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postgresql/src/backend/catalog/heap.c

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/*-------------------------------------------------------------------------
*
* heap.c
* code to create and destroy POSTGRES heap relations
*
* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/catalog/heap.c
*
*
* INTERFACE ROUTINES
* heap_create() - Create an uncataloged heap relation
* heap_create_with_catalog() - Create a cataloged relation
* heap_drop_with_catalog() - Removes named relation from catalogs
*
* NOTES
* this code taken from access/heap/create.c, which contains
* the old heap_create_with_catalog, amcreate, and amdestroy.
* those routines will soon call these routines using the function
* manager,
* just like the poorly named "NewXXX" routines do. The
* "New" routines are all going to die soon, once and for all!
* -cim 1/13/91
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/genam.h"
#include "access/htup_details.h"
#include "access/multixact.h"
#include "access/relation.h"
#include "access/sysattr.h"
#include "access/table.h"
#include "access/tableam.h"
#include "access/transam.h"
#include "access/xact.h"
#include "access/xlog.h"
#include "catalog/binary_upgrade.h"
#include "catalog/catalog.h"
#include "catalog/dependency.h"
#include "catalog/heap.h"
#include "catalog/index.h"
#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_foreign_table.h"
#include "catalog/pg_inherits.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_partitioned_table.h"
#include "catalog/pg_statistic.h"
#include "catalog/pg_subscription_rel.h"
#include "catalog/pg_tablespace.h"
#include "catalog/pg_type.h"
#include "catalog/storage.h"
#include "catalog/storage_xlog.h"
#include "commands/tablecmds.h"
#include "commands/typecmds.h"
#include "executor/executor.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/optimizer.h"
#include "parser/parse_coerce.h"
#include "parser/parse_collate.h"
#include "parser/parse_expr.h"
#include "parser/parse_relation.h"
#include "parser/parsetree.h"
#include "partitioning/partdesc.h"
#include "storage/lmgr.h"
#include "storage/predicate.h"
#include "storage/smgr.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/datum.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/partcache.h"
#include "utils/rel.h"
#include "utils/ruleutils.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
/* Potentially set by pg_upgrade_support functions */
Oid binary_upgrade_next_heap_pg_class_oid = InvalidOid;
Oid binary_upgrade_next_toast_pg_class_oid = InvalidOid;
static void AddNewRelationTuple(Relation pg_class_desc,
Relation new_rel_desc,
Oid new_rel_oid,
Oid new_type_oid,
Oid reloftype,
Oid relowner,
char relkind,
TransactionId relfrozenxid,
TransactionId relminmxid,
Datum relacl,
Datum reloptions);
static ObjectAddress AddNewRelationType(const char *typeName,
Oid typeNamespace,
Oid new_rel_oid,
char new_rel_kind,
Oid ownerid,
Oid new_row_type,
Oid new_array_type);
static void RelationRemoveInheritance(Oid relid);
static Oid StoreRelCheck(Relation rel, const char *ccname, Node *expr,
bool is_validated, bool is_local, int inhcount,
bool is_no_inherit, bool is_internal);
static void StoreConstraints(Relation rel, List *cooked_constraints,
bool is_internal);
static bool MergeWithExistingConstraint(Relation rel, const char *ccname, Node *expr,
bool allow_merge, bool is_local,
bool is_initially_valid,
bool is_no_inherit);
static void SetRelationNumChecks(Relation rel, int numchecks);
static Node *cookConstraint(ParseState *pstate,
Node *raw_constraint,
char *relname);
/* ----------------------------------------------------------------
* XXX UGLY HARD CODED BADNESS FOLLOWS XXX
*
* these should all be moved to someplace in the lib/catalog
* module, if not obliterated first.
* ----------------------------------------------------------------
*/
/*
* Note:
* Should the system special case these attributes in the future?
* Advantage: consume much less space in the ATTRIBUTE relation.
* Disadvantage: special cases will be all over the place.
*/
/*
* The initializers below do not include trailing variable length fields,
* but that's OK - we're never going to reference anything beyond the
* fixed-size portion of the structure anyway.
*/
static const FormData_pg_attribute a1 = {
.attname = {"ctid"},
.atttypid = TIDOID,
.attlen = sizeof(ItemPointerData),
.attnum = SelfItemPointerAttributeNumber,
.attcacheoff = -1,
.atttypmod = -1,
.attbyval = false,
.attstorage = 'p',
.attalign = 's',
.attnotnull = true,
.attislocal = true,
};
static const FormData_pg_attribute a2 = {
.attname = {"xmin"},
.atttypid = XIDOID,
.attlen = sizeof(TransactionId),
.attnum = MinTransactionIdAttributeNumber,
.attcacheoff = -1,
.atttypmod = -1,
.attbyval = true,
.attstorage = 'p',
.attalign = 'i',
.attnotnull = true,
.attislocal = true,
};
static const FormData_pg_attribute a3 = {
.attname = {"cmin"},
.atttypid = CIDOID,
.attlen = sizeof(CommandId),
.attnum = MinCommandIdAttributeNumber,
.attcacheoff = -1,
.atttypmod = -1,
.attbyval = true,
.attstorage = 'p',
.attalign = 'i',
.attnotnull = true,
.attislocal = true,
};
static const FormData_pg_attribute a4 = {
.attname = {"xmax"},
.atttypid = XIDOID,
.attlen = sizeof(TransactionId),
.attnum = MaxTransactionIdAttributeNumber,
.attcacheoff = -1,
.atttypmod = -1,
.attbyval = true,
.attstorage = 'p',
.attalign = 'i',
.attnotnull = true,
.attislocal = true,
};
static const FormData_pg_attribute a5 = {
.attname = {"cmax"},
.atttypid = CIDOID,
.attlen = sizeof(CommandId),
.attnum = MaxCommandIdAttributeNumber,
.attcacheoff = -1,
.atttypmod = -1,
.attbyval = true,
.attstorage = 'p',
.attalign = 'i',
.attnotnull = true,
.attislocal = true,
};
/*
* We decided to call this attribute "tableoid" rather than say
* "classoid" on the basis that in the future there may be more than one
* table of a particular class/type. In any case table is still the word
* used in SQL.
*/
static const FormData_pg_attribute a6 = {
.attname = {"tableoid"},
.atttypid = OIDOID,
.attlen = sizeof(Oid),
.attnum = TableOidAttributeNumber,
.attcacheoff = -1,
.atttypmod = -1,
.attbyval = true,
.attstorage = 'p',
.attalign = 'i',
.attnotnull = true,
.attislocal = true,
};
static const FormData_pg_attribute *SysAtt[] = {&a1, &a2, &a3, &a4, &a5, &a6};
/*
* This function returns a Form_pg_attribute pointer for a system attribute.
* Note that we elog if the presented attno is invalid, which would only
* happen if there's a problem upstream.
*/
const FormData_pg_attribute *
SystemAttributeDefinition(AttrNumber attno)
{
if (attno >= 0 || attno < -(int) lengthof(SysAtt))
elog(ERROR, "invalid system attribute number %d", attno);
return SysAtt[-attno - 1];
}
/*
* If the given name is a system attribute name, return a Form_pg_attribute
* pointer for a prototype definition. If not, return NULL.
*/
const FormData_pg_attribute *
SystemAttributeByName(const char *attname)
{
int j;
for (j = 0; j < (int) lengthof(SysAtt); j++)
{
const FormData_pg_attribute *att = SysAtt[j];
if (strcmp(NameStr(att->attname), attname) == 0)
return att;
}
return NULL;
}
/* ----------------------------------------------------------------
* XXX END OF UGLY HARD CODED BADNESS XXX
* ---------------------------------------------------------------- */
/* ----------------------------------------------------------------
* heap_create - Create an uncataloged heap relation
*
* Note API change: the caller must now always provide the OID
* to use for the relation. The relfilenode may (and, normally,
* should) be left unspecified.
*
* rel->rd_rel is initialized by RelationBuildLocalRelation,
* and is mostly zeroes at return.
* ----------------------------------------------------------------
*/
Relation
heap_create(const char *relname,
Oid relnamespace,
Oid reltablespace,
Oid relid,
Oid relfilenode,
Oid accessmtd,
TupleDesc tupDesc,
char relkind,
char relpersistence,
bool shared_relation,
bool mapped_relation,
bool allow_system_table_mods,
TransactionId *relfrozenxid,
MultiXactId *relminmxid)
{
bool create_storage;
Relation rel;
/* The caller must have provided an OID for the relation. */
Assert(OidIsValid(relid));
/*
* Don't allow creating relations in pg_catalog directly, even though it
* is allowed to move user defined relations there. Semantics with search
* paths including pg_catalog are too confusing for now.
*
* But allow creating indexes on relations in pg_catalog even if
* allow_system_table_mods = off, upper layers already guarantee it's on a
* user defined relation, not a system one.
*/
if (!allow_system_table_mods &&
((IsCatalogNamespace(relnamespace) && relkind != RELKIND_INDEX) ||
IsToastNamespace(relnamespace)) &&
IsNormalProcessingMode())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied to create \"%s.%s\"",
get_namespace_name(relnamespace), relname),
errdetail("System catalog modifications are currently disallowed.")));
*relfrozenxid = InvalidTransactionId;
*relminmxid = InvalidMultiXactId;
/* Handle reltablespace for specific relkinds. */
switch (relkind)
{
case RELKIND_VIEW:
case RELKIND_COMPOSITE_TYPE:
case RELKIND_FOREIGN_TABLE:
/*
* Force reltablespace to zero if the relation has no physical
* storage. This is mainly just for cleanliness' sake.
*
* Partitioned tables and indexes don't have physical storage
* either, but we want to keep their tablespace settings so that
* their children can inherit it.
*/
reltablespace = InvalidOid;
break;
case RELKIND_SEQUENCE:
/*
* Force reltablespace to zero for sequences, since we don't
* support moving them around into different tablespaces.
*/
reltablespace = InvalidOid;
break;
default:
break;
}
/*
* Decide whether to create storage. If caller passed a valid relfilenode,
* storage is already created, so don't do it here. Also don't create it
* for relkinds without physical storage.
*/
if (!RELKIND_HAS_STORAGE(relkind) || OidIsValid(relfilenode))
create_storage = false;
else
{
create_storage = true;
relfilenode = relid;
}
/*
* Never allow a pg_class entry to explicitly specify the database's
* default tablespace in reltablespace; force it to zero instead. This
* ensures that if the database is cloned with a different default
* tablespace, the pg_class entry will still match where CREATE DATABASE
* will put the physically copied relation.
*
* Yes, this is a bit of a hack.
*/
if (reltablespace == MyDatabaseTableSpace)
reltablespace = InvalidOid;
/*
* build the relcache entry.
*/
rel = RelationBuildLocalRelation(relname,
relnamespace,
tupDesc,
relid,
accessmtd,
relfilenode,
reltablespace,
shared_relation,
mapped_relation,
relpersistence,
relkind);
/*
* Have the storage manager create the relation's disk file, if needed.
*
* For relations the callback creates both the main and the init fork, for
* indexes only the main fork is created. The other forks will be created
* on demand.
*/
if (create_storage)
{
RelationOpenSmgr(rel);
switch (rel->rd_rel->relkind)
{
case RELKIND_VIEW:
case RELKIND_COMPOSITE_TYPE:
case RELKIND_FOREIGN_TABLE:
case RELKIND_PARTITIONED_TABLE:
case RELKIND_PARTITIONED_INDEX:
Assert(false);
break;
case RELKIND_INDEX:
case RELKIND_SEQUENCE:
RelationCreateStorage(rel->rd_node, relpersistence);
break;
case RELKIND_RELATION:
case RELKIND_TOASTVALUE:
case RELKIND_MATVIEW:
table_relation_set_new_filenode(rel, &rel->rd_node,
relpersistence,
relfrozenxid, relminmxid);
break;
}
}
return rel;
}
/* ----------------------------------------------------------------
* heap_create_with_catalog - Create a cataloged relation
*
* this is done in multiple steps:
*
* 1) CheckAttributeNamesTypes() is used to make certain the tuple
* descriptor contains a valid set of attribute names and types
*
* 2) pg_class is opened and get_relname_relid()
* performs a scan to ensure that no relation with the
* same name already exists.
*
* 3) heap_create() is called to create the new relation on disk.
*
* 4) TypeCreate() is called to define a new type corresponding
* to the new relation.
*
* 5) AddNewRelationTuple() is called to register the
* relation in pg_class.
*
* 6) AddNewAttributeTuples() is called to register the
* new relation's schema in pg_attribute.
*
* 7) StoreConstraints is called () - vadim 08/22/97
*
* 8) the relations are closed and the new relation's oid
* is returned.
*
* ----------------------------------------------------------------
*/
/* --------------------------------
* CheckAttributeNamesTypes
*
* this is used to make certain the tuple descriptor contains a
* valid set of attribute names and datatypes. a problem simply
* generates ereport(ERROR) which aborts the current transaction.
*
* relkind is the relkind of the relation to be created.
* flags controls which datatypes are allowed, cf CheckAttributeType.
* --------------------------------
*/
void
CheckAttributeNamesTypes(TupleDesc tupdesc, char relkind,
int flags)
{
int i;
int j;
int natts = tupdesc->natts;
/* Sanity check on column count */
if (natts < 0 || natts > MaxHeapAttributeNumber)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_COLUMNS),
errmsg("tables can have at most %d columns",
MaxHeapAttributeNumber)));
/*
* first check for collision with system attribute names
*
* Skip this for a view or type relation, since those don't have system
* attributes.
*/
if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE)
{
for (i = 0; i < natts; i++)
{
Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
if (SystemAttributeByName(NameStr(attr->attname)) != NULL)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column name \"%s\" conflicts with a system column name",
NameStr(attr->attname))));
}
}
/*
* next check for repeated attribute names
*/
for (i = 1; i < natts; i++)
{
for (j = 0; j < i; j++)
{
if (strcmp(NameStr(TupleDescAttr(tupdesc, j)->attname),
NameStr(TupleDescAttr(tupdesc, i)->attname)) == 0)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_COLUMN),
errmsg("column name \"%s\" specified more than once",
NameStr(TupleDescAttr(tupdesc, j)->attname))));
}
}
/*
* next check the attribute types
*/
for (i = 0; i < natts; i++)
{
CheckAttributeType(NameStr(TupleDescAttr(tupdesc, i)->attname),
TupleDescAttr(tupdesc, i)->atttypid,
TupleDescAttr(tupdesc, i)->attcollation,
NIL, /* assume we're creating a new rowtype */
flags);
}
}
/* --------------------------------
* CheckAttributeType
*
* Verify that the proposed datatype of an attribute is legal.
* This is needed mainly because there are types (and pseudo-types)
* in the catalogs that we do not support as elements of real tuples.
* We also check some other properties required of a table column.
*
* If the attribute is being proposed for addition to an existing table or
* composite type, pass a one-element list of the rowtype OID as
* containing_rowtypes. When checking a to-be-created rowtype, it's
* sufficient to pass NIL, because there could not be any recursive reference
* to a not-yet-existing rowtype.
*
* flags is a bitmask controlling which datatypes we allow. For the most
* part, pseudo-types are disallowed as attribute types, but there are some
* exceptions: ANYARRAYOID, RECORDOID, and RECORDARRAYOID can be allowed
* in some cases. (This works because values of those type classes are
* self-identifying to some extent. However, RECORDOID and RECORDARRAYOID
* are reliably identifiable only within a session, since the identity info
* may use a typmod that is only locally assigned. The caller is expected
* to know whether these cases are safe.)
* --------------------------------
*/
void
CheckAttributeType(const char *attname,
Oid atttypid, Oid attcollation,
List *containing_rowtypes,
int flags)
{
char att_typtype = get_typtype(atttypid);
Oid att_typelem;
if (att_typtype == TYPTYPE_PSEUDO)
{
/*
* We disallow pseudo-type columns, with the exception of ANYARRAY,
* RECORD, and RECORD[] when the caller says that those are OK.
*
* We don't need to worry about recursive containment for RECORD and
* RECORD[] because (a) no named composite type should be allowed to
* contain those, and (b) two "anonymous" record types couldn't be
* considered to be the same type, so infinite recursion isn't
* possible.
*/
if (!((atttypid == ANYARRAYOID && (flags & CHKATYPE_ANYARRAY)) ||
(atttypid == RECORDOID && (flags & CHKATYPE_ANYRECORD)) ||
(atttypid == RECORDARRAYOID && (flags & CHKATYPE_ANYRECORD))))
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("column \"%s\" has pseudo-type %s",
attname, format_type_be(atttypid))));
}
else if (att_typtype == TYPTYPE_DOMAIN)
{
/*
* If it's a domain, recurse to check its base type.
*/
CheckAttributeType(attname, getBaseType(atttypid), attcollation,
containing_rowtypes,
flags);
}
else if (att_typtype == TYPTYPE_COMPOSITE)
{
/*
* For a composite type, recurse into its attributes.
*/
Relation relation;
TupleDesc tupdesc;
int i;
/*
* Check for self-containment. Eventually we might be able to allow
* this (just return without complaint, if so) but it's not clear how
* many other places would require anti-recursion defenses before it
* would be safe to allow tables to contain their own rowtype.
*/
if (list_member_oid(containing_rowtypes, atttypid))
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("composite type %s cannot be made a member of itself",
format_type_be(atttypid))));
containing_rowtypes = lcons_oid(atttypid, containing_rowtypes);
relation = relation_open(get_typ_typrelid(atttypid), AccessShareLock);
tupdesc = RelationGetDescr(relation);
for (i = 0; i < tupdesc->natts; i++)
{
Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
if (attr->attisdropped)
continue;
CheckAttributeType(NameStr(attr->attname),
attr->atttypid, attr->attcollation,
containing_rowtypes,
flags);
}
relation_close(relation, AccessShareLock);
containing_rowtypes = list_delete_first(containing_rowtypes);
}
else if (OidIsValid((att_typelem = get_element_type(atttypid))))
{
/*
* Must recurse into array types, too, in case they are composite.
*/
CheckAttributeType(attname, att_typelem, attcollation,
containing_rowtypes,
flags);
}
/*
* This might not be strictly invalid per SQL standard, but it is pretty
* useless, and it cannot be dumped, so we must disallow it.
*/
if (!OidIsValid(attcollation) && type_is_collatable(atttypid))
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("no collation was derived for column \"%s\" with collatable type %s",
attname, format_type_be(atttypid)),
errhint("Use the COLLATE clause to set the collation explicitly.")));
}
/*
* InsertPgAttributeTuple
* Construct and insert a new tuple in pg_attribute.
*
* Caller has already opened and locked pg_attribute. new_attribute is the
* attribute to insert. attcacheoff is always initialized to -1, attacl and
* attoptions are always initialized to NULL.
*
* indstate is the index state for CatalogTupleInsertWithInfo. It can be
* passed as NULL, in which case we'll fetch the necessary info. (Don't do
* this when inserting multiple attributes, because it's a tad more
* expensive.)
*/
void
InsertPgAttributeTuple(Relation pg_attribute_rel,
Form_pg_attribute new_attribute,
CatalogIndexState indstate)
{
Datum values[Natts_pg_attribute];
bool nulls[Natts_pg_attribute];
HeapTuple tup;
/* This is a tad tedious, but way cleaner than what we used to do... */
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
values[Anum_pg_attribute_attrelid - 1] = ObjectIdGetDatum(new_attribute->attrelid);
values[Anum_pg_attribute_attname - 1] = NameGetDatum(&new_attribute->attname);
values[Anum_pg_attribute_atttypid - 1] = ObjectIdGetDatum(new_attribute->atttypid);
values[Anum_pg_attribute_attstattarget - 1] = Int32GetDatum(new_attribute->attstattarget);
values[Anum_pg_attribute_attlen - 1] = Int16GetDatum(new_attribute->attlen);
values[Anum_pg_attribute_attnum - 1] = Int16GetDatum(new_attribute->attnum);
values[Anum_pg_attribute_attndims - 1] = Int32GetDatum(new_attribute->attndims);
values[Anum_pg_attribute_attcacheoff - 1] = Int32GetDatum(-1);
values[Anum_pg_attribute_atttypmod - 1] = Int32GetDatum(new_attribute->atttypmod);
values[Anum_pg_attribute_attbyval - 1] = BoolGetDatum(new_attribute->attbyval);
values[Anum_pg_attribute_attstorage - 1] = CharGetDatum(new_attribute->attstorage);
values[Anum_pg_attribute_attalign - 1] = CharGetDatum(new_attribute->attalign);
values[Anum_pg_attribute_attnotnull - 1] = BoolGetDatum(new_attribute->attnotnull);
values[Anum_pg_attribute_atthasdef - 1] = BoolGetDatum(new_attribute->atthasdef);
values[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(new_attribute->atthasmissing);
values[Anum_pg_attribute_attidentity - 1] = CharGetDatum(new_attribute->attidentity);
values[Anum_pg_attribute_attgenerated - 1] = CharGetDatum(new_attribute->attgenerated);
values[Anum_pg_attribute_attisdropped - 1] = BoolGetDatum(new_attribute->attisdropped);
values[Anum_pg_attribute_attislocal - 1] = BoolGetDatum(new_attribute->attislocal);
values[Anum_pg_attribute_attinhcount - 1] = Int32GetDatum(new_attribute->attinhcount);
values[Anum_pg_attribute_attcollation - 1] = ObjectIdGetDatum(new_attribute->attcollation);
/* start out with empty permissions and empty options */
nulls[Anum_pg_attribute_attacl - 1] = true;
nulls[Anum_pg_attribute_attoptions - 1] = true;
nulls[Anum_pg_attribute_attfdwoptions - 1] = true;
nulls[Anum_pg_attribute_attmissingval - 1] = true;
tup = heap_form_tuple(RelationGetDescr(pg_attribute_rel), values, nulls);
/* finally insert the new tuple, update the indexes, and clean up */
if (indstate != NULL)
CatalogTupleInsertWithInfo(pg_attribute_rel, tup, indstate);
else
CatalogTupleInsert(pg_attribute_rel, tup);
heap_freetuple(tup);
}
/* --------------------------------
* AddNewAttributeTuples
*
* this registers the new relation's schema by adding
* tuples to pg_attribute.
* --------------------------------
*/
static void
AddNewAttributeTuples(Oid new_rel_oid,
TupleDesc tupdesc,
char relkind)
{
Form_pg_attribute attr;
int i;
Relation rel;
CatalogIndexState indstate;
int natts = tupdesc->natts;
ObjectAddress myself,
referenced;
/*
* open pg_attribute and its indexes.
*/
rel = table_open(AttributeRelationId, RowExclusiveLock);
indstate = CatalogOpenIndexes(rel);
/*
* First we add the user attributes. This is also a convenient place to
* add dependencies on their datatypes and collations.
*/
for (i = 0; i < natts; i++)
{
attr = TupleDescAttr(tupdesc, i);
/* Fill in the correct relation OID */
attr->attrelid = new_rel_oid;
/* Make sure this is OK, too */
attr->attstattarget = -1;
InsertPgAttributeTuple(rel, attr, indstate);
/* Add dependency info */
myself.classId = RelationRelationId;
myself.objectId = new_rel_oid;
myself.objectSubId = i + 1;
referenced.classId = TypeRelationId;
referenced.objectId = attr->atttypid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
/* The default collation is pinned, so don't bother recording it */
if (OidIsValid(attr->attcollation) &&
attr->attcollation != DEFAULT_COLLATION_OID)
{
referenced.classId = CollationRelationId;
referenced.objectId = attr->attcollation;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
}
/*
* Next we add the system attributes. Skip OID if rel has no OIDs. Skip
* all for a view or type relation. We don't bother with making datatype
* dependencies here, since presumably all these types are pinned.
*/
if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE)
{
for (i = 0; i < (int) lengthof(SysAtt); i++)
{
FormData_pg_attribute attStruct;
memcpy(&attStruct, SysAtt[i], sizeof(FormData_pg_attribute));
/* Fill in the correct relation OID in the copied tuple */
attStruct.attrelid = new_rel_oid;
InsertPgAttributeTuple(rel, &attStruct, indstate);
}
}
/*
* clean up
*/
CatalogCloseIndexes(indstate);
table_close(rel, RowExclusiveLock);
}
/* --------------------------------
* InsertPgClassTuple
*
* Construct and insert a new tuple in pg_class.
*
* Caller has already opened and locked pg_class.
* Tuple data is taken from new_rel_desc->rd_rel, except for the
* variable-width fields which are not present in a cached reldesc.
* relacl and reloptions are passed in Datum form (to avoid having
* to reference the data types in heap.h). Pass (Datum) 0 to set them
* to NULL.
* --------------------------------
*/
void
InsertPgClassTuple(Relation pg_class_desc,
Relation new_rel_desc,
Oid new_rel_oid,
Datum relacl,
Datum reloptions)
{
Form_pg_class rd_rel = new_rel_desc->rd_rel;
Datum values[Natts_pg_class];
bool nulls[Natts_pg_class];
HeapTuple tup;
/* This is a tad tedious, but way cleaner than what we used to do... */
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
values[Anum_pg_class_oid - 1] = ObjectIdGetDatum(new_rel_oid);
values[Anum_pg_class_relname - 1] = NameGetDatum(&rd_rel->relname);
values[Anum_pg_class_relnamespace - 1] = ObjectIdGetDatum(rd_rel->relnamespace);
values[Anum_pg_class_reltype - 1] = ObjectIdGetDatum(rd_rel->reltype);
values[Anum_pg_class_reloftype - 1] = ObjectIdGetDatum(rd_rel->reloftype);
values[Anum_pg_class_relowner - 1] = ObjectIdGetDatum(rd_rel->relowner);
values[Anum_pg_class_relam - 1] = ObjectIdGetDatum(rd_rel->relam);
values[Anum_pg_class_relfilenode - 1] = ObjectIdGetDatum(rd_rel->relfilenode);
values[Anum_pg_class_reltablespace - 1] = ObjectIdGetDatum(rd_rel->reltablespace);
values[Anum_pg_class_relpages - 1] = Int32GetDatum(rd_rel->relpages);
values[Anum_pg_class_reltuples - 1] = Float4GetDatum(rd_rel->reltuples);
values[Anum_pg_class_relallvisible - 1] = Int32GetDatum(rd_rel->relallvisible);
values[Anum_pg_class_reltoastrelid - 1] = ObjectIdGetDatum(rd_rel->reltoastrelid);
values[Anum_pg_class_relhasindex - 1] = BoolGetDatum(rd_rel->relhasindex);
values[Anum_pg_class_relisshared - 1] = BoolGetDatum(rd_rel->relisshared);
values[Anum_pg_class_relpersistence - 1] = CharGetDatum(rd_rel->relpersistence);
values[Anum_pg_class_relkind - 1] = CharGetDatum(rd_rel->relkind);
values[Anum_pg_class_relnatts - 1] = Int16GetDatum(rd_rel->relnatts);
values[Anum_pg_class_relchecks - 1] = Int16GetDatum(rd_rel->relchecks);
values[Anum_pg_class_relhasrules - 1] = BoolGetDatum(rd_rel->relhasrules);
values[Anum_pg_class_relhastriggers - 1] = BoolGetDatum(rd_rel->relhastriggers);
values[Anum_pg_class_relrowsecurity - 1] = BoolGetDatum(rd_rel->relrowsecurity);
values[Anum_pg_class_relforcerowsecurity - 1] = BoolGetDatum(rd_rel->relforcerowsecurity);
values[Anum_pg_class_relhassubclass - 1] = BoolGetDatum(rd_rel->relhassubclass);
values[Anum_pg_class_relispopulated - 1] = BoolGetDatum(rd_rel->relispopulated);
values[Anum_pg_class_relreplident - 1] = CharGetDatum(rd_rel->relreplident);
values[Anum_pg_class_relispartition - 1] = BoolGetDatum(rd_rel->relispartition);
values[Anum_pg_class_relrewrite - 1] = ObjectIdGetDatum(rd_rel->relrewrite);
values[Anum_pg_class_relfrozenxid - 1] = TransactionIdGetDatum(rd_rel->relfrozenxid);
values[Anum_pg_class_relminmxid - 1] = MultiXactIdGetDatum(rd_rel->relminmxid);
if (relacl != (Datum) 0)
values[Anum_pg_class_relacl - 1] = relacl;
else
nulls[Anum_pg_class_relacl - 1] = true;
if (reloptions != (Datum) 0)
values[Anum_pg_class_reloptions - 1] = reloptions;
else
nulls[Anum_pg_class_reloptions - 1] = true;
/* relpartbound is set by updating this tuple, if necessary */
nulls[Anum_pg_class_relpartbound - 1] = true;
tup = heap_form_tuple(RelationGetDescr(pg_class_desc), values, nulls);
/* finally insert the new tuple, update the indexes, and clean up */
CatalogTupleInsert(pg_class_desc, tup);
heap_freetuple(tup);
}
/* --------------------------------
* AddNewRelationTuple
*
* this registers the new relation in the catalogs by
* adding a tuple to pg_class.
* --------------------------------
*/
static void
AddNewRelationTuple(Relation pg_class_desc,
Relation new_rel_desc,
Oid new_rel_oid,
Oid new_type_oid,
Oid reloftype,
Oid relowner,
char relkind,
TransactionId relfrozenxid,
TransactionId relminmxid,
Datum relacl,
Datum reloptions)
{
Form_pg_class new_rel_reltup;
/*
* first we update some of the information in our uncataloged relation's
* relation descriptor.
*/
new_rel_reltup = new_rel_desc->rd_rel;
switch (relkind)
{
case RELKIND_RELATION:
case RELKIND_MATVIEW:
case RELKIND_INDEX:
case RELKIND_TOASTVALUE:
/* The relation is real, but as yet empty */
new_rel_reltup->relpages = 0;
new_rel_reltup->reltuples = 0;
new_rel_reltup->relallvisible = 0;
break;
case RELKIND_SEQUENCE:
/* Sequences always have a known size */
new_rel_reltup->relpages = 1;
new_rel_reltup->reltuples = 1;
new_rel_reltup->relallvisible = 0;
break;
default:
/* Views, etc, have no disk storage */
new_rel_reltup->relpages = 0;
new_rel_reltup->reltuples = 0;
new_rel_reltup->relallvisible = 0;
break;
}
new_rel_reltup->relfrozenxid = relfrozenxid;
new_rel_reltup->relminmxid = relminmxid;
new_rel_reltup->relowner = relowner;
new_rel_reltup->reltype = new_type_oid;
new_rel_reltup->reloftype = reloftype;
/* relispartition is always set by updating this tuple later */
new_rel_reltup->relispartition = false;
new_rel_desc->rd_att->tdtypeid = new_type_oid;
/* Now build and insert the tuple */
InsertPgClassTuple(pg_class_desc, new_rel_desc, new_rel_oid,
relacl, reloptions);
}
/* --------------------------------
* AddNewRelationType -
*
* define a composite type corresponding to the new relation
* --------------------------------
*/
static ObjectAddress
AddNewRelationType(const char *typeName,
Oid typeNamespace,
Oid new_rel_oid,
char new_rel_kind,
Oid ownerid,
Oid new_row_type,
Oid new_array_type)
{
return
TypeCreate(new_row_type, /* optional predetermined OID */
typeName, /* type name */
typeNamespace, /* type namespace */
new_rel_oid, /* relation oid */
new_rel_kind, /* relation kind */
ownerid, /* owner's ID */
-1, /* internal size (varlena) */
TYPTYPE_COMPOSITE, /* type-type (composite) */
TYPCATEGORY_COMPOSITE, /* type-category (ditto) */
false, /* composite types are never preferred */
DEFAULT_TYPDELIM, /* default array delimiter */
F_RECORD_IN, /* input procedure */
F_RECORD_OUT, /* output procedure */
F_RECORD_RECV, /* receive procedure */
F_RECORD_SEND, /* send procedure */
InvalidOid, /* typmodin procedure - none */
InvalidOid, /* typmodout procedure - none */
InvalidOid, /* analyze procedure - default */
InvalidOid, /* array element type - irrelevant */
false, /* this is not an array type */
new_array_type, /* array type if any */
InvalidOid, /* domain base type - irrelevant */
NULL, /* default value - none */
NULL, /* default binary representation */
false, /* passed by reference */
'd', /* alignment - must be the largest! */
'x', /* fully TOASTable */
-1, /* typmod */
0, /* array dimensions for typBaseType */
false, /* Type NOT NULL */
InvalidOid); /* rowtypes never have a collation */
}
/* --------------------------------
* heap_create_with_catalog
*
* creates a new cataloged relation. see comments above.
*
* Arguments:
* relname: name to give to new rel
* relnamespace: OID of namespace it goes in
* reltablespace: OID of tablespace it goes in
* relid: OID to assign to new rel, or InvalidOid to select a new OID
* reltypeid: OID to assign to rel's rowtype, or InvalidOid to select one
* reloftypeid: if a typed table, OID of underlying type; else InvalidOid
* ownerid: OID of new rel's owner
* tupdesc: tuple descriptor (source of column definitions)
* cooked_constraints: list of precooked check constraints and defaults
* relkind: relkind for new rel
* relpersistence: rel's persistence status (permanent, temp, or unlogged)
* shared_relation: true if it's to be a shared relation
* mapped_relation: true if the relation will use the relfilenode map
* oncommit: ON COMMIT marking (only relevant if it's a temp table)
* reloptions: reloptions in Datum form, or (Datum) 0 if none
* use_user_acl: true if should look for user-defined default permissions;
* if false, relacl is always set NULL
* allow_system_table_mods: true to allow creation in system namespaces
* is_internal: is this a system-generated catalog?
*
* Output parameters:
* typaddress: if not null, gets the object address of the new pg_type entry
*
* Returns the OID of the new relation
* --------------------------------
*/
Oid
heap_create_with_catalog(const char *relname,
Oid relnamespace,
Oid reltablespace,
Oid relid,
Oid reltypeid,
Oid reloftypeid,
Oid ownerid,
Oid accessmtd,
TupleDesc tupdesc,
List *cooked_constraints,
char relkind,
char relpersistence,
bool shared_relation,
bool mapped_relation,
OnCommitAction oncommit,
Datum reloptions,
bool use_user_acl,
bool allow_system_table_mods,
bool is_internal,
Oid relrewrite,
ObjectAddress *typaddress)
{
Relation pg_class_desc;
Relation new_rel_desc;
Acl *relacl;
Oid existing_relid;
Oid old_type_oid;
Oid new_type_oid;
ObjectAddress new_type_addr;
Oid new_array_oid = InvalidOid;
TransactionId relfrozenxid;
MultiXactId relminmxid;
pg_class_desc = table_open(RelationRelationId, RowExclusiveLock);
/*
* sanity checks
*/
Assert(IsNormalProcessingMode() || IsBootstrapProcessingMode());
/*
* Validate proposed tupdesc for the desired relkind. If
* allow_system_table_mods is on, allow ANYARRAY to be used; this is a
* hack to allow creating pg_statistic and cloning it during VACUUM FULL.
*/
CheckAttributeNamesTypes(tupdesc, relkind,
allow_system_table_mods ? CHKATYPE_ANYARRAY : 0);
/*
* This would fail later on anyway, if the relation already exists. But
* by catching it here we can emit a nicer error message.
*/
existing_relid = get_relname_relid(relname, relnamespace);
if (existing_relid != InvalidOid)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
errmsg("relation \"%s\" already exists", relname)));
/*
* Since we are going to create a rowtype as well, also check for
* collision with an existing type name. If there is one and it's an
* autogenerated array, we can rename it out of the way; otherwise we can
* at least give a good error message.
*/
old_type_oid = GetSysCacheOid2(TYPENAMENSP, Anum_pg_type_oid,
CStringGetDatum(relname),
ObjectIdGetDatum(relnamespace));
if (OidIsValid(old_type_oid))
{
if (!moveArrayTypeName(old_type_oid, relname, relnamespace))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("type \"%s\" already exists", relname),
errhint("A relation has an associated type of the same name, "
"so you must use a name that doesn't conflict "
"with any existing type.")));
}
/*
* Shared relations must be in pg_global (last-ditch check)
*/
if (shared_relation && reltablespace != GLOBALTABLESPACE_OID)
elog(ERROR, "shared relations must be placed in pg_global tablespace");
/*
* Allocate an OID for the relation, unless we were told what to use.
*
* The OID will be the relfilenode as well, so make sure it doesn't
* collide with either pg_class OIDs or existing physical files.
*/
if (!OidIsValid(relid))
{
/* Use binary-upgrade override for pg_class.oid/relfilenode? */
if (IsBinaryUpgrade &&
(relkind == RELKIND_RELATION || relkind == RELKIND_SEQUENCE ||
relkind == RELKIND_VIEW || relkind == RELKIND_MATVIEW ||
relkind == RELKIND_COMPOSITE_TYPE || relkind == RELKIND_FOREIGN_TABLE ||
relkind == RELKIND_PARTITIONED_TABLE))
{
if (!OidIsValid(binary_upgrade_next_heap_pg_class_oid))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("pg_class heap OID value not set when in binary upgrade mode")));
relid = binary_upgrade_next_heap_pg_class_oid;
binary_upgrade_next_heap_pg_class_oid = InvalidOid;
}
/* There might be no TOAST table, so we have to test for it. */
else if (IsBinaryUpgrade &&
OidIsValid(binary_upgrade_next_toast_pg_class_oid) &&
relkind == RELKIND_TOASTVALUE)
{
relid = binary_upgrade_next_toast_pg_class_oid;
binary_upgrade_next_toast_pg_class_oid = InvalidOid;
}
else
relid = GetNewRelFileNode(reltablespace, pg_class_desc,
relpersistence);
}
/*
* Determine the relation's initial permissions.
*/
if (use_user_acl)
{
switch (relkind)
{
case RELKIND_RELATION:
case RELKIND_VIEW:
case RELKIND_MATVIEW:
case RELKIND_FOREIGN_TABLE:
case RELKIND_PARTITIONED_TABLE:
relacl = get_user_default_acl(OBJECT_TABLE, ownerid,
relnamespace);
break;
case RELKIND_SEQUENCE:
relacl = get_user_default_acl(OBJECT_SEQUENCE, ownerid,
relnamespace);
break;
default:
relacl = NULL;
break;
}
}
else
relacl = NULL;
/*
* Create the relcache entry (mostly dummy at this point) and the physical
* disk file. (If we fail further down, it's the smgr's responsibility to
* remove the disk file again.)
*/
new_rel_desc = heap_create(relname,
relnamespace,
reltablespace,
relid,
InvalidOid,
accessmtd,
tupdesc,
relkind,
relpersistence,
shared_relation,
mapped_relation,
allow_system_table_mods,
&relfrozenxid,
&relminmxid);
Assert(relid == RelationGetRelid(new_rel_desc));
new_rel_desc->rd_rel->relrewrite = relrewrite;
/*
* Decide whether to create an array type over the relation's rowtype. We
* do not create any array types for system catalogs (ie, those made
* during initdb). We do not create them where the use of a relation as
* such is an implementation detail: toast tables, sequences and indexes.
*/
if (IsUnderPostmaster && (relkind == RELKIND_RELATION ||
relkind == RELKIND_VIEW ||
relkind == RELKIND_MATVIEW ||
relkind == RELKIND_FOREIGN_TABLE ||
relkind == RELKIND_COMPOSITE_TYPE ||
relkind == RELKIND_PARTITIONED_TABLE))
new_array_oid = AssignTypeArrayOid();
/*
* Since defining a relation also defines a complex type, we add a new
* system type corresponding to the new relation. The OID of the type can
* be preselected by the caller, but if reltypeid is InvalidOid, we'll
* generate a new OID for it.
*
* NOTE: we could get a unique-index failure here, in case someone else is
* creating the same type name in parallel but hadn't committed yet when
* we checked for a duplicate name above.
*/
new_type_addr = AddNewRelationType(relname,
relnamespace,
relid,
relkind,
ownerid,
reltypeid,
new_array_oid);
new_type_oid = new_type_addr.objectId;
if (typaddress)
*typaddress = new_type_addr;
/*
* Now make the array type if wanted.
*/
if (OidIsValid(new_array_oid))
{
char *relarrayname;
relarrayname = makeArrayTypeName(relname, relnamespace);
TypeCreate(new_array_oid, /* force the type's OID to this */
relarrayname, /* Array type name */
relnamespace, /* Same namespace as parent */
InvalidOid, /* Not composite, no relationOid */
0, /* relkind, also N/A here */
ownerid, /* owner's ID */
-1, /* Internal size (varlena) */
TYPTYPE_BASE, /* Not composite - typelem is */
TYPCATEGORY_ARRAY, /* type-category (array) */
false, /* array types are never preferred */
DEFAULT_TYPDELIM, /* default array delimiter */
F_ARRAY_IN, /* array input proc */
F_ARRAY_OUT, /* array output proc */
F_ARRAY_RECV, /* array recv (bin) proc */
F_ARRAY_SEND, /* array send (bin) proc */
InvalidOid, /* typmodin procedure - none */
InvalidOid, /* typmodout procedure - none */
F_ARRAY_TYPANALYZE, /* array analyze procedure */
new_type_oid, /* array element type - the rowtype */
true, /* yes, this is an array type */
InvalidOid, /* this has no array type */
InvalidOid, /* domain base type - irrelevant */
NULL, /* default value - none */
NULL, /* default binary representation */
false, /* passed by reference */
'd', /* alignment - must be the largest! */
'x', /* fully TOASTable */
-1, /* typmod */
0, /* array dimensions for typBaseType */
false, /* Type NOT NULL */
InvalidOid); /* rowtypes never have a collation */
pfree(relarrayname);
}
/*
* now create an entry in pg_class for the relation.
*
* NOTE: we could get a unique-index failure here, in case someone else is
* creating the same relation name in parallel but hadn't committed yet
* when we checked for a duplicate name above.
*/
AddNewRelationTuple(pg_class_desc,
new_rel_desc,
relid,
new_type_oid,
reloftypeid,
ownerid,
relkind,
relfrozenxid,
relminmxid,
PointerGetDatum(relacl),
reloptions);
/*
* now add tuples to pg_attribute for the attributes in our new relation.
*/
AddNewAttributeTuples(relid, new_rel_desc->rd_att, relkind);
/*
* Make a dependency link to force the relation to be deleted if its
* namespace is. Also make a dependency link to its owner, as well as
* dependencies for any roles mentioned in the default ACL.
*
* For composite types, these dependencies are tracked for the pg_type
* entry, so we needn't record them here. Likewise, TOAST tables don't
* need a namespace dependency (they live in a pinned namespace) nor an
* owner dependency (they depend indirectly through the parent table), nor
* should they have any ACL entries. The same applies for extension
* dependencies.
*
* Also, skip this in bootstrap mode, since we don't make dependencies
* while bootstrapping.
*/
if (relkind != RELKIND_COMPOSITE_TYPE &&
relkind != RELKIND_TOASTVALUE &&
!IsBootstrapProcessingMode())
{
ObjectAddress myself,
referenced;
myself.classId = RelationRelationId;
myself.objectId = relid;
myself.objectSubId = 0;
referenced.classId = NamespaceRelationId;
referenced.objectId = relnamespace;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
recordDependencyOnOwner(RelationRelationId, relid, ownerid);
recordDependencyOnNewAcl(RelationRelationId, relid, 0, ownerid, relacl);
recordDependencyOnCurrentExtension(&myself, false);
if (reloftypeid)
{
referenced.classId = TypeRelationId;
referenced.objectId = reloftypeid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
/*
* Make a dependency link to force the relation to be deleted if its
* access method is. Do this only for relation and materialized views.
*
* No need to add an explicit dependency for the toast table, as the
* main table depends on it.
*/
if (relkind == RELKIND_RELATION ||
relkind == RELKIND_MATVIEW)
{
referenced.classId = AccessMethodRelationId;
referenced.objectId = accessmtd;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
}
/* Post creation hook for new relation */
InvokeObjectPostCreateHookArg(RelationRelationId, relid, 0, is_internal);
/*
* Store any supplied constraints and defaults.
*
* NB: this may do a CommandCounterIncrement and rebuild the relcache
* entry, so the relation must be valid and self-consistent at this point.
* In particular, there are not yet constraints and defaults anywhere.
*/
StoreConstraints(new_rel_desc, cooked_constraints, is_internal);
/*
* If there's a special on-commit action, remember it
*/
if (oncommit != ONCOMMIT_NOOP)
register_on_commit_action(relid, oncommit);
/*
* ok, the relation has been cataloged, so close our relations and return
* the OID of the newly created relation.
*/
table_close(new_rel_desc, NoLock); /* do not unlock till end of xact */
table_close(pg_class_desc, RowExclusiveLock);
return relid;
}
/*
* RelationRemoveInheritance
*
* Formerly, this routine checked for child relations and aborted the
* deletion if any were found. Now we rely on the dependency mechanism
* to check for or delete child relations. By the time we get here,
* there are no children and we need only remove any pg_inherits rows
* linking this relation to its parent(s).
*/
static void
RelationRemoveInheritance(Oid relid)
{
Relation catalogRelation;
SysScanDesc scan;
ScanKeyData key;
HeapTuple tuple;
catalogRelation = table_open(InheritsRelationId, RowExclusiveLock);
ScanKeyInit(&key,
Anum_pg_inherits_inhrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
scan = systable_beginscan(catalogRelation, InheritsRelidSeqnoIndexId, true,
NULL, 1, &key);
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
CatalogTupleDelete(catalogRelation, &tuple->t_self);
systable_endscan(scan);
table_close(catalogRelation, RowExclusiveLock);
}
/*
* DeleteRelationTuple
*
* Remove pg_class row for the given relid.
*
* Note: this is shared by relation deletion and index deletion. It's
* not intended for use anyplace else.
*/
void
DeleteRelationTuple(Oid relid)
{
Relation pg_class_desc;
HeapTuple tup;
/* Grab an appropriate lock on the pg_class relation */
pg_class_desc = table_open(RelationRelationId, RowExclusiveLock);
tup = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for relation %u", relid);
/* delete the relation tuple from pg_class, and finish up */
CatalogTupleDelete(pg_class_desc, &tup->t_self);
ReleaseSysCache(tup);
table_close(pg_class_desc, RowExclusiveLock);
}
/*
* DeleteAttributeTuples
*
* Remove pg_attribute rows for the given relid.
*
* Note: this is shared by relation deletion and index deletion. It's
* not intended for use anyplace else.
*/
void
DeleteAttributeTuples(Oid relid)
{
Relation attrel;
SysScanDesc scan;
ScanKeyData key[1];
HeapTuple atttup;
/* Grab an appropriate lock on the pg_attribute relation */
attrel = table_open(AttributeRelationId, RowExclusiveLock);
/* Use the index to scan only attributes of the target relation */
ScanKeyInit(&key[0],
Anum_pg_attribute_attrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
scan = systable_beginscan(attrel, AttributeRelidNumIndexId, true,
NULL, 1, key);
/* Delete all the matching tuples */
while ((atttup = systable_getnext(scan)) != NULL)
CatalogTupleDelete(attrel, &atttup->t_self);
/* Clean up after the scan */
systable_endscan(scan);
table_close(attrel, RowExclusiveLock);
}
/*
* DeleteSystemAttributeTuples
*
* Remove pg_attribute rows for system columns of the given relid.
*
* Note: this is only used when converting a table to a view. Views don't
* have system columns, so we should remove them from pg_attribute.
*/
void
DeleteSystemAttributeTuples(Oid relid)
{
Relation attrel;
SysScanDesc scan;
ScanKeyData key[2];
HeapTuple atttup;
/* Grab an appropriate lock on the pg_attribute relation */
attrel = table_open(AttributeRelationId, RowExclusiveLock);
/* Use the index to scan only system attributes of the target relation */
ScanKeyInit(&key[0],
Anum_pg_attribute_attrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
ScanKeyInit(&key[1],
Anum_pg_attribute_attnum,
BTLessEqualStrategyNumber, F_INT2LE,
Int16GetDatum(0));
scan = systable_beginscan(attrel, AttributeRelidNumIndexId, true,
NULL, 2, key);
/* Delete all the matching tuples */
while ((atttup = systable_getnext(scan)) != NULL)
CatalogTupleDelete(attrel, &atttup->t_self);
/* Clean up after the scan */
systable_endscan(scan);
table_close(attrel, RowExclusiveLock);
}
/*
* RemoveAttributeById
*
* This is the guts of ALTER TABLE DROP COLUMN: actually mark the attribute
* deleted in pg_attribute. We also remove pg_statistic entries for it.
* (Everything else needed, such as getting rid of any pg_attrdef entry,
* is handled by dependency.c.)
*/
void
RemoveAttributeById(Oid relid, AttrNumber attnum)
{
Relation rel;
Relation attr_rel;
HeapTuple tuple;
Form_pg_attribute attStruct;
char newattname[NAMEDATALEN];
/*
* Grab an exclusive lock on the target table, which we will NOT release
* until end of transaction. (In the simple case where we are directly
* dropping this column, ATExecDropColumn already did this ... but when
* cascading from a drop of some other object, we may not have any lock.)
*/
rel = relation_open(relid, AccessExclusiveLock);
attr_rel = table_open(AttributeRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy2(ATTNUM,
ObjectIdGetDatum(relid),
Int16GetDatum(attnum));
if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
elog(ERROR, "cache lookup failed for attribute %d of relation %u",
attnum, relid);
attStruct = (Form_pg_attribute) GETSTRUCT(tuple);
if (attnum < 0)
{
/* System attribute (probably OID) ... just delete the row */
CatalogTupleDelete(attr_rel, &tuple->t_self);
}
else
{
/* Dropping user attributes is lots harder */
/* Mark the attribute as dropped */
attStruct->attisdropped = true;
/*
* Set the type OID to invalid. A dropped attribute's type link
* cannot be relied on (once the attribute is dropped, the type might
* be too). Fortunately we do not need the type row --- the only
* really essential information is the type's typlen and typalign,
* which are preserved in the attribute's attlen and attalign. We set
* atttypid to zero here as a means of catching code that incorrectly
* expects it to be valid.
*/
attStruct->atttypid = InvalidOid;
/* Remove any NOT NULL constraint the column may have */
attStruct->attnotnull = false;
/* We don't want to keep stats for it anymore */
attStruct->attstattarget = 0;
/* Unset this so no one tries to look up the generation expression */
attStruct->attgenerated = '\0';
/*
* Change the column name to something that isn't likely to conflict
*/
snprintf(newattname, sizeof(newattname),
"........pg.dropped.%d........", attnum);
namestrcpy(&(attStruct->attname), newattname);
/* clear the missing value if any */
if (attStruct->atthasmissing)
{
Datum valuesAtt[Natts_pg_attribute];
bool nullsAtt[Natts_pg_attribute];
bool replacesAtt[Natts_pg_attribute];
/* update the tuple - set atthasmissing and attmissingval */
MemSet(valuesAtt, 0, sizeof(valuesAtt));
MemSet(nullsAtt, false, sizeof(nullsAtt));
MemSet(replacesAtt, false, sizeof(replacesAtt));
valuesAtt[Anum_pg_attribute_atthasmissing - 1] =
BoolGetDatum(false);
replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
valuesAtt[Anum_pg_attribute_attmissingval - 1] = (Datum) 0;
nullsAtt[Anum_pg_attribute_attmissingval - 1] = true;
replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;
tuple = heap_modify_tuple(tuple, RelationGetDescr(attr_rel),
valuesAtt, nullsAtt, replacesAtt);
}
CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);
}
/*
* Because updating the pg_attribute row will trigger a relcache flush for
* the target relation, we need not do anything else to notify other
* backends of the change.
*/
table_close(attr_rel, RowExclusiveLock);
if (attnum > 0)
RemoveStatistics(relid, attnum);
relation_close(rel, NoLock);
}
/*
* 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);
}
/*
* heap_drop_with_catalog - removes specified relation from catalogs
*
* Note that this routine is not responsible for dropping objects that are
* linked to the pg_class entry via dependencies (for example, indexes and
* constraints). Those are deleted by the dependency-tracing logic in
* dependency.c before control gets here. In general, therefore, this routine
* should never be called directly; go through performDeletion() instead.
*/
void
heap_drop_with_catalog(Oid relid)
{
Relation rel;
HeapTuple tuple;
Oid parentOid = InvalidOid,
defaultPartOid = InvalidOid;
/*
* To drop a partition safely, we must grab exclusive lock on its parent,
* because another backend might be about to execute a query on the parent
* table. If it relies on previously cached partition descriptor, then it
* could attempt to access the just-dropped relation as its partition. We
* must therefore take a table lock strong enough to prevent all queries
* on the table from proceeding until we commit and send out a
* shared-cache-inval notice that will make them update their partition
* descriptors.
*/
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u", relid);
if (((Form_pg_class) GETSTRUCT(tuple))->relispartition)
{
parentOid = get_partition_parent(relid);
LockRelationOid(parentOid, AccessExclusiveLock);
/*
* If this is not the default partition, dropping it will change the
* default partition's partition constraint, so we must lock it.
*/
defaultPartOid = get_default_partition_oid(parentOid);
if (OidIsValid(defaultPartOid) && relid != defaultPartOid)
LockRelationOid(defaultPartOid, AccessExclusiveLock);
}
ReleaseSysCache(tuple);
/*
* Open and lock the relation.
*/
rel = relation_open(relid, AccessExclusiveLock);
/*
* There can no longer be anyone *else* touching the relation, but we
* might still have open queries or cursors, or pending trigger events, in
* our own session.
*/
CheckTableNotInUse(rel, "DROP TABLE");
/*
* This effectively deletes all rows in the table, and may be done in a
* serializable transaction. In that case we must record a rw-conflict in
* to this transaction from each transaction holding a predicate lock on
* the table.
*/
CheckTableForSerializableConflictIn(rel);
/*
* Delete pg_foreign_table tuple first.
*/
if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
{
Relation rel;
HeapTuple tuple;
rel = table_open(ForeignTableRelationId, RowExclusiveLock);
tuple = SearchSysCache1(FOREIGNTABLEREL, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for foreign table %u", relid);
CatalogTupleDelete(rel, &tuple->t_self);
ReleaseSysCache(tuple);
table_close(rel, RowExclusiveLock);
}
/*
* If a partitioned table, delete the pg_partitioned_table tuple.
*/
if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
RemovePartitionKeyByRelId(relid);
/*
* If the relation being dropped is the default partition itself,
* invalidate its entry in pg_partitioned_table.
*/
if (relid == defaultPartOid)
update_default_partition_oid(parentOid, InvalidOid);
/*
* Schedule unlinking of the relation's physical files at commit.
*/
if (rel->rd_rel->relkind != RELKIND_VIEW &&
rel->rd_rel->relkind != RELKIND_COMPOSITE_TYPE &&
rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
{
RelationDropStorage(rel);
}
/*
* Close relcache entry, but *keep* AccessExclusiveLock on the relation
* until transaction commit. This ensures no one else will try to do
* something with the doomed relation.
*/
relation_close(rel, NoLock);
/*
* Remove any associated relation synchronization states.
*/
RemoveSubscriptionRel(InvalidOid, relid);
/*
* Forget any ON COMMIT action for the rel
*/
remove_on_commit_action(relid);
/*
* Flush the relation from the relcache. We want to do this before
* starting to remove catalog entries, just to be certain that no relcache
* entry rebuild will happen partway through. (That should not really
* matter, since we don't do CommandCounterIncrement here, but let's be
* safe.)
*/
RelationForgetRelation(relid);
/*
* remove inheritance information
*/
RelationRemoveInheritance(relid);
/*
* delete statistics
*/
RemoveStatistics(relid, 0);
/*
* delete attribute tuples
*/
DeleteAttributeTuples(relid);
/*
* delete relation tuple
*/
DeleteRelationTuple(relid);
if (OidIsValid(parentOid))
{
/*
* If this is not the default partition, the partition constraint of
* the default partition has changed to include the portion of the key
* space previously covered by the dropped partition.
*/
if (OidIsValid(defaultPartOid) && relid != defaultPartOid)
CacheInvalidateRelcacheByRelid(defaultPartOid);
/*
* Invalidate the parent's relcache so that the partition is no longer
* included in its partition descriptor.
*/
CacheInvalidateRelcacheByRelid(parentOid);
/* keep the lock */
}
}
/*
* RelationClearMissing
*
* Set atthasmissing and attmissingval to false/null for all attributes
* where they are currently set. This can be safely and usefully done if
* the table is rewritten (e.g. by VACUUM FULL or CLUSTER) where we know there
* are no rows left with less than a full complement of attributes.
*
* The caller must have an AccessExclusive lock on the relation.
*/
void
RelationClearMissing(Relation rel)
{
Relation attr_rel;
Oid relid = RelationGetRelid(rel);
int natts = RelationGetNumberOfAttributes(rel);
int attnum;
Datum repl_val[Natts_pg_attribute];
bool repl_null[Natts_pg_attribute];
bool repl_repl[Natts_pg_attribute];
Form_pg_attribute attrtuple;
HeapTuple tuple,
newtuple;
memset(repl_val, 0, sizeof(repl_val));
memset(repl_null, false, sizeof(repl_null));
memset(repl_repl, false, sizeof(repl_repl));
repl_val[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(false);
repl_null[Anum_pg_attribute_attmissingval - 1] = true;
repl_repl[Anum_pg_attribute_atthasmissing - 1] = true;
repl_repl[Anum_pg_attribute_attmissingval - 1] = true;
/* Get a lock on pg_attribute */
attr_rel = table_open(AttributeRelationId, RowExclusiveLock);
/* process each non-system attribute, including any dropped columns */
for (attnum = 1; attnum <= natts; attnum++)
{
tuple = SearchSysCache2(ATTNUM,
ObjectIdGetDatum(relid),
Int16GetDatum(attnum));
if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
elog(ERROR, "cache lookup failed for attribute %d of relation %u",
attnum, relid);
attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
/* ignore any where atthasmissing is not true */
if (attrtuple->atthasmissing)
{
newtuple = heap_modify_tuple(tuple, RelationGetDescr(attr_rel),
repl_val, repl_null, repl_repl);
CatalogTupleUpdate(attr_rel, &newtuple->t_self, newtuple);
heap_freetuple(newtuple);
}
ReleaseSysCache(tuple);
}
/*
* Our update of the pg_attribute rows will force a relcache rebuild, so
* there's nothing else to do here.
*/
table_close(attr_rel, RowExclusiveLock);
}
/*
* SetAttrMissing
*
* Set the missing value of a single attribute. This should only be used by
* binary upgrade. Takes an AccessExclusive lock on the relation owning the
* attribute.
*/
void
SetAttrMissing(Oid relid, char *attname, char *value)
{
Datum valuesAtt[Natts_pg_attribute];
bool nullsAtt[Natts_pg_attribute];
bool replacesAtt[Natts_pg_attribute];
Datum missingval;
Form_pg_attribute attStruct;
Relation attrrel,
tablerel;
HeapTuple atttup,
newtup;
/* lock the table the attribute belongs to */
tablerel = table_open(relid, AccessExclusiveLock);
/* Lock the attribute row and get the data */
attrrel = table_open(AttributeRelationId, RowExclusiveLock);
atttup = SearchSysCacheAttName(relid, attname);
if (!HeapTupleIsValid(atttup))
elog(ERROR, "cache lookup failed for attribute %s of relation %u",
attname, relid);
attStruct = (Form_pg_attribute) GETSTRUCT(atttup);
/* get an array value from the value string */
missingval = OidFunctionCall3(F_ARRAY_IN,
CStringGetDatum(value),
ObjectIdGetDatum(attStruct->atttypid),
Int32GetDatum(attStruct->atttypmod));
/* update the tuple - set atthasmissing and attmissingval */
MemSet(valuesAtt, 0, sizeof(valuesAtt));
MemSet(nullsAtt, false, sizeof(nullsAtt));
MemSet(replacesAtt, false, sizeof(replacesAtt));
valuesAtt[Anum_pg_attribute_atthasmissing - 1] = BoolGetDatum(true);
replacesAtt[Anum_pg_attribute_atthasmissing - 1] = true;
valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;
newtup = heap_modify_tuple(atttup, RelationGetDescr(attrrel),
valuesAtt, nullsAtt, replacesAtt);
CatalogTupleUpdate(attrrel, &newtup->t_self, newtup);
/* clean up */
ReleaseSysCache(atttup);
table_close(attrrel, RowExclusiveLock);
table_close(tablerel, AccessExclusiveLock);
}
/*
* 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 (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;
}
/*
* Store a check-constraint expression for the given relation.
*
* Caller is responsible for updating the count of constraints
* in the pg_class entry for the relation.
*
* The OID of the new constraint is returned.
*/
static Oid
StoreRelCheck(Relation rel, const char *ccname, Node *expr,
bool is_validated, bool is_local, int inhcount,
bool is_no_inherit, bool is_internal)
{
char *ccbin;
List *varList;
int keycount;
int16 *attNos;
Oid constrOid;
/*
* Flatten expression to string form for storage.
*/
ccbin = nodeToString(expr);
/*
* Find columns of rel that are used in expr
*
* NB: pull_var_clause is okay here only because we don't allow subselects
* in check constraints; it would fail to examine the contents of
* subselects.
*/
varList = pull_var_clause(expr, 0);
keycount = list_length(varList);
if (keycount > 0)
{
ListCell *vl;
int i = 0;
attNos = (int16 *) palloc(keycount * sizeof(int16));
foreach(vl, varList)
{
Var *var = (Var *) lfirst(vl);
int j;
for (j = 0; j < i; j++)
if (attNos[j] == var->varattno)
break;
if (j == i)
attNos[i++] = var->varattno;
}
keycount = i;
}
else
attNos = NULL;
/*
* Partitioned tables do not contain any rows themselves, so a NO INHERIT
* constraint makes no sense.
*/
if (is_no_inherit &&
rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot add NO INHERIT constraint to partitioned table \"%s\"",
RelationGetRelationName(rel))));
/*
* Create the Check Constraint
*/
constrOid =
CreateConstraintEntry(ccname, /* Constraint Name */
RelationGetNamespace(rel), /* namespace */
CONSTRAINT_CHECK, /* Constraint Type */
false, /* Is Deferrable */
false, /* Is Deferred */
is_validated,
InvalidOid, /* no parent constraint */
RelationGetRelid(rel), /* relation */
attNos, /* attrs in the constraint */
keycount, /* # key attrs in the constraint */
keycount, /* # total attrs in the constraint */
InvalidOid, /* not a domain constraint */
InvalidOid, /* no associated index */
InvalidOid, /* Foreign key fields */
NULL,
NULL,
NULL,
NULL,
0,
' ',
' ',
' ',
NULL, /* not an exclusion constraint */
expr, /* Tree form of check constraint */
ccbin, /* Binary form of check constraint */
is_local, /* conislocal */
inhcount, /* coninhcount */
is_no_inherit, /* connoinherit */
is_internal); /* internally constructed? */
pfree(ccbin);
return constrOid;
}
/*
* Store defaults and constraints (passed as a list of CookedConstraint).
*
* Each CookedConstraint struct is modified to store the new catalog tuple OID.
*
* NOTE: only pre-cooked expressions will be passed this way, which is to
* say expressions inherited from an existing relation. Newly parsed
* expressions can be added later, by direct calls to StoreAttrDefault
* and StoreRelCheck (see AddRelationNewConstraints()).
*/
static void
StoreConstraints(Relation rel, List *cooked_constraints, bool is_internal)
{
int numchecks = 0;
ListCell *lc;
if (cooked_constraints == NIL)
return; /* nothing to do */
/*
* Deparsing of constraint expressions will fail unless the just-created
* pg_attribute tuples for this relation are made visible. So, bump the
* command counter. CAUTION: this will cause a relcache entry rebuild.
*/
CommandCounterIncrement();
foreach(lc, cooked_constraints)
{
CookedConstraint *con = (CookedConstraint *) lfirst(lc);
switch (con->contype)
{
case CONSTR_DEFAULT:
con->conoid = StoreAttrDefault(rel, con->attnum, con->expr,
is_internal, false);
break;
case CONSTR_CHECK:
con->conoid =
StoreRelCheck(rel, con->name, con->expr,
!con->skip_validation, con->is_local,
con->inhcount, con->is_no_inherit,
is_internal);
numchecks++;
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
(int) con->contype);
}
}
if (numchecks > 0)
SetRelationNumChecks(rel, numchecks);
}
/*
* AddRelationNewConstraints
*
* Add new column default expressions and/or constraint check expressions
* to an existing relation. This is defined to do both for efficiency in
* DefineRelation, but of course you can do just one or the other by passing
* empty lists.
*
* rel: relation to be modified
* newColDefaults: list of RawColumnDefault structures
* newConstraints: list of Constraint nodes
* allow_merge: true if check constraints may be merged with existing ones
* is_local: true if definition is local, false if it's inherited
* is_internal: true if result of some internal process, not a user request
*
* All entries in newColDefaults will be processed. Entries in newConstraints
* will be processed only if they are CONSTR_CHECK type.
*
* Returns a list of CookedConstraint nodes that shows the cooked form of
* the default and constraint expressions added to the relation.
*
* NB: caller should have opened rel with AccessExclusiveLock, and should
* hold that lock till end of transaction. Also, we assume the caller has
* done a CommandCounterIncrement if necessary to make the relation's catalog
* tuples visible.
*/
List *
AddRelationNewConstraints(Relation rel,
List *newColDefaults,
List *newConstraints,
bool allow_merge,
bool is_local,
bool is_internal,
const char *queryString)
{
List *cookedConstraints = NIL;
TupleDesc tupleDesc;
TupleConstr *oldconstr;
int numoldchecks;
ParseState *pstate;
RangeTblEntry *rte;
int numchecks;
List *checknames;
ListCell *cell;
Node *expr;
CookedConstraint *cooked;
/*
* Get info about existing constraints.
*/
tupleDesc = RelationGetDescr(rel);
oldconstr = tupleDesc->constr;
if (oldconstr)
numoldchecks = oldconstr->num_check;
else
numoldchecks = 0;
/*
* Create a dummy ParseState and insert the target relation as its sole
* rangetable entry. We need a ParseState for transformExpr.
*/
pstate = make_parsestate(NULL);
pstate->p_sourcetext = queryString;
rte = addRangeTableEntryForRelation(pstate,
rel,
AccessShareLock,
NULL,
false,
true);
addRTEtoQuery(pstate, rte, true, true, true);
/*
* Process column default expressions.
*/
foreach(cell, newColDefaults)
{
RawColumnDefault *colDef = (RawColumnDefault *) lfirst(cell);
Form_pg_attribute atp = TupleDescAttr(rel->rd_att, colDef->attnum - 1);
Oid defOid;
expr = cookDefault(pstate, colDef->raw_default,
atp->atttypid, atp->atttypmod,
NameStr(atp->attname),
atp->attgenerated);
/*
* If the expression is just a NULL constant, we do not bother to make
* an explicit pg_attrdef entry, since the default behavior is
* equivalent. This applies to column defaults, but not for
* generation expressions.
*
* Note a nonobvious property of this test: if the column is of a
* domain type, what we'll get is not a bare null Const but a
* CoerceToDomain expr, so we will not discard the default. This is
* critical because the column default needs to be retained to
* override any default that the domain might have.
*/
if (expr == NULL ||
(!colDef->generated &&
IsA(expr, Const) &&
castNode(Const, expr)->constisnull))
continue;
/* If the DEFAULT is volatile we cannot use a missing value */
if (colDef->missingMode && contain_volatile_functions((Node *) expr))
colDef->missingMode = false;
defOid = StoreAttrDefault(rel, colDef->attnum, expr, is_internal,
colDef->missingMode);
cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
cooked->contype = CONSTR_DEFAULT;
cooked->conoid = defOid;
cooked->name = NULL;
cooked->attnum = colDef->attnum;
cooked->expr = expr;
cooked->skip_validation = false;
cooked->is_local = is_local;
cooked->inhcount = is_local ? 0 : 1;
cooked->is_no_inherit = false;
cookedConstraints = lappend(cookedConstraints, cooked);
}
/*
* Process constraint expressions.
*/
numchecks = numoldchecks;
checknames = NIL;
foreach(cell, newConstraints)
{
Constraint *cdef = (Constraint *) lfirst(cell);
char *ccname;
Oid constrOid;
if (cdef->contype != CONSTR_CHECK)
continue;
if (cdef->raw_expr != NULL)
{
Assert(cdef->cooked_expr == NULL);
/*
* Transform raw parsetree to executable expression, and verify
* it's valid as a CHECK constraint.
*/
expr = cookConstraint(pstate, cdef->raw_expr,
RelationGetRelationName(rel));
}
else
{
Assert(cdef->cooked_expr != NULL);
/*
* Here, we assume the parser will only pass us valid CHECK
* expressions, so we do no particular checking.
*/
expr = stringToNode(cdef->cooked_expr);
}
/*
* Check name uniqueness, or generate a name if none was given.
*/
if (cdef->conname != NULL)
{
ListCell *cell2;
ccname = cdef->conname;
/* Check against other new constraints */
/* Needed because we don't do CommandCounterIncrement in loop */
foreach(cell2, checknames)
{
if (strcmp((char *) lfirst(cell2), ccname) == 0)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("check constraint \"%s\" already exists",
ccname)));
}
/* save name for future checks */
checknames = lappend(checknames, ccname);
/*
* Check against pre-existing constraints. If we are allowed to
* merge with an existing constraint, there's no more to do here.
* (We omit the duplicate constraint from the result, which is
* what ATAddCheckConstraint wants.)
*/
if (MergeWithExistingConstraint(rel, ccname, expr,
allow_merge, is_local,
cdef->initially_valid,
cdef->is_no_inherit))
continue;
}
else
{
/*
* When generating a name, we want to create "tab_col_check" for a
* column constraint and "tab_check" for a table constraint. We
* no longer have any info about the syntactic positioning of the
* constraint phrase, so we approximate this by seeing whether the
* expression references more than one column. (If the user
* played by the rules, the result is the same...)
*
* Note: pull_var_clause() doesn't descend into sublinks, but we
* eliminated those above; and anyway this only needs to be an
* approximate answer.
*/
List *vars;
char *colname;
vars = pull_var_clause(expr, 0);
/* eliminate duplicates */
vars = list_union(NIL, vars);
if (list_length(vars) == 1)
colname = get_attname(RelationGetRelid(rel),
((Var *) linitial(vars))->varattno,
true);
else
colname = NULL;
ccname = ChooseConstraintName(RelationGetRelationName(rel),
colname,
"check",
RelationGetNamespace(rel),
checknames);
/* save name for future checks */
checknames = lappend(checknames, ccname);
}
/*
* OK, store it.
*/
constrOid =
StoreRelCheck(rel, ccname, expr, cdef->initially_valid, is_local,
is_local ? 0 : 1, cdef->is_no_inherit, is_internal);
numchecks++;
cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
cooked->contype = CONSTR_CHECK;
cooked->conoid = constrOid;
cooked->name = ccname;
cooked->attnum = 0;
cooked->expr = expr;
cooked->skip_validation = cdef->skip_validation;
cooked->is_local = is_local;
cooked->inhcount = is_local ? 0 : 1;
cooked->is_no_inherit = cdef->is_no_inherit;
cookedConstraints = lappend(cookedConstraints, cooked);
}
/*
* Update the count of constraints in the relation's pg_class tuple. We do
* this even if there was no change, in order to ensure that an SI update
* message is sent out for the pg_class tuple, which will force other
* backends to rebuild their relcache entries for the rel. (This is
* critical if we added defaults but not constraints.)
*/
SetRelationNumChecks(rel, numchecks);
return cookedConstraints;
}
/*
* Check for a pre-existing check constraint that conflicts with a proposed
* new one, and either adjust its conislocal/coninhcount settings or throw
* error as needed.
*
* Returns true if merged (constraint is a duplicate), or false if it's
* got a so-far-unique name, or throws error if conflict.
*
* XXX See MergeConstraintsIntoExisting too if you change this code.
*/
static bool
MergeWithExistingConstraint(Relation rel, const char *ccname, Node *expr,
bool allow_merge, bool is_local,
bool is_initially_valid,
bool is_no_inherit)
{
bool found;
Relation conDesc;
SysScanDesc conscan;
ScanKeyData skey[3];
HeapTuple tup;
/* Search for a pg_constraint entry with same name and relation */
conDesc = table_open(ConstraintRelationId, RowExclusiveLock);
found = false;
ScanKeyInit(&skey[0],
Anum_pg_constraint_conrelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(rel)));
ScanKeyInit(&skey[1],
Anum_pg_constraint_contypid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(InvalidOid));
ScanKeyInit(&skey[2],
Anum_pg_constraint_conname,
BTEqualStrategyNumber, F_NAMEEQ,
CStringGetDatum(ccname));
conscan = systable_beginscan(conDesc, ConstraintRelidTypidNameIndexId, true,
NULL, 3, skey);
/* There can be at most one matching row */
if (HeapTupleIsValid(tup = systable_getnext(conscan)))
{
Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tup);
/* Found it. Conflicts if not identical check constraint */
if (con->contype == CONSTRAINT_CHECK)
{
Datum val;
bool isnull;
val = fastgetattr(tup,
Anum_pg_constraint_conbin,
conDesc->rd_att, &isnull);
if (isnull)
elog(ERROR, "null conbin for rel %s",
RelationGetRelationName(rel));
if (equal(expr, stringToNode(TextDatumGetCString(val))))
found = true;
}
/*
* If the existing constraint is purely inherited (no local
* definition) then interpret addition of a local constraint as a
* legal merge. This allows ALTER ADD CONSTRAINT on parent and child
* tables to be given in either order with same end state. However if
* the relation is a partition, all inherited constraints are always
* non-local, including those that were merged.
*/
if (is_local && !con->conislocal && !rel->rd_rel->relispartition)
allow_merge = true;
if (!found || !allow_merge)
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_OBJECT),
errmsg("constraint \"%s\" for relation \"%s\" already exists",
ccname, RelationGetRelationName(rel))));
/* If the child constraint is "no inherit" then cannot merge */
if (con->connoinherit)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("constraint \"%s\" conflicts with non-inherited constraint on relation \"%s\"",
ccname, RelationGetRelationName(rel))));
/*
* Must not change an existing inherited constraint to "no inherit"
* status. That's because inherited constraints should be able to
* propagate to lower-level children.
*/
if (con->coninhcount > 0 && is_no_inherit)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("constraint \"%s\" conflicts with inherited constraint on relation \"%s\"",
ccname, RelationGetRelationName(rel))));
/*
* If the child constraint is "not valid" then cannot merge with a
* valid parent constraint.
*/
if (is_initially_valid && !con->convalidated)
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("constraint \"%s\" conflicts with NOT VALID constraint on relation \"%s\"",
ccname, RelationGetRelationName(rel))));
/* OK to update the tuple */
ereport(NOTICE,
(errmsg("merging constraint \"%s\" with inherited definition",
ccname)));
tup = heap_copytuple(tup);
con = (Form_pg_constraint) GETSTRUCT(tup);
/*
* In case of partitions, an inherited constraint must be inherited
* only once since it cannot have multiple parents and it is never
* considered local.
*/
if (rel->rd_rel->relispartition)
{
con->coninhcount = 1;
con->conislocal = false;
}
else
{
if (is_local)
con->conislocal = true;
else
con->coninhcount++;
}
if (is_no_inherit)
{
Assert(is_local);
con->connoinherit = true;
}
CatalogTupleUpdate(conDesc, &tup->t_self, tup);
}
systable_endscan(conscan);
table_close(conDesc, RowExclusiveLock);
return found;
}
/*
* Update the count of constraints in the relation's pg_class tuple.
*
* Caller had better hold exclusive lock on the relation.
*
* An important side effect is that a SI update message will be sent out for
* the pg_class tuple, which will force other backends to rebuild their
* relcache entries for the rel. Also, this backend will rebuild its
* own relcache entry at the next CommandCounterIncrement.
*/
static void
SetRelationNumChecks(Relation rel, int numchecks)
{
Relation relrel;
HeapTuple reltup;
Form_pg_class relStruct;
relrel = table_open(RelationRelationId, RowExclusiveLock);
reltup = SearchSysCacheCopy1(RELOID,
ObjectIdGetDatum(RelationGetRelid(rel)));
if (!HeapTupleIsValid(reltup))
elog(ERROR, "cache lookup failed for relation %u",
RelationGetRelid(rel));
relStruct = (Form_pg_class) GETSTRUCT(reltup);
if (relStruct->relchecks != numchecks)
{
relStruct->relchecks = numchecks;
CatalogTupleUpdate(relrel, &reltup->t_self, reltup);
}
else
{
/* Skip the disk update, but force relcache inval anyway */
CacheInvalidateRelcache(rel);
}
heap_freetuple(reltup);
table_close(relrel, RowExclusiveLock);
}
/*
* Check for references to generated columns
*/
static bool
check_nested_generated_walker(Node *node, void *context)
{
ParseState *pstate = context;
if (node == NULL)
return false;
else if (IsA(node, Var))
{
Var *var = (Var *) node;
Oid relid;
AttrNumber attnum;
relid = rt_fetch(var->varno, pstate->p_rtable)->relid;
attnum = var->varattno;
if (OidIsValid(relid) && AttributeNumberIsValid(attnum) && get_attgenerated(relid, attnum))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("cannot use generated column \"%s\" in column generation expression",
get_attname(relid, attnum, false)),
errdetail("A generated column cannot reference another generated column."),
parser_errposition(pstate, var->location)));
return false;
}
else
return expression_tree_walker(node, check_nested_generated_walker,
(void *) context);
}
static void
check_nested_generated(ParseState *pstate, Node *node)
{
check_nested_generated_walker(node, pstate);
}
/*
* Take a raw default and convert it to a cooked format ready for
* storage.
*
* Parse state should be set up to recognize any vars that might appear
* in the expression. (Even though we plan to reject vars, it's more
* user-friendly to give the correct error message than "unknown var".)
*
* If atttypid is not InvalidOid, coerce the expression to the specified
* type (and typmod atttypmod). attname is only needed in this case:
* it is used in the error message, if any.
*/
Node *
cookDefault(ParseState *pstate,
Node *raw_default,
Oid atttypid,
int32 atttypmod,
const char *attname,
char attgenerated)
{
Node *expr;
Assert(raw_default != NULL);
/*
* Transform raw parsetree to executable expression.
*/
expr = transformExpr(pstate, raw_default, attgenerated ? EXPR_KIND_GENERATED_COLUMN : EXPR_KIND_COLUMN_DEFAULT);
if (attgenerated)
{
check_nested_generated(pstate, expr);
if (contain_mutable_functions(expr))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("generation expression is not immutable")));
}
else
{
/*
* For a default expression, transformExpr() should have rejected
* column references.
*/
Assert(!contain_var_clause(expr));
}
/*
* Coerce the expression to the correct type and typmod, if given. This
* should match the parser's processing of non-defaulted expressions ---
* see transformAssignedExpr().
*/
if (OidIsValid(atttypid))
{
Oid type_id = exprType(expr);
expr = coerce_to_target_type(pstate, expr, type_id,
atttypid, atttypmod,
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST,
-1);
if (expr == NULL)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("column \"%s\" is of type %s"
" but default expression is of type %s",
attname,
format_type_be(atttypid),
format_type_be(type_id)),
errhint("You will need to rewrite or cast the expression.")));
}
/*
* Finally, take care of collations in the finished expression.
*/
assign_expr_collations(pstate, expr);
return expr;
}
/*
* Take a raw CHECK constraint expression and convert it to a cooked format
* ready for storage.
*
* Parse state must be set up to recognize any vars that might appear
* in the expression.
*/
static Node *
cookConstraint(ParseState *pstate,
Node *raw_constraint,
char *relname)
{
Node *expr;
/*
* Transform raw parsetree to executable expression.
*/
expr = transformExpr(pstate, raw_constraint, EXPR_KIND_CHECK_CONSTRAINT);
/*
* Make sure it yields a boolean result.
*/
expr = coerce_to_boolean(pstate, expr, "CHECK");
/*
* Take care of collations.
*/
assign_expr_collations(pstate, expr);
/*
* Make sure no outside relations are referred to (this is probably dead
* code now that add_missing_from is history).
*/
if (list_length(pstate->p_rtable) != 1)
ereport(ERROR,
(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
errmsg("only table \"%s\" can be referenced in check constraint",
relname)));
return expr;
}
/*
* RemoveStatistics --- remove entries in pg_statistic for a rel or column
*
* If attnum is zero, remove all entries for rel; else remove only the one(s)
* for that column.
*/
void
RemoveStatistics(Oid relid, AttrNumber attnum)
{
Relation pgstatistic;
SysScanDesc scan;
ScanKeyData key[2];
int nkeys;
HeapTuple tuple;
pgstatistic = table_open(StatisticRelationId, RowExclusiveLock);
ScanKeyInit(&key[0],
Anum_pg_statistic_starelid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
if (attnum == 0)
nkeys = 1;
else
{
ScanKeyInit(&key[1],
Anum_pg_statistic_staattnum,
BTEqualStrategyNumber, F_INT2EQ,
Int16GetDatum(attnum));
nkeys = 2;
}
scan = systable_beginscan(pgstatistic, StatisticRelidAttnumInhIndexId, true,
NULL, nkeys, key);
/* we must loop even when attnum != 0, in case of inherited stats */
while (HeapTupleIsValid(tuple = systable_getnext(scan)))
CatalogTupleDelete(pgstatistic, &tuple->t_self);
systable_endscan(scan);
table_close(pgstatistic, RowExclusiveLock);
}
/*
* RelationTruncateIndexes - truncate all indexes associated
* with the heap relation to zero tuples.
*
* The routine will truncate and then reconstruct the indexes on
* the specified relation. Caller must hold exclusive lock on rel.
*/
static void
RelationTruncateIndexes(Relation heapRelation)
{
ListCell *indlist;
/* Ask the relcache to produce a list of the indexes of the rel */
foreach(indlist, RelationGetIndexList(heapRelation))
{
Oid indexId = lfirst_oid(indlist);
Relation currentIndex;
IndexInfo *indexInfo;
/* Open the index relation; use exclusive lock, just to be sure */
currentIndex = index_open(indexId, AccessExclusiveLock);
/* Fetch info needed for index_build */
indexInfo = BuildIndexInfo(currentIndex);
/*
* Now truncate the actual file (and discard buffers).
*/
RelationTruncate(currentIndex, 0);
/* Initialize the index and rebuild */
/* Note: we do not need to re-establish pkey setting */
index_build(heapRelation, currentIndex, indexInfo, true, false);
/* We're done with this index */
index_close(currentIndex, NoLock);
}
}
/*
* heap_truncate
*
* This routine deletes all data within all the specified relations.
*
* This is not transaction-safe! There is another, transaction-safe
* implementation in commands/tablecmds.c. We now use this only for
* ON COMMIT truncation of temporary tables, where it doesn't matter.
*/
void
heap_truncate(List *relids)
{
List *relations = NIL;
ListCell *cell;
/* Open relations for processing, and grab exclusive access on each */
foreach(cell, relids)
{
Oid rid = lfirst_oid(cell);
Relation rel;
rel = table_open(rid, AccessExclusiveLock);
relations = lappend(relations, rel);
}
/* Don't allow truncate on tables that are referenced by foreign keys */
heap_truncate_check_FKs(relations, true);
/* OK to do it */
foreach(cell, relations)
{
Relation rel = lfirst(cell);
/* Truncate the relation */
heap_truncate_one_rel(rel);
/* Close the relation, but keep exclusive lock on it until commit */
table_close(rel, NoLock);
}
}
/*
* heap_truncate_one_rel
*
* This routine deletes all data within the specified relation.
*
* This is not transaction-safe, because the truncation is done immediately
* and cannot be rolled back later. Caller is responsible for having
* checked permissions etc, and must have obtained AccessExclusiveLock.
*/
void
heap_truncate_one_rel(Relation rel)
{
Oid toastrelid;
/*
* Truncate the relation. Partitioned tables have no storage, so there is
* nothing to do for them here.
*/
if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
return;
/* Truncate the underlying relation */
table_relation_nontransactional_truncate(rel);
/* If the relation has indexes, truncate the indexes too */
RelationTruncateIndexes(rel);
/* If there is a toast table, truncate that too */
toastrelid = rel->rd_rel->reltoastrelid;
if (OidIsValid(toastrelid))
{
Relation toastrel = table_open(toastrelid, AccessExclusiveLock);
table_relation_nontransactional_truncate(toastrel);
RelationTruncateIndexes(toastrel);
/* keep the lock... */
table_close(toastrel, NoLock);
}
}
/*
* heap_truncate_check_FKs
* Check for foreign keys referencing a list of relations that
* are to be truncated, and raise error if there are any
*
* We disallow such FKs (except self-referential ones) since the whole point
* of TRUNCATE is to not scan the individual rows to be thrown away.
*
* This is split out so it can be shared by both implementations of truncate.
* Caller should already hold a suitable lock on the relations.
*
* tempTables is only used to select an appropriate error message.
*/
void
heap_truncate_check_FKs(List *relations, bool tempTables)
{
List *oids = NIL;
List *dependents;
ListCell *cell;
/*
* Build a list of OIDs of the interesting relations.
*
* If a relation has no triggers, then it can neither have FKs nor be
* referenced by a FK from another table, so we can ignore it. For
* partitioned tables, FKs have no triggers, so we must include them
* anyway.
*/
foreach(cell, relations)
{
Relation rel = lfirst(cell);
if (rel->rd_rel->relhastriggers ||
rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
oids = lappend_oid(oids, RelationGetRelid(rel));
}
/*
* Fast path: if no relation has triggers, none has FKs either.
*/
if (oids == NIL)
return;
/*
* Otherwise, must scan pg_constraint. We make one pass with all the
* relations considered; if this finds nothing, then all is well.
*/
dependents = heap_truncate_find_FKs(oids);
if (dependents == NIL)
return;
/*
* Otherwise we repeat the scan once per relation to identify a particular
* pair of relations to complain about. This is pretty slow, but
* performance shouldn't matter much in a failure path. The reason for
* doing things this way is to ensure that the message produced is not
* dependent on chance row locations within pg_constraint.
*/
foreach(cell, oids)
{
Oid relid = lfirst_oid(cell);
ListCell *cell2;
dependents = heap_truncate_find_FKs(list_make1_oid(relid));
foreach(cell2, dependents)
{
Oid relid2 = lfirst_oid(cell2);
if (!list_member_oid(oids, relid2))
{
char *relname = get_rel_name(relid);
char *relname2 = get_rel_name(relid2);
if (tempTables)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("unsupported ON COMMIT and foreign key combination"),
errdetail("Table \"%s\" references \"%s\", but they do not have the same ON COMMIT setting.",
relname2, relname)));
else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot truncate a table referenced in a foreign key constraint"),
errdetail("Table \"%s\" references \"%s\".",
relname2, relname),
errhint("Truncate table \"%s\" at the same time, "
"or use TRUNCATE ... CASCADE.",
relname2)));
}
}
}
}
/*
* heap_truncate_find_FKs
* Find relations having foreign keys referencing any of the given rels
*
* Input and result are both lists of relation OIDs. The result contains
* no duplicates, does *not* include any rels that were already in the input
* list, and is sorted in OID order. (The last property is enforced mainly
* to guarantee consistent behavior in the regression tests; we don't want
* behavior to change depending on chance locations of rows in pg_constraint.)
*
* Note: caller should already have appropriate lock on all rels mentioned
* in relationIds. Since adding or dropping an FK requires exclusive lock
* on both rels, this ensures that the answer will be stable.
*/
List *
heap_truncate_find_FKs(List *relationIds)
{
List *result = NIL;
Relation fkeyRel;
SysScanDesc fkeyScan;
HeapTuple tuple;
/*
* Must scan pg_constraint. Right now, it is a seqscan because there is
* no available index on confrelid.
*/
fkeyRel = table_open(ConstraintRelationId, AccessShareLock);
fkeyScan = systable_beginscan(fkeyRel, InvalidOid, false,
NULL, 0, NULL);
while (HeapTupleIsValid(tuple = systable_getnext(fkeyScan)))
{
Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
/* Not a foreign key */
if (con->contype != CONSTRAINT_FOREIGN)
continue;
/* Not referencing one of our list of tables */
if (!list_member_oid(relationIds, con->confrelid))
continue;
/* Add referencer to result, unless present in input list */
if (!list_member_oid(relationIds, con->conrelid))
result = lappend_oid(result, con->conrelid);
}
systable_endscan(fkeyScan);
table_close(fkeyRel, AccessShareLock);
/* Now sort and de-duplicate the result list */
list_sort(result, list_oid_cmp);
list_deduplicate_oid(result);
return result;
}
/*
* StorePartitionKey
* Store information about the partition key rel into the catalog
*/
void
StorePartitionKey(Relation rel,
char strategy,
int16 partnatts,
AttrNumber *partattrs,
List *partexprs,
Oid *partopclass,
Oid *partcollation)
{
int i;
int2vector *partattrs_vec;
oidvector *partopclass_vec;
oidvector *partcollation_vec;
Datum partexprDatum;
Relation pg_partitioned_table;
HeapTuple tuple;
Datum values[Natts_pg_partitioned_table];
bool nulls[Natts_pg_partitioned_table];
ObjectAddress myself;
ObjectAddress referenced;
Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
/* Copy the partition attribute numbers, opclass OIDs into arrays */
partattrs_vec = buildint2vector(partattrs, partnatts);
partopclass_vec = buildoidvector(partopclass, partnatts);
partcollation_vec = buildoidvector(partcollation, partnatts);
/* Convert the expressions (if any) to a text datum */
if (partexprs)
{
char *exprString;
exprString = nodeToString(partexprs);
partexprDatum = CStringGetTextDatum(exprString);
pfree(exprString);
}
else
partexprDatum = (Datum) 0;
pg_partitioned_table = table_open(PartitionedRelationId, RowExclusiveLock);
MemSet(nulls, false, sizeof(nulls));
/* Only this can ever be NULL */
if (!partexprDatum)
nulls[Anum_pg_partitioned_table_partexprs - 1] = true;
values[Anum_pg_partitioned_table_partrelid - 1] = ObjectIdGetDatum(RelationGetRelid(rel));
values[Anum_pg_partitioned_table_partstrat - 1] = CharGetDatum(strategy);
values[Anum_pg_partitioned_table_partnatts - 1] = Int16GetDatum(partnatts);
values[Anum_pg_partitioned_table_partdefid - 1] = ObjectIdGetDatum(InvalidOid);
values[Anum_pg_partitioned_table_partattrs - 1] = PointerGetDatum(partattrs_vec);
values[Anum_pg_partitioned_table_partclass - 1] = PointerGetDatum(partopclass_vec);
values[Anum_pg_partitioned_table_partcollation - 1] = PointerGetDatum(partcollation_vec);
values[Anum_pg_partitioned_table_partexprs - 1] = partexprDatum;
tuple = heap_form_tuple(RelationGetDescr(pg_partitioned_table), values, nulls);
CatalogTupleInsert(pg_partitioned_table, tuple);
table_close(pg_partitioned_table, RowExclusiveLock);
/* Mark this relation as dependent on a few things as follows */
myself.classId = RelationRelationId;
myself.objectId = RelationGetRelid(rel);
myself.objectSubId = 0;
/* Operator class and collation per key column */
for (i = 0; i < partnatts; i++)
{
referenced.classId = OperatorClassRelationId;
referenced.objectId = partopclass[i];
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
/* The default collation is pinned, so don't bother recording it */
if (OidIsValid(partcollation[i]) &&
partcollation[i] != DEFAULT_COLLATION_OID)
{
referenced.classId = CollationRelationId;
referenced.objectId = partcollation[i];
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
}
/*
* Anything mentioned in the expressions. We must ignore the column
* references, which will depend on the table itself; there is no separate
* partition key object.
*/
if (partexprs)
recordDependencyOnSingleRelExpr(&myself,
(Node *) partexprs,
RelationGetRelid(rel),
DEPENDENCY_NORMAL,
DEPENDENCY_AUTO, true);
/*
* We must invalidate the relcache so that the next
* CommandCounterIncrement() will cause the same to be rebuilt using the
* information in just created catalog entry.
*/
CacheInvalidateRelcache(rel);
}
/*
* RemovePartitionKeyByRelId
* Remove pg_partitioned_table entry for a relation
*/
void
RemovePartitionKeyByRelId(Oid relid)
{
Relation rel;
HeapTuple tuple;
rel = table_open(PartitionedRelationId, RowExclusiveLock);
tuple = SearchSysCache1(PARTRELID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for partition key of relation %u",
relid);
CatalogTupleDelete(rel, &tuple->t_self);
ReleaseSysCache(tuple);
table_close(rel, RowExclusiveLock);
}
/*
* StorePartitionBound
* Update pg_class tuple of rel to store the partition bound and set
* relispartition to true
*
* If this is the default partition, also update the default partition OID in
* pg_partitioned_table.
*
* Also, invalidate the parent's relcache, so that the next rebuild will load
* the new partition's info into its partition descriptor. If there is a
* default partition, we must invalidate its relcache entry as well.
*/
void
StorePartitionBound(Relation rel, Relation parent, PartitionBoundSpec *bound)
{
Relation classRel;
HeapTuple tuple,
newtuple;
Datum new_val[Natts_pg_class];
bool new_null[Natts_pg_class],
new_repl[Natts_pg_class];
Oid defaultPartOid;
/* Update pg_class tuple */
classRel = table_open(RelationRelationId, RowExclusiveLock);
tuple = SearchSysCacheCopy1(RELOID,
ObjectIdGetDatum(RelationGetRelid(rel)));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for relation %u",
RelationGetRelid(rel));
#ifdef USE_ASSERT_CHECKING
{
Form_pg_class classForm;
bool isnull;
classForm = (Form_pg_class) GETSTRUCT(tuple);
Assert(!classForm->relispartition);
(void) SysCacheGetAttr(RELOID, tuple, Anum_pg_class_relpartbound,
&isnull);
Assert(isnull);
}
#endif
/* Fill in relpartbound value */
memset(new_val, 0, sizeof(new_val));
memset(new_null, false, sizeof(new_null));
memset(new_repl, false, sizeof(new_repl));
new_val[Anum_pg_class_relpartbound - 1] = CStringGetTextDatum(nodeToString(bound));
new_null[Anum_pg_class_relpartbound - 1] = false;
new_repl[Anum_pg_class_relpartbound - 1] = true;
newtuple = heap_modify_tuple(tuple, RelationGetDescr(classRel),
new_val, new_null, new_repl);
/* Also set the flag */
((Form_pg_class) GETSTRUCT(newtuple))->relispartition = true;
CatalogTupleUpdate(classRel, &newtuple->t_self, newtuple);
heap_freetuple(newtuple);
table_close(classRel, RowExclusiveLock);
/*
* If we're storing bounds for the default partition, update
* pg_partitioned_table too.
*/
if (bound->is_default)
update_default_partition_oid(RelationGetRelid(parent),
RelationGetRelid(rel));
/* Make these updates visible */
CommandCounterIncrement();
/*
* The partition constraint for the default partition depends on the
* partition bounds of every other partition, so we must invalidate the
* relcache entry for that partition every time a partition is added or
* removed.
*/
defaultPartOid = get_default_oid_from_partdesc(RelationGetPartitionDesc(parent));
if (OidIsValid(defaultPartOid))
CacheInvalidateRelcacheByRelid(defaultPartOid);
CacheInvalidateRelcache(parent);
}
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