RemoveAttrDefault[ById] are moved from heap.c, reducing the size of that overly-large file by about 300 lines. I took the opportunity to trim unused #includes from heap.c, too. Two new functions for translating between a pg_attrdef OID and the relid/attnum of the owning column are created by extracting ad-hoc code from objectaddress.c. This already removes one copy of said code, and a follow-on bug fix will create more callers. The only other function directly manipulating pg_attrdef is AttrDefaultFetch. I judged it was better to leave that in relcache.c, since it shares special concerns about recursion and error handling with the rest of that module. Discussion: https://postgr.es/m/651168.1647451676@sss.pgh.pa.us
This commit is contained in:
Tom Lane
parent
7b6ec86532
commit
17f3bc0928
src
backend
include/catalog
@ -25,6 +25,7 @@ OBJS = \
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objectaddress.o \
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partition.o \
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pg_aggregate.o \
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pg_attrdef.o \
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pg_cast.o \
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pg_class.o \
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pg_collation.o \
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@ -30,19 +30,11 @@
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#include "postgres.h"
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#include "access/genam.h"
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#include "access/htup_details.h"
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#include "access/multixact.h"
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#include "access/relation.h"
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#include "access/sysattr.h"
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#include "access/table.h"
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#include "access/tableam.h"
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#include "access/toast_compression.h"
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#include "access/transam.h"
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#include "access/xact.h"
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#include "access/xlog.h"
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#include "catalog/binary_upgrade.h"
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#include "catalog/catalog.h"
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#include "catalog/dependency.h"
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#include "catalog/heap.h"
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#include "catalog/index.h"
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#include "catalog/objectaccess.h"
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@ -61,10 +53,8 @@
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#include "catalog/pg_tablespace.h"
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#include "catalog/pg_type.h"
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#include "catalog/storage.h"
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#include "catalog/storage_xlog.h"
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#include "commands/tablecmds.h"
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#include "commands/typecmds.h"
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#include "executor/executor.h"
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#include "miscadmin.h"
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#include "nodes/nodeFuncs.h"
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#include "optimizer/optimizer.h"
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@ -76,16 +66,10 @@
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#include "partitioning/partdesc.h"
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#include "storage/lmgr.h"
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#include "storage/predicate.h"
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#include "storage/smgr.h"
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#include "utils/acl.h"
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#include "utils/builtins.h"
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#include "utils/datum.h"
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#include "utils/fmgroids.h"
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#include "utils/inval.h"
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#include "utils/lsyscache.h"
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#include "utils/partcache.h"
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#include "utils/ruleutils.h"
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#include "utils/snapmgr.h"
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#include "utils/syscache.h"
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@ -1757,131 +1741,6 @@ RemoveAttributeById(Oid relid, AttrNumber attnum)
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relation_close(rel, NoLock);
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}
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/*
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* RemoveAttrDefault
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*
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* If the specified relation/attribute has a default, remove it.
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* (If no default, raise error if complain is true, else return quietly.)
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*/
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void
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RemoveAttrDefault(Oid relid, AttrNumber attnum,
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DropBehavior behavior, bool complain, bool internal)
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{
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Relation attrdef_rel;
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ScanKeyData scankeys[2];
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SysScanDesc scan;
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HeapTuple tuple;
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bool found = false;
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attrdef_rel = table_open(AttrDefaultRelationId, RowExclusiveLock);
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ScanKeyInit(&scankeys[0],
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Anum_pg_attrdef_adrelid,
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BTEqualStrategyNumber, F_OIDEQ,
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ObjectIdGetDatum(relid));
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ScanKeyInit(&scankeys[1],
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Anum_pg_attrdef_adnum,
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BTEqualStrategyNumber, F_INT2EQ,
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Int16GetDatum(attnum));
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scan = systable_beginscan(attrdef_rel, AttrDefaultIndexId, true,
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NULL, 2, scankeys);
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/* There should be at most one matching tuple, but we loop anyway */
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while (HeapTupleIsValid(tuple = systable_getnext(scan)))
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{
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ObjectAddress object;
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Form_pg_attrdef attrtuple = (Form_pg_attrdef) GETSTRUCT(tuple);
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object.classId = AttrDefaultRelationId;
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object.objectId = attrtuple->oid;
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object.objectSubId = 0;
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performDeletion(&object, behavior,
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internal ? PERFORM_DELETION_INTERNAL : 0);
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found = true;
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}
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systable_endscan(scan);
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table_close(attrdef_rel, RowExclusiveLock);
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if (complain && !found)
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elog(ERROR, "could not find attrdef tuple for relation %u attnum %d",
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relid, attnum);
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}
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/*
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* RemoveAttrDefaultById
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*
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* Remove a pg_attrdef entry specified by OID. This is the guts of
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* attribute-default removal. Note it should be called via performDeletion,
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* not directly.
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*/
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void
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RemoveAttrDefaultById(Oid attrdefId)
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{
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Relation attrdef_rel;
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Relation attr_rel;
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Relation myrel;
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ScanKeyData scankeys[1];
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SysScanDesc scan;
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HeapTuple tuple;
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Oid myrelid;
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AttrNumber myattnum;
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/* Grab an appropriate lock on the pg_attrdef relation */
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attrdef_rel = table_open(AttrDefaultRelationId, RowExclusiveLock);
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/* Find the pg_attrdef tuple */
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ScanKeyInit(&scankeys[0],
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Anum_pg_attrdef_oid,
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BTEqualStrategyNumber, F_OIDEQ,
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ObjectIdGetDatum(attrdefId));
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scan = systable_beginscan(attrdef_rel, AttrDefaultOidIndexId, true,
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NULL, 1, scankeys);
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tuple = systable_getnext(scan);
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if (!HeapTupleIsValid(tuple))
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elog(ERROR, "could not find tuple for attrdef %u", attrdefId);
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myrelid = ((Form_pg_attrdef) GETSTRUCT(tuple))->adrelid;
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myattnum = ((Form_pg_attrdef) GETSTRUCT(tuple))->adnum;
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/* Get an exclusive lock on the relation owning the attribute */
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myrel = relation_open(myrelid, AccessExclusiveLock);
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/* Now we can delete the pg_attrdef row */
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CatalogTupleDelete(attrdef_rel, &tuple->t_self);
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systable_endscan(scan);
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table_close(attrdef_rel, RowExclusiveLock);
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/* Fix the pg_attribute row */
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attr_rel = table_open(AttributeRelationId, RowExclusiveLock);
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tuple = SearchSysCacheCopy2(ATTNUM,
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ObjectIdGetDatum(myrelid),
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Int16GetDatum(myattnum));
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if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
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elog(ERROR, "cache lookup failed for attribute %d of relation %u",
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myattnum, myrelid);
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((Form_pg_attribute) GETSTRUCT(tuple))->atthasdef = false;
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CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);
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/*
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* Our update of the pg_attribute row will force a relcache rebuild, so
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* there's nothing else to do here.
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*/
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table_close(attr_rel, RowExclusiveLock);
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/* Keep lock on attribute's rel until end of xact */
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relation_close(myrel, NoLock);
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}
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/*
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* heap_drop_with_catalog - removes specified relation from catalogs
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*
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@ -2193,195 +2052,6 @@ SetAttrMissing(Oid relid, char *attname, char *value)
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table_close(tablerel, AccessExclusiveLock);
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}
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/*
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* Store a default expression for column attnum of relation rel.
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*
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* Returns the OID of the new pg_attrdef tuple.
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*
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* add_column_mode must be true if we are storing the default for a new
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* attribute, and false if it's for an already existing attribute. The reason
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* for this is that the missing value must never be updated after it is set,
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* which can only be when a column is added to the table. Otherwise we would
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* in effect be changing existing tuples.
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*/
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Oid
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StoreAttrDefault(Relation rel, AttrNumber attnum,
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Node *expr, bool is_internal, bool add_column_mode)
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{
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char *adbin;
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Relation adrel;
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HeapTuple tuple;
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Datum values[4];
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static bool nulls[4] = {false, false, false, false};
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Relation attrrel;
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HeapTuple atttup;
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Form_pg_attribute attStruct;
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char attgenerated;
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Oid attrdefOid;
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ObjectAddress colobject,
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defobject;
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adrel = table_open(AttrDefaultRelationId, RowExclusiveLock);
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/*
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* Flatten expression to string form for storage.
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*/
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adbin = nodeToString(expr);
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/*
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* Make the pg_attrdef entry.
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*/
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attrdefOid = GetNewOidWithIndex(adrel, AttrDefaultOidIndexId,
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Anum_pg_attrdef_oid);
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values[Anum_pg_attrdef_oid - 1] = ObjectIdGetDatum(attrdefOid);
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values[Anum_pg_attrdef_adrelid - 1] = RelationGetRelid(rel);
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values[Anum_pg_attrdef_adnum - 1] = attnum;
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values[Anum_pg_attrdef_adbin - 1] = CStringGetTextDatum(adbin);
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tuple = heap_form_tuple(adrel->rd_att, values, nulls);
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CatalogTupleInsert(adrel, tuple);
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defobject.classId = AttrDefaultRelationId;
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defobject.objectId = attrdefOid;
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defobject.objectSubId = 0;
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table_close(adrel, RowExclusiveLock);
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/* now can free some of the stuff allocated above */
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pfree(DatumGetPointer(values[Anum_pg_attrdef_adbin - 1]));
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heap_freetuple(tuple);
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pfree(adbin);
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/*
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* Update the pg_attribute entry for the column to show that a default
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* exists.
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*/
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attrrel = table_open(AttributeRelationId, RowExclusiveLock);
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atttup = SearchSysCacheCopy2(ATTNUM,
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ObjectIdGetDatum(RelationGetRelid(rel)),
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Int16GetDatum(attnum));
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if (!HeapTupleIsValid(atttup))
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elog(ERROR, "cache lookup failed for attribute %d of relation %u",
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attnum, RelationGetRelid(rel));
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attStruct = (Form_pg_attribute) GETSTRUCT(atttup);
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attgenerated = attStruct->attgenerated;
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if (!attStruct->atthasdef)
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{
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Form_pg_attribute defAttStruct;
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ExprState *exprState;
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Expr *expr2 = (Expr *) expr;
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EState *estate = NULL;
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ExprContext *econtext;
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Datum valuesAtt[Natts_pg_attribute];
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bool nullsAtt[Natts_pg_attribute];
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bool replacesAtt[Natts_pg_attribute];
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Datum missingval = (Datum) 0;
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bool missingIsNull = true;
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MemSet(valuesAtt, 0, sizeof(valuesAtt));
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MemSet(nullsAtt, false, sizeof(nullsAtt));
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MemSet(replacesAtt, false, sizeof(replacesAtt));
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valuesAtt[Anum_pg_attribute_atthasdef - 1] = true;
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replacesAtt[Anum_pg_attribute_atthasdef - 1] = true;
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if (rel->rd_rel->relkind == RELKIND_RELATION && add_column_mode &&
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!attgenerated)
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{
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expr2 = expression_planner(expr2);
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estate = CreateExecutorState();
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exprState = ExecPrepareExpr(expr2, estate);
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econtext = GetPerTupleExprContext(estate);
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missingval = ExecEvalExpr(exprState, econtext,
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&missingIsNull);
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FreeExecutorState(estate);
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defAttStruct = TupleDescAttr(rel->rd_att, attnum - 1);
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if (missingIsNull)
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{
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/* if the default evaluates to NULL, just store a NULL array */
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missingval = (Datum) 0;
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}
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else
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{
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/* otherwise make a one-element array of the value */
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missingval = PointerGetDatum(construct_array(&missingval,
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1,
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defAttStruct->atttypid,
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defAttStruct->attlen,
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defAttStruct->attbyval,
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defAttStruct->attalign));
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}
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valuesAtt[Anum_pg_attribute_atthasmissing - 1] = !missingIsNull;
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replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
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valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
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replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;
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nullsAtt[Anum_pg_attribute_attmissingval - 1] = missingIsNull;
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}
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atttup = heap_modify_tuple(atttup, RelationGetDescr(attrrel),
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valuesAtt, nullsAtt, replacesAtt);
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CatalogTupleUpdate(attrrel, &atttup->t_self, atttup);
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if (!missingIsNull)
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pfree(DatumGetPointer(missingval));
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}
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table_close(attrrel, RowExclusiveLock);
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heap_freetuple(atttup);
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/*
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* Make a dependency so that the pg_attrdef entry goes away if the column
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* (or whole table) is deleted.
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*/
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colobject.classId = RelationRelationId;
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colobject.objectId = RelationGetRelid(rel);
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colobject.objectSubId = attnum;
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recordDependencyOn(&defobject, &colobject, DEPENDENCY_AUTO);
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/*
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* Record dependencies on objects used in the expression, too.
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*/
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if (attgenerated)
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{
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/*
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* Generated column: Dropping anything that the generation expression
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* refers to automatically drops the generated column.
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*/
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recordDependencyOnSingleRelExpr(&colobject, expr, RelationGetRelid(rel),
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DEPENDENCY_AUTO,
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DEPENDENCY_AUTO, false);
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}
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else
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{
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/*
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* Normal default: Dropping anything that the default refers to
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* requires CASCADE and drops the default only.
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*/
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recordDependencyOnSingleRelExpr(&defobject, expr, RelationGetRelid(rel),
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DEPENDENCY_NORMAL,
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DEPENDENCY_NORMAL, false);
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}
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/*
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* Post creation hook for attribute defaults.
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*
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* XXX. ALTER TABLE ALTER COLUMN SET/DROP DEFAULT is implemented with a
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* couple of deletion/creation of the attribute's default entry, so the
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* callee should check existence of an older version of this entry if it
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* needs to distinguish.
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*/
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InvokeObjectPostCreateHookArg(AttrDefaultRelationId,
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RelationGetRelid(rel), attnum, is_internal);
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return attrdefOid;
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}
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/*
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* Store a check-constraint expression for the given relation.
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*
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@ -1578,39 +1578,11 @@ get_object_address_attrdef(ObjectType objtype, List *object,
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tupdesc = RelationGetDescr(relation);
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/* Look up attribute number and scan pg_attrdef to find its tuple */
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/* Look up attribute number and fetch the pg_attrdef OID */
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attnum = get_attnum(reloid, attname);
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defoid = InvalidOid;
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if (attnum != InvalidAttrNumber && tupdesc->constr != NULL)
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{
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Relation attrdef;
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ScanKeyData keys[2];
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SysScanDesc scan;
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HeapTuple tup;
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attrdef = relation_open(AttrDefaultRelationId, AccessShareLock);
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ScanKeyInit(&keys[0],
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Anum_pg_attrdef_adrelid,
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BTEqualStrategyNumber,
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F_OIDEQ,
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ObjectIdGetDatum(reloid));
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ScanKeyInit(&keys[1],
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Anum_pg_attrdef_adnum,
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BTEqualStrategyNumber,
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F_INT2EQ,
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Int16GetDatum(attnum));
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scan = systable_beginscan(attrdef, AttrDefaultIndexId, true,
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NULL, 2, keys);
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if (HeapTupleIsValid(tup = systable_getnext(scan)))
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{
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Form_pg_attrdef atdform = (Form_pg_attrdef) GETSTRUCT(tup);
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defoid = atdform->oid;
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}
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systable_endscan(scan);
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relation_close(attrdef, AccessShareLock);
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}
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defoid = GetAttrDefaultOid(reloid, attnum);
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if (!OidIsValid(defoid))
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{
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if (!missing_ok)
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@ -3161,48 +3133,21 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok)
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case OCLASS_DEFAULT:
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{
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Relation attrdefDesc;
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ScanKeyData skey[1];
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SysScanDesc adscan;
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HeapTuple tup;
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Form_pg_attrdef attrdef;
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ObjectAddress colobject;
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attrdefDesc = table_open(AttrDefaultRelationId, AccessShareLock);
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colobject = GetAttrDefaultColumnAddress(object->objectId);
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ScanKeyInit(&skey[0],
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Anum_pg_attrdef_oid,
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BTEqualStrategyNumber, F_OIDEQ,
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ObjectIdGetDatum(object->objectId));
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adscan = systable_beginscan(attrdefDesc, AttrDefaultOidIndexId,
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true, NULL, 1, skey);
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tup = systable_getnext(adscan);
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if (!HeapTupleIsValid(tup))
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if (!OidIsValid(colobject.objectId))
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{
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if (!missing_ok)
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elog(ERROR, "could not find tuple for attrdef %u",
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object->objectId);
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systable_endscan(adscan);
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table_close(attrdefDesc, AccessShareLock);
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break;
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}
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attrdef = (Form_pg_attrdef) GETSTRUCT(tup);
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||||
|
||||
colobject.classId = RelationRelationId;
|
||||
colobject.objectId = attrdef->adrelid;
|
||||
colobject.objectSubId = attrdef->adnum;
|
||||
|
||||
/* translator: %s is typically "column %s of table %s" */
|
||||
appendStringInfo(&buffer, _("default value for %s"),
|
||||
getObjectDescription(&colobject, false));
|
||||
|
||||
systable_endscan(adscan);
|
||||
table_close(attrdefDesc, AccessShareLock);
|
||||
break;
|
||||
}
|
||||
|
||||
@ -5006,50 +4951,22 @@ getObjectIdentityParts(const ObjectAddress *object,
|
||||
|
||||
case OCLASS_DEFAULT:
|
||||
{
|
||||
Relation attrdefDesc;
|
||||
ScanKeyData skey[1];
|
||||
SysScanDesc adscan;
|
||||
|
||||
HeapTuple tup;
|
||||
Form_pg_attrdef attrdef;
|
||||
ObjectAddress colobject;
|
||||
|
||||
attrdefDesc = table_open(AttrDefaultRelationId, AccessShareLock);
|
||||
colobject = GetAttrDefaultColumnAddress(object->objectId);
|
||||
|
||||
ScanKeyInit(&skey[0],
|
||||
Anum_pg_attrdef_oid,
|
||||
BTEqualStrategyNumber, F_OIDEQ,
|
||||
ObjectIdGetDatum(object->objectId));
|
||||
|
||||
adscan = systable_beginscan(attrdefDesc, AttrDefaultOidIndexId,
|
||||
true, NULL, 1, skey);
|
||||
|
||||
tup = systable_getnext(adscan);
|
||||
|
||||
if (!HeapTupleIsValid(tup))
|
||||
if (!OidIsValid(colobject.objectId))
|
||||
{
|
||||
if (!missing_ok)
|
||||
elog(ERROR, "could not find tuple for attrdef %u",
|
||||
object->objectId);
|
||||
|
||||
systable_endscan(adscan);
|
||||
table_close(attrdefDesc, AccessShareLock);
|
||||
break;
|
||||
}
|
||||
|
||||
attrdef = (Form_pg_attrdef) GETSTRUCT(tup);
|
||||
|
||||
colobject.classId = RelationRelationId;
|
||||
colobject.objectId = attrdef->adrelid;
|
||||
colobject.objectSubId = attrdef->adnum;
|
||||
|
||||
appendStringInfo(&buffer, "for %s",
|
||||
getObjectIdentityParts(&colobject,
|
||||
objname, objargs,
|
||||
false));
|
||||
|
||||
systable_endscan(adscan);
|
||||
table_close(attrdefDesc, AccessShareLock);
|
||||
break;
|
||||
}
|
||||
|
||||
|
||||
428
src/backend/catalog/pg_attrdef.c
Normal file
428
src/backend/catalog/pg_attrdef.c
Normal file
@ -0,0 +1,428 @@
|
||||
/*-------------------------------------------------------------------------
|
||||
*
|
||||
* pg_attrdef.c
|
||||
* routines to support manipulation of the pg_attrdef relation
|
||||
*
|
||||
* Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* src/backend/catalog/pg_attrdef.c
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
#include "postgres.h"
|
||||
|
||||
#include "access/genam.h"
|
||||
#include "access/relation.h"
|
||||
#include "access/table.h"
|
||||
#include "catalog/catalog.h"
|
||||
#include "catalog/dependency.h"
|
||||
#include "catalog/indexing.h"
|
||||
#include "catalog/objectaccess.h"
|
||||
#include "catalog/pg_attrdef.h"
|
||||
#include "executor/executor.h"
|
||||
#include "optimizer/optimizer.h"
|
||||
#include "utils/array.h"
|
||||
#include "utils/builtins.h"
|
||||
#include "utils/fmgroids.h"
|
||||
#include "utils/rel.h"
|
||||
#include "utils/syscache.h"
|
||||
|
||||
|
||||
/*
|
||||
* Store a default expression for column attnum of relation rel.
|
||||
*
|
||||
* Returns the OID of the new pg_attrdef tuple.
|
||||
*
|
||||
* add_column_mode must be true if we are storing the default for a new
|
||||
* attribute, and false if it's for an already existing attribute. The reason
|
||||
* for this is that the missing value must never be updated after it is set,
|
||||
* which can only be when a column is added to the table. Otherwise we would
|
||||
* in effect be changing existing tuples.
|
||||
*/
|
||||
Oid
|
||||
StoreAttrDefault(Relation rel, AttrNumber attnum,
|
||||
Node *expr, bool is_internal, bool add_column_mode)
|
||||
{
|
||||
char *adbin;
|
||||
Relation adrel;
|
||||
HeapTuple tuple;
|
||||
Datum values[4];
|
||||
static bool nulls[4] = {false, false, false, false};
|
||||
Relation attrrel;
|
||||
HeapTuple atttup;
|
||||
Form_pg_attribute attStruct;
|
||||
char attgenerated;
|
||||
Oid attrdefOid;
|
||||
ObjectAddress colobject,
|
||||
defobject;
|
||||
|
||||
adrel = table_open(AttrDefaultRelationId, RowExclusiveLock);
|
||||
|
||||
/*
|
||||
* Flatten expression to string form for storage.
|
||||
*/
|
||||
adbin = nodeToString(expr);
|
||||
|
||||
/*
|
||||
* Make the pg_attrdef entry.
|
||||
*/
|
||||
attrdefOid = GetNewOidWithIndex(adrel, AttrDefaultOidIndexId,
|
||||
Anum_pg_attrdef_oid);
|
||||
values[Anum_pg_attrdef_oid - 1] = ObjectIdGetDatum(attrdefOid);
|
||||
values[Anum_pg_attrdef_adrelid - 1] = RelationGetRelid(rel);
|
||||
values[Anum_pg_attrdef_adnum - 1] = attnum;
|
||||
values[Anum_pg_attrdef_adbin - 1] = CStringGetTextDatum(adbin);
|
||||
|
||||
tuple = heap_form_tuple(adrel->rd_att, values, nulls);
|
||||
CatalogTupleInsert(adrel, tuple);
|
||||
|
||||
defobject.classId = AttrDefaultRelationId;
|
||||
defobject.objectId = attrdefOid;
|
||||
defobject.objectSubId = 0;
|
||||
|
||||
table_close(adrel, RowExclusiveLock);
|
||||
|
||||
/* now can free some of the stuff allocated above */
|
||||
pfree(DatumGetPointer(values[Anum_pg_attrdef_adbin - 1]));
|
||||
heap_freetuple(tuple);
|
||||
pfree(adbin);
|
||||
|
||||
/*
|
||||
* Update the pg_attribute entry for the column to show that a default
|
||||
* exists.
|
||||
*/
|
||||
attrrel = table_open(AttributeRelationId, RowExclusiveLock);
|
||||
atttup = SearchSysCacheCopy2(ATTNUM,
|
||||
ObjectIdGetDatum(RelationGetRelid(rel)),
|
||||
Int16GetDatum(attnum));
|
||||
if (!HeapTupleIsValid(atttup))
|
||||
elog(ERROR, "cache lookup failed for attribute %d of relation %u",
|
||||
attnum, RelationGetRelid(rel));
|
||||
attStruct = (Form_pg_attribute) GETSTRUCT(atttup);
|
||||
attgenerated = attStruct->attgenerated;
|
||||
if (!attStruct->atthasdef)
|
||||
{
|
||||
Form_pg_attribute defAttStruct;
|
||||
|
||||
ExprState *exprState;
|
||||
Expr *expr2 = (Expr *) expr;
|
||||
EState *estate = NULL;
|
||||
ExprContext *econtext;
|
||||
Datum valuesAtt[Natts_pg_attribute];
|
||||
bool nullsAtt[Natts_pg_attribute];
|
||||
bool replacesAtt[Natts_pg_attribute];
|
||||
Datum missingval = (Datum) 0;
|
||||
bool missingIsNull = true;
|
||||
|
||||
MemSet(valuesAtt, 0, sizeof(valuesAtt));
|
||||
MemSet(nullsAtt, false, sizeof(nullsAtt));
|
||||
MemSet(replacesAtt, false, sizeof(replacesAtt));
|
||||
valuesAtt[Anum_pg_attribute_atthasdef - 1] = true;
|
||||
replacesAtt[Anum_pg_attribute_atthasdef - 1] = true;
|
||||
|
||||
if (rel->rd_rel->relkind == RELKIND_RELATION && add_column_mode &&
|
||||
!attgenerated)
|
||||
{
|
||||
expr2 = expression_planner(expr2);
|
||||
estate = CreateExecutorState();
|
||||
exprState = ExecPrepareExpr(expr2, estate);
|
||||
econtext = GetPerTupleExprContext(estate);
|
||||
|
||||
missingval = ExecEvalExpr(exprState, econtext,
|
||||
&missingIsNull);
|
||||
|
||||
FreeExecutorState(estate);
|
||||
|
||||
defAttStruct = TupleDescAttr(rel->rd_att, attnum - 1);
|
||||
|
||||
if (missingIsNull)
|
||||
{
|
||||
/* if the default evaluates to NULL, just store a NULL array */
|
||||
missingval = (Datum) 0;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* otherwise make a one-element array of the value */
|
||||
missingval = PointerGetDatum(construct_array(&missingval,
|
||||
1,
|
||||
defAttStruct->atttypid,
|
||||
defAttStruct->attlen,
|
||||
defAttStruct->attbyval,
|
||||
defAttStruct->attalign));
|
||||
}
|
||||
|
||||
valuesAtt[Anum_pg_attribute_atthasmissing - 1] = !missingIsNull;
|
||||
replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
|
||||
valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
|
||||
replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;
|
||||
nullsAtt[Anum_pg_attribute_attmissingval - 1] = missingIsNull;
|
||||
}
|
||||
atttup = heap_modify_tuple(atttup, RelationGetDescr(attrrel),
|
||||
valuesAtt, nullsAtt, replacesAtt);
|
||||
|
||||
CatalogTupleUpdate(attrrel, &atttup->t_self, atttup);
|
||||
|
||||
if (!missingIsNull)
|
||||
pfree(DatumGetPointer(missingval));
|
||||
|
||||
}
|
||||
table_close(attrrel, RowExclusiveLock);
|
||||
heap_freetuple(atttup);
|
||||
|
||||
/*
|
||||
* Make a dependency so that the pg_attrdef entry goes away if the column
|
||||
* (or whole table) is deleted.
|
||||
*/
|
||||
colobject.classId = RelationRelationId;
|
||||
colobject.objectId = RelationGetRelid(rel);
|
||||
colobject.objectSubId = attnum;
|
||||
|
||||
recordDependencyOn(&defobject, &colobject, DEPENDENCY_AUTO);
|
||||
|
||||
/*
|
||||
* Record dependencies on objects used in the expression, too.
|
||||
*/
|
||||
if (attgenerated)
|
||||
{
|
||||
/*
|
||||
* Generated column: Dropping anything that the generation expression
|
||||
* refers to automatically drops the generated column.
|
||||
*/
|
||||
recordDependencyOnSingleRelExpr(&colobject, expr, RelationGetRelid(rel),
|
||||
DEPENDENCY_AUTO,
|
||||
DEPENDENCY_AUTO, false);
|
||||
}
|
||||
else
|
||||
{
|
||||
/*
|
||||
* Normal default: Dropping anything that the default refers to
|
||||
* requires CASCADE and drops the default only.
|
||||
*/
|
||||
recordDependencyOnSingleRelExpr(&defobject, expr, RelationGetRelid(rel),
|
||||
DEPENDENCY_NORMAL,
|
||||
DEPENDENCY_NORMAL, false);
|
||||
}
|
||||
|
||||
/*
|
||||
* Post creation hook for attribute defaults.
|
||||
*
|
||||
* XXX. ALTER TABLE ALTER COLUMN SET/DROP DEFAULT is implemented with a
|
||||
* couple of deletion/creation of the attribute's default entry, so the
|
||||
* callee should check existence of an older version of this entry if it
|
||||
* needs to distinguish.
|
||||
*/
|
||||
InvokeObjectPostCreateHookArg(AttrDefaultRelationId,
|
||||
RelationGetRelid(rel), attnum, is_internal);
|
||||
|
||||
return attrdefOid;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* RemoveAttrDefault
|
||||
*
|
||||
* If the specified relation/attribute has a default, remove it.
|
||||
* (If no default, raise error if complain is true, else return quietly.)
|
||||
*/
|
||||
void
|
||||
RemoveAttrDefault(Oid relid, AttrNumber attnum,
|
||||
DropBehavior behavior, bool complain, bool internal)
|
||||
{
|
||||
Relation attrdef_rel;
|
||||
ScanKeyData scankeys[2];
|
||||
SysScanDesc scan;
|
||||
HeapTuple tuple;
|
||||
bool found = false;
|
||||
|
||||
attrdef_rel = table_open(AttrDefaultRelationId, RowExclusiveLock);
|
||||
|
||||
ScanKeyInit(&scankeys[0],
|
||||
Anum_pg_attrdef_adrelid,
|
||||
BTEqualStrategyNumber, F_OIDEQ,
|
||||
ObjectIdGetDatum(relid));
|
||||
ScanKeyInit(&scankeys[1],
|
||||
Anum_pg_attrdef_adnum,
|
||||
BTEqualStrategyNumber, F_INT2EQ,
|
||||
Int16GetDatum(attnum));
|
||||
|
||||
scan = systable_beginscan(attrdef_rel, AttrDefaultIndexId, true,
|
||||
NULL, 2, scankeys);
|
||||
|
||||
/* There should be at most one matching tuple, but we loop anyway */
|
||||
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
|
||||
{
|
||||
ObjectAddress object;
|
||||
Form_pg_attrdef attrtuple = (Form_pg_attrdef) GETSTRUCT(tuple);
|
||||
|
||||
object.classId = AttrDefaultRelationId;
|
||||
object.objectId = attrtuple->oid;
|
||||
object.objectSubId = 0;
|
||||
|
||||
performDeletion(&object, behavior,
|
||||
internal ? PERFORM_DELETION_INTERNAL : 0);
|
||||
|
||||
found = true;
|
||||
}
|
||||
|
||||
systable_endscan(scan);
|
||||
table_close(attrdef_rel, RowExclusiveLock);
|
||||
|
||||
if (complain && !found)
|
||||
elog(ERROR, "could not find attrdef tuple for relation %u attnum %d",
|
||||
relid, attnum);
|
||||
}
|
||||
|
||||
/*
|
||||
* RemoveAttrDefaultById
|
||||
*
|
||||
* Remove a pg_attrdef entry specified by OID. This is the guts of
|
||||
* attribute-default removal. Note it should be called via performDeletion,
|
||||
* not directly.
|
||||
*/
|
||||
void
|
||||
RemoveAttrDefaultById(Oid attrdefId)
|
||||
{
|
||||
Relation attrdef_rel;
|
||||
Relation attr_rel;
|
||||
Relation myrel;
|
||||
ScanKeyData scankeys[1];
|
||||
SysScanDesc scan;
|
||||
HeapTuple tuple;
|
||||
Oid myrelid;
|
||||
AttrNumber myattnum;
|
||||
|
||||
/* Grab an appropriate lock on the pg_attrdef relation */
|
||||
attrdef_rel = table_open(AttrDefaultRelationId, RowExclusiveLock);
|
||||
|
||||
/* Find the pg_attrdef tuple */
|
||||
ScanKeyInit(&scankeys[0],
|
||||
Anum_pg_attrdef_oid,
|
||||
BTEqualStrategyNumber, F_OIDEQ,
|
||||
ObjectIdGetDatum(attrdefId));
|
||||
|
||||
scan = systable_beginscan(attrdef_rel, AttrDefaultOidIndexId, true,
|
||||
NULL, 1, scankeys);
|
||||
|
||||
tuple = systable_getnext(scan);
|
||||
if (!HeapTupleIsValid(tuple))
|
||||
elog(ERROR, "could not find tuple for attrdef %u", attrdefId);
|
||||
|
||||
myrelid = ((Form_pg_attrdef) GETSTRUCT(tuple))->adrelid;
|
||||
myattnum = ((Form_pg_attrdef) GETSTRUCT(tuple))->adnum;
|
||||
|
||||
/* Get an exclusive lock on the relation owning the attribute */
|
||||
myrel = relation_open(myrelid, AccessExclusiveLock);
|
||||
|
||||
/* Now we can delete the pg_attrdef row */
|
||||
CatalogTupleDelete(attrdef_rel, &tuple->t_self);
|
||||
|
||||
systable_endscan(scan);
|
||||
table_close(attrdef_rel, RowExclusiveLock);
|
||||
|
||||
/* Fix the pg_attribute row */
|
||||
attr_rel = table_open(AttributeRelationId, RowExclusiveLock);
|
||||
|
||||
tuple = SearchSysCacheCopy2(ATTNUM,
|
||||
ObjectIdGetDatum(myrelid),
|
||||
Int16GetDatum(myattnum));
|
||||
if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
|
||||
elog(ERROR, "cache lookup failed for attribute %d of relation %u",
|
||||
myattnum, myrelid);
|
||||
|
||||
((Form_pg_attribute) GETSTRUCT(tuple))->atthasdef = false;
|
||||
|
||||
CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);
|
||||
|
||||
/*
|
||||
* Our update of the pg_attribute row will force a relcache rebuild, so
|
||||
* there's nothing else to do here.
|
||||
*/
|
||||
table_close(attr_rel, RowExclusiveLock);
|
||||
|
||||
/* Keep lock on attribute's rel until end of xact */
|
||||
relation_close(myrel, NoLock);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Get the pg_attrdef OID of the default expression for a column
|
||||
* identified by relation OID and and column number.
|
||||
*
|
||||
* Returns InvalidOid if there is no such pg_attrdef entry.
|
||||
*/
|
||||
Oid
|
||||
GetAttrDefaultOid(Oid relid, AttrNumber attnum)
|
||||
{
|
||||
Oid result = InvalidOid;
|
||||
Relation attrdef;
|
||||
ScanKeyData keys[2];
|
||||
SysScanDesc scan;
|
||||
HeapTuple tup;
|
||||
|
||||
attrdef = table_open(AttrDefaultRelationId, AccessShareLock);
|
||||
ScanKeyInit(&keys[0],
|
||||
Anum_pg_attrdef_adrelid,
|
||||
BTEqualStrategyNumber,
|
||||
F_OIDEQ,
|
||||
ObjectIdGetDatum(relid));
|
||||
ScanKeyInit(&keys[1],
|
||||
Anum_pg_attrdef_adnum,
|
||||
BTEqualStrategyNumber,
|
||||
F_INT2EQ,
|
||||
Int16GetDatum(attnum));
|
||||
scan = systable_beginscan(attrdef, AttrDefaultIndexId, true,
|
||||
NULL, 2, keys);
|
||||
|
||||
if (HeapTupleIsValid(tup = systable_getnext(scan)))
|
||||
{
|
||||
Form_pg_attrdef atdform = (Form_pg_attrdef) GETSTRUCT(tup);
|
||||
|
||||
result = atdform->oid;
|
||||
}
|
||||
|
||||
systable_endscan(scan);
|
||||
table_close(attrdef, AccessShareLock);
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
/*
|
||||
* Given a pg_attrdef OID, return the relation OID and column number of
|
||||
* the owning column (represented as an ObjectAddress for convenience).
|
||||
*
|
||||
* Returns InvalidObjectAddress if there is no such pg_attrdef entry.
|
||||
*/
|
||||
ObjectAddress
|
||||
GetAttrDefaultColumnAddress(Oid attrdefoid)
|
||||
{
|
||||
ObjectAddress result = InvalidObjectAddress;
|
||||
Relation attrdef;
|
||||
ScanKeyData skey[1];
|
||||
SysScanDesc scan;
|
||||
HeapTuple tup;
|
||||
|
||||
attrdef = table_open(AttrDefaultRelationId, AccessShareLock);
|
||||
ScanKeyInit(&skey[0],
|
||||
Anum_pg_attrdef_oid,
|
||||
BTEqualStrategyNumber, F_OIDEQ,
|
||||
ObjectIdGetDatum(attrdefoid));
|
||||
scan = systable_beginscan(attrdef, AttrDefaultOidIndexId, true,
|
||||
NULL, 1, skey);
|
||||
|
||||
if (HeapTupleIsValid(tup = systable_getnext(scan)))
|
||||
{
|
||||
Form_pg_attrdef atdform = (Form_pg_attrdef) GETSTRUCT(tup);
|
||||
|
||||
result.classId = RelationRelationId;
|
||||
result.objectId = atdform->adrelid;
|
||||
result.objectSubId = atdform->adnum;
|
||||
}
|
||||
|
||||
systable_endscan(scan);
|
||||
table_close(attrdef, AccessShareLock);
|
||||
|
||||
return result;
|
||||
}
|
||||
@ -34,6 +34,7 @@
|
||||
#include "catalog/objectaccess.h"
|
||||
#include "catalog/partition.h"
|
||||
#include "catalog/pg_am.h"
|
||||
#include "catalog/pg_attrdef.h"
|
||||
#include "catalog/pg_collation.h"
|
||||
#include "catalog/pg_constraint.h"
|
||||
#include "catalog/pg_depend.h"
|
||||
|
||||
@ -117,10 +117,6 @@ extern List *AddRelationNewConstraints(Relation rel,
|
||||
extern void RelationClearMissing(Relation rel);
|
||||
extern void SetAttrMissing(Oid relid, char *attname, char *value);
|
||||
|
||||
extern Oid StoreAttrDefault(Relation rel, AttrNumber attnum,
|
||||
Node *expr, bool is_internal,
|
||||
bool add_column_mode);
|
||||
|
||||
extern Node *cookDefault(ParseState *pstate,
|
||||
Node *raw_default,
|
||||
Oid atttypid,
|
||||
@ -132,9 +128,7 @@ extern void DeleteRelationTuple(Oid relid);
|
||||
extern void DeleteAttributeTuples(Oid relid);
|
||||
extern void DeleteSystemAttributeTuples(Oid relid);
|
||||
extern void RemoveAttributeById(Oid relid, AttrNumber attnum);
|
||||
extern void RemoveAttrDefault(Oid relid, AttrNumber attnum,
|
||||
DropBehavior behavior, bool complain, bool internal);
|
||||
extern void RemoveAttrDefaultById(Oid attrdefId);
|
||||
|
||||
extern void CopyStatistics(Oid fromrelid, Oid torelid);
|
||||
extern void RemoveStatistics(Oid relid, AttrNumber attnum);
|
||||
|
||||
|
||||
@ -19,6 +19,7 @@
|
||||
#define PG_ATTRDEF_H
|
||||
|
||||
#include "catalog/genbki.h"
|
||||
#include "catalog/objectaddress.h"
|
||||
#include "catalog/pg_attrdef_d.h"
|
||||
|
||||
/* ----------------
|
||||
@ -54,4 +55,16 @@ DECLARE_UNIQUE_INDEX_PKEY(pg_attrdef_oid_index, 2657, AttrDefaultOidIndexId, on
|
||||
|
||||
DECLARE_FOREIGN_KEY((adrelid, adnum), pg_attribute, (attrelid, attnum));
|
||||
|
||||
|
||||
extern Oid StoreAttrDefault(Relation rel, AttrNumber attnum,
|
||||
Node *expr, bool is_internal,
|
||||
bool add_column_mode);
|
||||
extern void RemoveAttrDefault(Oid relid, AttrNumber attnum,
|
||||
DropBehavior behavior,
|
||||
bool complain, bool internal);
|
||||
extern void RemoveAttrDefaultById(Oid attrdefId);
|
||||
|
||||
extern Oid GetAttrDefaultOid(Oid relid, AttrNumber attnum);
|
||||
extern ObjectAddress GetAttrDefaultColumnAddress(Oid attrdefoid);
|
||||
|
||||
#endif /* PG_ATTRDEF_H */
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user