mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-08-22 07:53:22 +02:00
381 lines
11 KiB
C
381 lines
11 KiB
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* toasting.c
|
|
* This file contains routines to support creation of toast tables
|
|
*
|
|
*
|
|
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
|
|
* Portions Copyright (c) 1994, Regents of the University of California
|
|
*
|
|
* IDENTIFICATION
|
|
* $PostgreSQL: pgsql/src/backend/catalog/toasting.c,v 1.26 2010/01/02 16:57:36 momjian Exp $
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
#include "postgres.h"
|
|
|
|
#include "access/heapam.h"
|
|
#include "access/tuptoaster.h"
|
|
#include "access/xact.h"
|
|
#include "catalog/dependency.h"
|
|
#include "catalog/heap.h"
|
|
#include "catalog/index.h"
|
|
#include "catalog/indexing.h"
|
|
#include "catalog/namespace.h"
|
|
#include "catalog/pg_namespace.h"
|
|
#include "catalog/pg_opclass.h"
|
|
#include "catalog/pg_type.h"
|
|
#include "catalog/toasting.h"
|
|
#include "miscadmin.h"
|
|
#include "nodes/makefuncs.h"
|
|
#include "utils/builtins.h"
|
|
#include "utils/syscache.h"
|
|
|
|
Oid binary_upgrade_next_pg_type_toast_oid = InvalidOid;
|
|
|
|
static bool create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid,
|
|
Datum reloptions, bool force);
|
|
static bool needs_toast_table(Relation rel);
|
|
|
|
|
|
/*
|
|
* AlterTableCreateToastTable
|
|
* If the table needs a toast table, and doesn't already have one,
|
|
* then create a toast table for it. (With the force option, make
|
|
* a toast table even if it appears unnecessary.)
|
|
*
|
|
* The caller can also specify the OID to be used for the toast table.
|
|
* Usually, toastOid should be InvalidOid to allow a free OID to be assigned.
|
|
* (This option, as well as the force option, is not used by core Postgres,
|
|
* but is provided to support pg_migrator.)
|
|
*
|
|
* reloptions for the toast table can be passed, too. Pass (Datum) 0
|
|
* for default reloptions.
|
|
*
|
|
* We expect the caller to have verified that the relation is a table and have
|
|
* already done any necessary permission checks. Callers expect this function
|
|
* to end with CommandCounterIncrement if it makes any changes.
|
|
*/
|
|
void
|
|
AlterTableCreateToastTable(Oid relOid, Oid toastOid,
|
|
Datum reloptions, bool force)
|
|
{
|
|
Relation rel;
|
|
|
|
/*
|
|
* Grab an exclusive lock on the target table, which we will NOT release
|
|
* until end of transaction. (This is probably redundant in all present
|
|
* uses...)
|
|
*/
|
|
rel = heap_open(relOid, AccessExclusiveLock);
|
|
|
|
/* create_toast_table does all the work */
|
|
(void) create_toast_table(rel, toastOid, InvalidOid, reloptions, force);
|
|
|
|
heap_close(rel, NoLock);
|
|
}
|
|
|
|
/*
|
|
* Create a toast table during bootstrap
|
|
*
|
|
* Here we need to prespecify the OIDs of the toast table and its index
|
|
*/
|
|
void
|
|
BootstrapToastTable(char *relName, Oid toastOid, Oid toastIndexOid)
|
|
{
|
|
Relation rel;
|
|
|
|
rel = heap_openrv(makeRangeVar(NULL, relName, -1), AccessExclusiveLock);
|
|
|
|
/* Note: during bootstrap may see uncataloged relation */
|
|
if (rel->rd_rel->relkind != RELKIND_RELATION &&
|
|
rel->rd_rel->relkind != RELKIND_UNCATALOGED)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("\"%s\" is not a table",
|
|
relName)));
|
|
|
|
/* create_toast_table does all the work */
|
|
if (!create_toast_table(rel, toastOid, toastIndexOid, (Datum) 0, false))
|
|
elog(ERROR, "\"%s\" does not require a toast table",
|
|
relName);
|
|
|
|
heap_close(rel, NoLock);
|
|
}
|
|
|
|
|
|
/*
|
|
* create_toast_table --- internal workhorse
|
|
*
|
|
* rel is already opened and exclusive-locked
|
|
* toastOid and toastIndexOid are normally InvalidOid, but
|
|
* either or both can be nonzero to specify caller-assigned OIDs
|
|
*/
|
|
static bool
|
|
create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid,
|
|
Datum reloptions, bool force)
|
|
{
|
|
Oid relOid = RelationGetRelid(rel);
|
|
HeapTuple reltup;
|
|
TupleDesc tupdesc;
|
|
bool shared_relation;
|
|
Relation class_rel;
|
|
Oid toast_relid;
|
|
Oid toast_idxid;
|
|
Oid toast_typid = InvalidOid;
|
|
Oid namespaceid;
|
|
char toast_relname[NAMEDATALEN];
|
|
char toast_idxname[NAMEDATALEN];
|
|
IndexInfo *indexInfo;
|
|
Oid classObjectId[2];
|
|
int16 coloptions[2];
|
|
ObjectAddress baseobject,
|
|
toastobject;
|
|
|
|
/*
|
|
* Toast table is shared if and only if its parent is.
|
|
*
|
|
* We cannot allow toasting a shared relation after initdb (because
|
|
* there's no way to mark it toasted in other databases' pg_class).
|
|
*/
|
|
shared_relation = rel->rd_rel->relisshared;
|
|
if (shared_relation && !IsBootstrapProcessingMode())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
|
|
errmsg("shared tables cannot be toasted after initdb")));
|
|
|
|
/*
|
|
* Is it already toasted?
|
|
*/
|
|
if (rel->rd_rel->reltoastrelid != InvalidOid)
|
|
return false;
|
|
|
|
/*
|
|
* Check to see whether the table actually needs a TOAST table.
|
|
*
|
|
* Caller can optionally override this check. (Note: at present no
|
|
* callers in core Postgres do so, but this option is needed by
|
|
* pg_migrator.)
|
|
*/
|
|
if (!force && !needs_toast_table(rel))
|
|
return false;
|
|
|
|
/*
|
|
* Create the toast table and its index
|
|
*/
|
|
snprintf(toast_relname, sizeof(toast_relname),
|
|
"pg_toast_%u", relOid);
|
|
snprintf(toast_idxname, sizeof(toast_idxname),
|
|
"pg_toast_%u_index", relOid);
|
|
|
|
/* this is pretty painful... need a tuple descriptor */
|
|
tupdesc = CreateTemplateTupleDesc(3, false);
|
|
TupleDescInitEntry(tupdesc, (AttrNumber) 1,
|
|
"chunk_id",
|
|
OIDOID,
|
|
-1, 0);
|
|
TupleDescInitEntry(tupdesc, (AttrNumber) 2,
|
|
"chunk_seq",
|
|
INT4OID,
|
|
-1, 0);
|
|
TupleDescInitEntry(tupdesc, (AttrNumber) 3,
|
|
"chunk_data",
|
|
BYTEAOID,
|
|
-1, 0);
|
|
|
|
/*
|
|
* Ensure that the toast table doesn't itself get toasted, or we'll be
|
|
* toast :-(. This is essential for chunk_data because type bytea is
|
|
* toastable; hit the other two just to be sure.
|
|
*/
|
|
tupdesc->attrs[0]->attstorage = 'p';
|
|
tupdesc->attrs[1]->attstorage = 'p';
|
|
tupdesc->attrs[2]->attstorage = 'p';
|
|
|
|
/*
|
|
* Toast tables for regular relations go in pg_toast; those for temp
|
|
* relations go into the per-backend temp-toast-table namespace.
|
|
*/
|
|
if (rel->rd_islocaltemp)
|
|
namespaceid = GetTempToastNamespace();
|
|
else
|
|
namespaceid = PG_TOAST_NAMESPACE;
|
|
|
|
if (OidIsValid(binary_upgrade_next_pg_type_toast_oid))
|
|
{
|
|
toast_typid = binary_upgrade_next_pg_type_toast_oid;
|
|
binary_upgrade_next_pg_type_toast_oid = InvalidOid;
|
|
}
|
|
|
|
toast_relid = heap_create_with_catalog(toast_relname,
|
|
namespaceid,
|
|
rel->rd_rel->reltablespace,
|
|
toastOid,
|
|
toast_typid,
|
|
rel->rd_rel->relowner,
|
|
tupdesc,
|
|
NIL,
|
|
RELKIND_TOASTVALUE,
|
|
shared_relation,
|
|
true,
|
|
0,
|
|
ONCOMMIT_NOOP,
|
|
reloptions,
|
|
false,
|
|
true);
|
|
|
|
/* make the toast relation visible, else index creation will fail */
|
|
CommandCounterIncrement();
|
|
|
|
/*
|
|
* Create unique index on chunk_id, chunk_seq.
|
|
*
|
|
* NOTE: the normal TOAST access routines could actually function with a
|
|
* single-column index on chunk_id only. However, the slice access
|
|
* routines use both columns for faster access to an individual chunk. In
|
|
* addition, we want it to be unique as a check against the possibility of
|
|
* duplicate TOAST chunk OIDs. The index might also be a little more
|
|
* efficient this way, since btree isn't all that happy with large numbers
|
|
* of equal keys.
|
|
*/
|
|
|
|
indexInfo = makeNode(IndexInfo);
|
|
indexInfo->ii_NumIndexAttrs = 2;
|
|
indexInfo->ii_KeyAttrNumbers[0] = 1;
|
|
indexInfo->ii_KeyAttrNumbers[1] = 2;
|
|
indexInfo->ii_Expressions = NIL;
|
|
indexInfo->ii_ExpressionsState = NIL;
|
|
indexInfo->ii_Predicate = NIL;
|
|
indexInfo->ii_PredicateState = NIL;
|
|
indexInfo->ii_ExclusionOps = NULL;
|
|
indexInfo->ii_ExclusionProcs = NULL;
|
|
indexInfo->ii_ExclusionStrats = NULL;
|
|
indexInfo->ii_Unique = true;
|
|
indexInfo->ii_ReadyForInserts = true;
|
|
indexInfo->ii_Concurrent = false;
|
|
indexInfo->ii_BrokenHotChain = false;
|
|
|
|
classObjectId[0] = OID_BTREE_OPS_OID;
|
|
classObjectId[1] = INT4_BTREE_OPS_OID;
|
|
|
|
coloptions[0] = 0;
|
|
coloptions[1] = 0;
|
|
|
|
toast_idxid = index_create(toast_relid, toast_idxname, toastIndexOid,
|
|
indexInfo,
|
|
list_make2("chunk_id", "chunk_seq"),
|
|
BTREE_AM_OID,
|
|
rel->rd_rel->reltablespace,
|
|
classObjectId, coloptions, (Datum) 0,
|
|
true, false, false, false,
|
|
true, false, false);
|
|
|
|
/*
|
|
* Store the toast table's OID in the parent relation's pg_class row
|
|
*/
|
|
class_rel = heap_open(RelationRelationId, RowExclusiveLock);
|
|
|
|
reltup = SearchSysCacheCopy(RELOID,
|
|
ObjectIdGetDatum(relOid),
|
|
0, 0, 0);
|
|
if (!HeapTupleIsValid(reltup))
|
|
elog(ERROR, "cache lookup failed for relation %u", relOid);
|
|
|
|
((Form_pg_class) GETSTRUCT(reltup))->reltoastrelid = toast_relid;
|
|
|
|
if (!IsBootstrapProcessingMode())
|
|
{
|
|
/* normal case, use a transactional update */
|
|
simple_heap_update(class_rel, &reltup->t_self, reltup);
|
|
|
|
/* Keep catalog indexes current */
|
|
CatalogUpdateIndexes(class_rel, reltup);
|
|
}
|
|
else
|
|
{
|
|
/* While bootstrapping, we cannot UPDATE, so overwrite in-place */
|
|
heap_inplace_update(class_rel, reltup);
|
|
}
|
|
|
|
heap_freetuple(reltup);
|
|
|
|
heap_close(class_rel, RowExclusiveLock);
|
|
|
|
/*
|
|
* Register dependency from the toast table to the master, so that the
|
|
* toast table will be deleted if the master is. Skip this in bootstrap
|
|
* mode.
|
|
*/
|
|
if (!IsBootstrapProcessingMode())
|
|
{
|
|
baseobject.classId = RelationRelationId;
|
|
baseobject.objectId = relOid;
|
|
baseobject.objectSubId = 0;
|
|
toastobject.classId = RelationRelationId;
|
|
toastobject.objectId = toast_relid;
|
|
toastobject.objectSubId = 0;
|
|
|
|
recordDependencyOn(&toastobject, &baseobject, DEPENDENCY_INTERNAL);
|
|
}
|
|
|
|
/*
|
|
* Make changes visible
|
|
*/
|
|
CommandCounterIncrement();
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Check to see whether the table needs a TOAST table. It does only if
|
|
* (1) there are any toastable attributes, and (2) the maximum length
|
|
* of a tuple could exceed TOAST_TUPLE_THRESHOLD. (We don't want to
|
|
* create a toast table for something like "f1 varchar(20)".)
|
|
*/
|
|
static bool
|
|
needs_toast_table(Relation rel)
|
|
{
|
|
int32 data_length = 0;
|
|
bool maxlength_unknown = false;
|
|
bool has_toastable_attrs = false;
|
|
TupleDesc tupdesc;
|
|
Form_pg_attribute *att;
|
|
int32 tuple_length;
|
|
int i;
|
|
|
|
tupdesc = rel->rd_att;
|
|
att = tupdesc->attrs;
|
|
|
|
for (i = 0; i < tupdesc->natts; i++)
|
|
{
|
|
if (att[i]->attisdropped)
|
|
continue;
|
|
data_length = att_align_nominal(data_length, att[i]->attalign);
|
|
if (att[i]->attlen > 0)
|
|
{
|
|
/* Fixed-length types are never toastable */
|
|
data_length += att[i]->attlen;
|
|
}
|
|
else
|
|
{
|
|
int32 maxlen = type_maximum_size(att[i]->atttypid,
|
|
att[i]->atttypmod);
|
|
|
|
if (maxlen < 0)
|
|
maxlength_unknown = true;
|
|
else
|
|
data_length += maxlen;
|
|
if (att[i]->attstorage != 'p')
|
|
has_toastable_attrs = true;
|
|
}
|
|
}
|
|
if (!has_toastable_attrs)
|
|
return false; /* nothing to toast? */
|
|
if (maxlength_unknown)
|
|
return true; /* any unlimited-length attrs? */
|
|
tuple_length = MAXALIGN(offsetof(HeapTupleHeaderData, t_bits) +
|
|
BITMAPLEN(tupdesc->natts)) +
|
|
MAXALIGN(data_length);
|
|
return (tuple_length > TOAST_TUPLE_THRESHOLD);
|
|
}
|