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postgresql/src/backend/catalog/index.c

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/*-------------------------------------------------------------------------
*
* index.c
* code to create and destroy POSTGRES index relations
*
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.215 2003/09/19 19:57:42 tgl Exp $
*
*
* INTERFACE ROUTINES
* index_create() - Create a cataloged index relation
* index_drop() - Removes index relation from catalogs
* BuildIndexInfo() - Prepare to insert index tuples
* FormIndexDatum() - Construct datum vector for one index tuple
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <unistd.h>
#include "access/genam.h"
#include "access/heapam.h"
#include "access/istrat.h"
#include "bootstrap/bootstrap.h"
#include "catalog/catalog.h"
#include "catalog/catname.h"
#include "catalog/dependency.h"
#include "catalog/heap.h"
#include "catalog/index.h"
#include "catalog/indexing.h"
#include "catalog/pg_constraint.h"
#include "catalog/pg_index.h"
#include "catalog/pg_opclass.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
#include "executor/executor.h"
#include "miscadmin.h"
#include "optimizer/clauses.h"
#include "optimizer/prep.h"
#include "parser/parse_expr.h"
#include "parser/parse_func.h"
#include "storage/sinval.h"
#include "storage/smgr.h"
#include "utils/builtins.h"
#include "utils/catcache.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/relcache.h"
#include "utils/syscache.h"
/*
* macros used in guessing how many tuples are on a page.
*/
#define AVG_ATTR_SIZE 8
#define NTUPLES_PER_PAGE(natts) \
((BLCKSZ - MAXALIGN(sizeof(PageHeaderData))) / \
((natts) * AVG_ATTR_SIZE + MAXALIGN(sizeof(HeapTupleHeaderData))))
/* non-export function prototypes */
static TupleDesc ConstructTupleDescriptor(Relation heapRelation,
IndexInfo *indexInfo,
Oid *classObjectId);
static void UpdateRelationRelation(Relation indexRelation);
static void InitializeAttributeOids(Relation indexRelation,
int numatts, Oid indexoid);
static void AppendAttributeTuples(Relation indexRelation, int numatts);
static void UpdateIndexRelation(Oid indexoid, Oid heapoid,
IndexInfo *indexInfo,
Oid *classOids,
bool primary);
static Oid IndexGetRelation(Oid indexId);
static bool reindexing = false;
bool
SetReindexProcessing(bool reindexmode)
{
bool old = reindexing;
reindexing = reindexmode;
return old;
}
bool
IsReindexProcessing(void)
{
return reindexing;
}
/*
* ConstructTupleDescriptor
*
* Build an index tuple descriptor for a new index
*/
static TupleDesc
ConstructTupleDescriptor(Relation heapRelation,
IndexInfo *indexInfo,
Oid *classObjectId)
{
int numatts = indexInfo->ii_NumIndexAttrs;
List *indexprs = indexInfo->ii_Expressions;
TupleDesc heapTupDesc;
TupleDesc indexTupDesc;
int natts; /* #atts in heap rel --- for error checks */
int i;
heapTupDesc = RelationGetDescr(heapRelation);
natts = RelationGetForm(heapRelation)->relnatts;
/*
* allocate the new tuple descriptor
*/
indexTupDesc = CreateTemplateTupleDesc(numatts, false);
/*
* For simple index columns, we copy the pg_attribute row from the
* parent relation and modify it as necessary. For expressions we
* have to cons up a pg_attribute row the hard way.
*/
for (i = 0; i < numatts; i++)
{
AttrNumber atnum = indexInfo->ii_KeyAttrNumbers[i];
Form_pg_attribute to;
HeapTuple tuple;
Form_pg_type typeTup;
Oid keyType;
indexTupDesc->attrs[i] = to =
(Form_pg_attribute) palloc0(ATTRIBUTE_TUPLE_SIZE);
if (atnum != 0)
{
/* Simple index column */
Form_pg_attribute from;
if (atnum < 0)
{
/*
* here we are indexing on a system attribute (-1...-n)
*/
from = SystemAttributeDefinition(atnum,
heapRelation->rd_rel->relhasoids);
}
else
{
/*
* here we are indexing on a normal attribute (1...n)
*/
if (atnum > natts) /* safety check */
elog(ERROR, "invalid column number %d", atnum);
from = heapTupDesc->attrs[AttrNumberGetAttrOffset(atnum)];
}
/*
* now that we've determined the "from", let's copy the tuple
* desc data...
*/
memcpy(to, from, ATTRIBUTE_TUPLE_SIZE);
/*
* Fix the stuff that should not be the same as the underlying
* attr
*/
to->attnum = i + 1;
to->attstattarget = 0;
to->attcacheoff = -1;
to->attnotnull = false;
to->atthasdef = false;
to->attislocal = true;
to->attinhcount = 0;
}
else
{
/* Expressional index */
Node *indexkey;
if (indexprs == NIL) /* shouldn't happen */
elog(ERROR, "too few entries in indexprs list");
indexkey = (Node *) lfirst(indexprs);
indexprs = lnext(indexprs);
/*
* Make the attribute's name "pg_expresssion_nnn" (maybe think
* of something better later)
*/
sprintf(NameStr(to->attname), "pg_expression_%d", i + 1);
/*
* Lookup the expression type in pg_type for the type length
* etc.
*/
keyType = exprType(indexkey);
tuple = SearchSysCache(TYPEOID,
ObjectIdGetDatum(keyType),
0, 0, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for type %u", keyType);
typeTup = (Form_pg_type) GETSTRUCT(tuple);
/*
* Assign some of the attributes values. Leave the rest as 0.
*/
to->attnum = i + 1;
to->atttypid = keyType;
to->attlen = typeTup->typlen;
to->attbyval = typeTup->typbyval;
to->attstorage = typeTup->typstorage;
to->attalign = typeTup->typalign;
to->attcacheoff = -1;
to->atttypmod = -1;
to->attislocal = true;
ReleaseSysCache(tuple);
}
/*
* We do not yet have the correct relation OID for the index, so
* just set it invalid for now. InitializeAttributeOids() will
* fix it later.
*/
to->attrelid = InvalidOid;
/*
* Check the opclass to see if it provides a keytype (overriding
* the attribute type).
*/
tuple = SearchSysCache(CLAOID,
ObjectIdGetDatum(classObjectId[i]),
0, 0, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for opclass %u",
classObjectId[i]);
keyType = ((Form_pg_opclass) GETSTRUCT(tuple))->opckeytype;
ReleaseSysCache(tuple);
if (OidIsValid(keyType) && keyType != to->atttypid)
{
/* index value and heap value have different types */
tuple = SearchSysCache(TYPEOID,
ObjectIdGetDatum(keyType),
0, 0, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for type %u", keyType);
typeTup = (Form_pg_type) GETSTRUCT(tuple);
to->atttypid = keyType;
to->atttypmod = -1;
to->attlen = typeTup->typlen;
to->attbyval = typeTup->typbyval;
to->attalign = typeTup->typalign;
to->attstorage = typeTup->typstorage;
ReleaseSysCache(tuple);
}
}
return indexTupDesc;
}
/* ----------------------------------------------------------------
* UpdateRelationRelation
* ----------------------------------------------------------------
*/
static void
UpdateRelationRelation(Relation indexRelation)
{
Relation pg_class;
HeapTuple tuple;
pg_class = heap_openr(RelationRelationName, RowExclusiveLock);
/* XXX Natts_pg_class_fixed is a hack - see pg_class.h */
tuple = heap_addheader(Natts_pg_class_fixed,
true,
CLASS_TUPLE_SIZE,
(void *) indexRelation->rd_rel);
/*
* the new tuple must have the oid already chosen for the index. sure
* would be embarrassing to do this sort of thing in polite company.
*/
HeapTupleSetOid(tuple, RelationGetRelid(indexRelation));
simple_heap_insert(pg_class, tuple);
/* update the system catalog indexes */
CatalogUpdateIndexes(pg_class, tuple);
heap_freetuple(tuple);
heap_close(pg_class, RowExclusiveLock);
}
/* ----------------------------------------------------------------
* InitializeAttributeOids
* ----------------------------------------------------------------
*/
static void
InitializeAttributeOids(Relation indexRelation,
int numatts,
Oid indexoid)
{
TupleDesc tupleDescriptor;
int i;
tupleDescriptor = RelationGetDescr(indexRelation);
for (i = 0; i < numatts; i += 1)
tupleDescriptor->attrs[i]->attrelid = indexoid;
}
/* ----------------------------------------------------------------
* AppendAttributeTuples
* ----------------------------------------------------------------
*/
static void
AppendAttributeTuples(Relation indexRelation, int numatts)
{
Relation pg_attribute;
CatalogIndexState indstate;
TupleDesc indexTupDesc;
HeapTuple new_tuple;
int i;
/*
* open the attribute relation and its indexes
*/
pg_attribute = heap_openr(AttributeRelationName, RowExclusiveLock);
indstate = CatalogOpenIndexes(pg_attribute);
/*
* insert data from new index's tupdesc into pg_attribute
*/
indexTupDesc = RelationGetDescr(indexRelation);
for (i = 0; i < numatts; i++)
{
/*
* There used to be very grotty code here to set these fields, but
* I think it's unnecessary. They should be set already.
*/
Assert(indexTupDesc->attrs[i]->attnum == i + 1);
Assert(indexTupDesc->attrs[i]->attcacheoff == -1);
new_tuple = heap_addheader(Natts_pg_attribute,
false,
ATTRIBUTE_TUPLE_SIZE,
(void *) indexTupDesc->attrs[i]);
simple_heap_insert(pg_attribute, new_tuple);
CatalogIndexInsert(indstate, new_tuple);
heap_freetuple(new_tuple);
}
CatalogCloseIndexes(indstate);
heap_close(pg_attribute, RowExclusiveLock);
}
/* ----------------------------------------------------------------
* UpdateIndexRelation
* ----------------------------------------------------------------
*/
static void
UpdateIndexRelation(Oid indexoid,
Oid heapoid,
IndexInfo *indexInfo,
Oid *classOids,
bool primary)
{
int16 indkey[INDEX_MAX_KEYS];
Oid indclass[INDEX_MAX_KEYS];
Datum exprsDatum;
Datum predDatum;
Datum values[Natts_pg_index];
char nulls[Natts_pg_index];
Relation pg_index;
HeapTuple tuple;
int i;
/*
* Copy the index key and opclass info into zero-filled vectors
*/
MemSet(indkey, 0, sizeof(indkey));
MemSet(indclass, 0, sizeof(indclass));
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
indkey[i] = indexInfo->ii_KeyAttrNumbers[i];
indclass[i] = classOids[i];
}
/*
* Convert the index expressions (if any) to a text datum
*/
if (indexInfo->ii_Expressions != NIL)
{
char *exprsString;
exprsString = nodeToString(indexInfo->ii_Expressions);
exprsDatum = DirectFunctionCall1(textin,
CStringGetDatum(exprsString));
pfree(exprsString);
}
else
exprsDatum = (Datum) 0;
/*
* Convert the index predicate (if any) to a text datum
*/
if (indexInfo->ii_Predicate != NIL)
{
char *predString;
predString = nodeToString(indexInfo->ii_Predicate);
predDatum = DirectFunctionCall1(textin,
CStringGetDatum(predString));
pfree(predString);
}
else
predDatum = (Datum) 0;
/*
* open the system catalog index relation
*/
pg_index = heap_openr(IndexRelationName, RowExclusiveLock);
/*
* Build a pg_index tuple
*/
MemSet(nulls, ' ', sizeof(nulls));
values[Anum_pg_index_indexrelid - 1] = ObjectIdGetDatum(indexoid);
values[Anum_pg_index_indrelid - 1] = ObjectIdGetDatum(heapoid);
values[Anum_pg_index_indkey - 1] = PointerGetDatum(indkey);
values[Anum_pg_index_indclass - 1] = PointerGetDatum(indclass);
values[Anum_pg_index_indnatts - 1] = Int16GetDatum(indexInfo->ii_NumIndexAttrs);
values[Anum_pg_index_indisunique - 1] = BoolGetDatum(indexInfo->ii_Unique);
values[Anum_pg_index_indisprimary - 1] = BoolGetDatum(primary);
values[Anum_pg_index_indisclustered - 1] = BoolGetDatum(false);
values[Anum_pg_index_indexprs - 1] = exprsDatum;
if (exprsDatum == (Datum) 0)
nulls[Anum_pg_index_indexprs - 1] = 'n';
values[Anum_pg_index_indpred - 1] = predDatum;
if (predDatum == (Datum) 0)
nulls[Anum_pg_index_indpred - 1] = 'n';
tuple = heap_formtuple(RelationGetDescr(pg_index), values, nulls);
/*
* insert the tuple into the pg_index catalog
*/
simple_heap_insert(pg_index, tuple);
/* update the indexes on pg_index */
CatalogUpdateIndexes(pg_index, tuple);
/*
* close the relation and free the tuple
*/
heap_close(pg_index, RowExclusiveLock);
heap_freetuple(tuple);
}
/* ----------------------------------------------------------------
* index_create
*
* Returns OID of the created index.
* ----------------------------------------------------------------
*/
Oid
index_create(Oid heapRelationId,
const char *indexRelationName,
IndexInfo *indexInfo,
Oid accessMethodObjectId,
Oid *classObjectId,
bool primary,
bool isconstraint,
bool allow_system_table_mods)
{
Relation heapRelation;
Relation indexRelation;
TupleDesc indexTupDesc;
bool shared_relation;
Oid namespaceId;
Oid indexoid;
int i;
SetReindexProcessing(false);
/*
* Only SELECT ... FOR UPDATE are allowed while doing this
*/
heapRelation = heap_open(heapRelationId, ShareLock);
/*
* The index will be in the same namespace as its parent table, and is
* shared across databases if and only if the parent is.
*/
namespaceId = RelationGetNamespace(heapRelation);
shared_relation = heapRelation->rd_rel->relisshared;
/*
* check parameters
*/
if (indexInfo->ii_NumIndexAttrs < 1)
elog(ERROR, "must index at least one column");
if (!allow_system_table_mods &&
IsSystemRelation(heapRelation) &&
IsNormalProcessingMode())
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("user-defined indexes on system catalogs are not supported")));
/*
* We cannot allow indexing a shared relation after initdb (because
* there's no way to make the entry in other databases' pg_class).
* Unfortunately we can't distinguish initdb from a manually started
* standalone backend. However, we can at least prevent this mistake
* under normal multi-user operation.
*/
if (shared_relation && IsUnderPostmaster)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("shared indexes cannot be created after initdb")));
if (get_relname_relid(indexRelationName, namespaceId))
ereport(ERROR,
(errcode(ERRCODE_DUPLICATE_TABLE),
errmsg("relation \"%s\" already exists",
indexRelationName)));
/*
* construct tuple descriptor for index tuples
*/
indexTupDesc = ConstructTupleDescriptor(heapRelation,
indexInfo,
classObjectId);
/*
* create the index relation's relcache entry and physical disk file.
* (If we fail further down, it's the smgr's responsibility to remove
* the disk file again.)
*/
indexRelation = heap_create(indexRelationName,
namespaceId,
indexTupDesc,
shared_relation,
true,
allow_system_table_mods);
/* Fetch the relation OID assigned by heap_create */
indexoid = RelationGetRelid(indexRelation);
/*
* Obtain exclusive lock on it. Although no other backends can see it
* until we commit, this prevents deadlock-risk complaints from lock
* manager in cases such as CLUSTER.
*/
LockRelation(indexRelation, AccessExclusiveLock);
/*
* Fill in fields of the index's pg_class entry that are not set
* correctly by heap_create.
*
* XXX should have a cleaner way to create cataloged indexes
*/
indexRelation->rd_rel->relowner = GetUserId();
indexRelation->rd_rel->relam = accessMethodObjectId;
indexRelation->rd_rel->relkind = RELKIND_INDEX;
indexRelation->rd_rel->relhasoids = false;
/*
* store index's pg_class entry
*/
UpdateRelationRelation(indexRelation);
/*
* now update the object id's of all the attribute tuple forms in the
* index relation's tuple descriptor
*/
InitializeAttributeOids(indexRelation,
indexInfo->ii_NumIndexAttrs,
indexoid);
/*
* append ATTRIBUTE tuples for the index
*/
AppendAttributeTuples(indexRelation, indexInfo->ii_NumIndexAttrs);
/* ----------------
* update pg_index
* (append INDEX tuple)
*
* Note that this stows away a representation of "predicate".
* (Or, could define a rule to maintain the predicate) --Nels, Feb '92
* ----------------
*/
UpdateIndexRelation(indexoid, heapRelationId, indexInfo,
classObjectId, primary);
/*
* Register constraint and dependencies for the index.
*
* If the index is from a CONSTRAINT clause, construct a pg_constraint
* entry. The index is then linked to the constraint, which in turn
* is linked to the table. If it's not a CONSTRAINT, make the
* dependency directly on the table.
*
* We don't need a dependency on the namespace, because there'll be an
* indirect dependency via our parent table.
*
* During bootstrap we can't register any dependencies, and we don't try
* to make a constraint either.
*/
if (!IsBootstrapProcessingMode())
{
ObjectAddress myself,
referenced;
myself.classId = RelOid_pg_class;
myself.objectId = indexoid;
myself.objectSubId = 0;
if (isconstraint)
{
char constraintType;
Oid conOid;
if (primary)
constraintType = CONSTRAINT_PRIMARY;
else if (indexInfo->ii_Unique)
constraintType = CONSTRAINT_UNIQUE;
else
{
elog(ERROR, "constraint must be PRIMARY or UNIQUE");
constraintType = 0; /* keep compiler quiet */
}
/* Shouldn't have any expressions */
if (indexInfo->ii_Expressions)
elog(ERROR, "constraints can't have index expressions");
conOid = CreateConstraintEntry(indexRelationName,
namespaceId,
constraintType,
false, /* isDeferrable */
false, /* isDeferred */
heapRelationId,
indexInfo->ii_KeyAttrNumbers,
indexInfo->ii_NumIndexAttrs,
InvalidOid, /* no domain */
InvalidOid, /* no foreign key */
NULL,
0,
' ',
' ',
' ',
InvalidOid, /* no associated index */
NULL, /* no check constraint */
NULL,
NULL);
referenced.classId = get_system_catalog_relid(ConstraintRelationName);
referenced.objectId = conOid;
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_INTERNAL);
}
else
{
/* Create auto dependencies on simply-referenced columns */
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
if (indexInfo->ii_KeyAttrNumbers[i] != 0)
{
referenced.classId = RelOid_pg_class;
referenced.objectId = heapRelationId;
referenced.objectSubId = indexInfo->ii_KeyAttrNumbers[i];
recordDependencyOn(&myself, &referenced, DEPENDENCY_AUTO);
}
}
}
/* Store dependency on operator classes */
referenced.classId = get_system_catalog_relid(OperatorClassRelationName);
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
referenced.objectId = classObjectId[i];
referenced.objectSubId = 0;
recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
}
/* Store dependencies on anything mentioned in index expressions */
if (indexInfo->ii_Expressions)
{
recordDependencyOnSingleRelExpr(&myself,
(Node *) indexInfo->ii_Expressions,
heapRelationId,
DEPENDENCY_NORMAL,
DEPENDENCY_AUTO);
}
/* Store dependencies on anything mentioned in predicate */
if (indexInfo->ii_Predicate)
{
recordDependencyOnSingleRelExpr(&myself,
(Node *) indexInfo->ii_Predicate,
heapRelationId,
DEPENDENCY_NORMAL,
DEPENDENCY_AUTO);
}
}
/*
* Fill in the index strategy structure with information from the
* catalogs. First we must advance the command counter so that we
* will see the newly-entered index catalog tuples.
*/
CommandCounterIncrement();
RelationInitIndexAccessInfo(indexRelation);
/*
* If this is bootstrap (initdb) time, then we don't actually fill in
* the index yet. We'll be creating more indexes and classes later,
* so we delay filling them in until just before we're done with
* bootstrapping. Otherwise, we call the routine that constructs the
* index.
*
* In normal processing mode, the heap and index relations are closed by
* index_build() --- but we continue to hold the ShareLock on the heap
* and the exclusive lock on the index that we acquired above, until
* end of transaction.
*/
if (IsBootstrapProcessingMode())
{
index_register(heapRelationId, indexoid, indexInfo);
/* XXX shouldn't we close the heap and index rels here? */
}
else
index_build(heapRelation, indexRelation, indexInfo);
return indexoid;
}
/*
* index_drop
*
* NOTE: this routine should now only be called through performDeletion(),
* else associated dependencies won't be cleaned up.
*/
void
index_drop(Oid indexId)
{
Oid heapId;
Relation userHeapRelation;
Relation userIndexRelation;
Relation indexRelation;
HeapTuple tuple;
int i;
Assert(OidIsValid(indexId));
/*
* To drop an index safely, we must grab exclusive lock on its parent
* table; otherwise there could be other backends using the index!
* Exclusive lock on the index alone is insufficient because another
* backend might be in the midst of devising a query plan that will
* use the index. The parser and planner take care to hold an
* appropriate lock on the parent table while working, but having them
* hold locks on all the indexes too seems overly complex. We do grab
* exclusive lock on the index too, just to be safe. Both locks must
* be held till end of transaction, else other backends will still see
* this index in pg_index.
*/
heapId = IndexGetRelation(indexId);
userHeapRelation = heap_open(heapId, AccessExclusiveLock);
userIndexRelation = index_open(indexId);
LockRelation(userIndexRelation, AccessExclusiveLock);
/*
* fix RELATION relation
*/
DeleteRelationTuple(indexId);
/*
* fix ATTRIBUTE relation
*/
DeleteAttributeTuples(indexId);
/*
* fix INDEX relation
*/
indexRelation = heap_openr(IndexRelationName, RowExclusiveLock);
tuple = SearchSysCache(INDEXRELID,
ObjectIdGetDatum(indexId),
0, 0, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for index %u", indexId);
simple_heap_delete(indexRelation, &tuple->t_self);
ReleaseSysCache(tuple);
heap_close(indexRelation, RowExclusiveLock);
/*
* flush buffer cache and physically remove the file
*/
i = FlushRelationBuffers(userIndexRelation, (BlockNumber) 0);
if (i < 0)
elog(ERROR, "FlushRelationBuffers returned %d", i);
smgrunlink(DEFAULT_SMGR, userIndexRelation);
/*
* We are presently too lazy to attempt to compute the new correct
* value of relhasindex (the next VACUUM will fix it if necessary). So
* there is no need to update the pg_class tuple for the owning
* relation. But we must send out a shared-cache-inval notice on the
* owning relation to ensure other backends update their relcache
* lists of indexes.
*/
CacheInvalidateRelcache(heapId);
/*
* Close rels, but keep locks
*/
index_close(userIndexRelation);
heap_close(userHeapRelation, NoLock);
RelationForgetRelation(indexId);
}
/* ----------------------------------------------------------------
* index_build support
* ----------------------------------------------------------------
*/
/* ----------------
* BuildIndexInfo
* Construct an IndexInfo record for an open index
*
* IndexInfo stores the information about the index that's needed by
* FormIndexDatum, which is used for both index_build() and later insertion
* of individual index tuples. Normally we build an IndexInfo for an index
* just once per command, and then use it for (potentially) many tuples.
* ----------------
*/
IndexInfo *
BuildIndexInfo(Relation index)
{
IndexInfo *ii = makeNode(IndexInfo);
Form_pg_index indexStruct = index->rd_index;
int i;
int numKeys;
/* check the number of keys, and copy attr numbers into the IndexInfo */
numKeys = indexStruct->indnatts;
if (numKeys < 1 || numKeys > INDEX_MAX_KEYS)
elog(ERROR, "invalid indnatts %d for index %u",
numKeys, RelationGetRelid(index));
ii->ii_NumIndexAttrs = numKeys;
for (i = 0; i < numKeys; i++)
ii->ii_KeyAttrNumbers[i] = indexStruct->indkey[i];
/* fetch any expressions needed for expressional indexes */
ii->ii_Expressions = RelationGetIndexExpressions(index);
ii->ii_ExpressionsState = NIL;
/* fetch index predicate if any */
ii->ii_Predicate = RelationGetIndexPredicate(index);
ii->ii_PredicateState = NIL;
/* other info */
ii->ii_Unique = indexStruct->indisunique;
return ii;
}
/* ----------------
* FormIndexDatum
* Construct Datum[] and nullv[] arrays for a new index tuple.
*
* indexInfo Info about the index
* heapTuple Heap tuple for which we must prepare an index entry
* heapDescriptor tupledesc for heap tuple
* estate executor state for evaluating any index expressions
* datum Array of index Datums (output area)
* nullv Array of is-null indicators (output area)
*
* When there are no index expressions, estate may be NULL. Otherwise it
* must be supplied, *and* the ecxt_scantuple slot of its per-tuple expr
* context must point to the heap tuple passed in.
*
* For largely historical reasons, we don't actually call index_formtuple()
* here, we just prepare its input arrays datum[] and nullv[].
* ----------------
*/
void
FormIndexDatum(IndexInfo *indexInfo,
HeapTuple heapTuple,
TupleDesc heapDescriptor,
EState *estate,
Datum *datum,
char *nullv)
{
List *indexprs;
int i;
if (indexInfo->ii_Expressions != NIL &&
indexInfo->ii_ExpressionsState == NIL)
{
/* First time through, set up expression evaluation state */
indexInfo->ii_ExpressionsState = (List *)
ExecPrepareExpr((Expr *) indexInfo->ii_Expressions,
estate);
/* Check caller has set up context correctly */
Assert(GetPerTupleExprContext(estate)->ecxt_scantuple->val == heapTuple);
}
indexprs = indexInfo->ii_ExpressionsState;
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
int keycol = indexInfo->ii_KeyAttrNumbers[i];
Datum iDatum;
bool isNull;
if (keycol != 0)
{
/*
* Plain index column; get the value we need directly from the
* heap tuple.
*/
iDatum = heap_getattr(heapTuple, keycol, heapDescriptor, &isNull);
}
else
{
/*
* Index expression --- need to evaluate it.
*/
if (indexprs == NIL)
elog(ERROR, "wrong number of index expressions");
iDatum = ExecEvalExprSwitchContext((ExprState *) lfirst(indexprs),
GetPerTupleExprContext(estate),
&isNull,
NULL);
indexprs = lnext(indexprs);
}
datum[i] = iDatum;
nullv[i] = (isNull) ? 'n' : ' ';
}
if (indexprs != NIL)
elog(ERROR, "wrong number of index expressions");
}
/* ---------------------------------------------
* Indexes of the relation active ?
*
* Caller must hold an adequate lock on the relation to ensure the
* answer won't be changing.
* ---------------------------------------------
*/
bool
IndexesAreActive(Relation heaprel)
{
bool isactive;
Relation indexRelation;
HeapScanDesc scan;
ScanKeyData entry;
if (heaprel->rd_rel->relkind != RELKIND_RELATION &&
heaprel->rd_rel->relkind != RELKIND_TOASTVALUE)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("relation \"%s\" isn't an indexable relation",
RelationGetRelationName(heaprel))));
/* If pg_class.relhasindex is set, indexes are active */
isactive = heaprel->rd_rel->relhasindex;
if (isactive)
return isactive;
/* Otherwise, look to see if there are any indexes */
indexRelation = heap_openr(IndexRelationName, AccessShareLock);
ScanKeyEntryInitialize(&entry, 0,
Anum_pg_index_indrelid, F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(heaprel)));
scan = heap_beginscan(indexRelation, SnapshotNow, 1, &entry);
if (heap_getnext(scan, ForwardScanDirection) == NULL)
isactive = true; /* no indexes, so report "active" */
heap_endscan(scan);
heap_close(indexRelation, AccessShareLock);
return isactive;
}
/* ----------------
* set relhasindex of relation's pg_class entry
*
* If isprimary is TRUE, we are defining a primary index, so also set
* relhaspkey to TRUE. Otherwise, leave relhaspkey alone.
*
* If reltoastidxid is not InvalidOid, also set reltoastidxid to that value.
* This is only used for TOAST relations.
*
* NOTE: an important side-effect of this operation is that an SI invalidation
* message is sent out to all backends --- including me --- causing relcache
* entries to be flushed or updated with the new hasindex data. This must
* happen even if we find that no change is needed in the pg_class row.
* ----------------
*/
void
setRelhasindex(Oid relid, bool hasindex, bool isprimary, Oid reltoastidxid)
{
Relation pg_class;
HeapTuple tuple;
Form_pg_class classtuple;
bool dirty = false;
HeapScanDesc pg_class_scan = NULL;
/*
* Find the tuple to update in pg_class.
*/
pg_class = heap_openr(RelationRelationName, RowExclusiveLock);
if (!IsIgnoringSystemIndexes() &&
(!IsReindexProcessing() || pg_class->rd_rel->relhasindex))
{
tuple = SearchSysCacheCopy(RELOID,
ObjectIdGetDatum(relid),
0, 0, 0);
}
else
{
ScanKeyData key[1];
ScanKeyEntryInitialize(&key[0], 0,
ObjectIdAttributeNumber,
F_OIDEQ,
ObjectIdGetDatum(relid));
pg_class_scan = heap_beginscan(pg_class, SnapshotNow, 1, key);
tuple = heap_getnext(pg_class_scan, ForwardScanDirection);
}
if (!HeapTupleIsValid(tuple))
elog(ERROR, "could not find tuple for relation %u", relid);
/*
* Update fields in the pg_class tuple.
*/
if (pg_class_scan)
LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_EXCLUSIVE);
classtuple = (Form_pg_class) GETSTRUCT(tuple);
if (classtuple->relhasindex != hasindex)
{
classtuple->relhasindex = hasindex;
dirty = true;
}
if (isprimary)
{
if (!classtuple->relhaspkey)
{
classtuple->relhaspkey = true;
dirty = true;
}
}
if (OidIsValid(reltoastidxid))
{
Assert(classtuple->relkind == RELKIND_TOASTVALUE);
if (classtuple->reltoastidxid != reltoastidxid)
{
classtuple->reltoastidxid = reltoastidxid;
dirty = true;
}
}
if (pg_class_scan)
LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
if (pg_class_scan)
{
/* Write the modified tuple in-place */
WriteNoReleaseBuffer(pg_class_scan->rs_cbuf);
/* Send out shared cache inval if necessary */
if (!IsBootstrapProcessingMode())
CacheInvalidateHeapTuple(pg_class, tuple);
BufferSync();
}
else if (dirty)
{
simple_heap_update(pg_class, &tuple->t_self, tuple);
/* Keep the catalog indexes up to date */
CatalogUpdateIndexes(pg_class, tuple);
}
else
{
/* no need to change tuple, but force relcache rebuild anyway */
CacheInvalidateRelcache(relid);
}
if (!pg_class_scan)
heap_freetuple(tuple);
else
heap_endscan(pg_class_scan);
heap_close(pg_class, RowExclusiveLock);
}
/*
* setNewRelfilenode - assign a new relfilenode value to the relation
*
* Caller must already hold exclusive lock on the relation.
*/
void
setNewRelfilenode(Relation relation)
{
Oid newrelfilenode;
Relation pg_class;
HeapTuple tuple;
Form_pg_class rd_rel;
HeapScanDesc pg_class_scan = NULL;
bool in_place_upd;
RelationData workrel;
Assert(!IsSystemRelation(relation) || IsToastRelation(relation) ||
relation->rd_rel->relkind == RELKIND_INDEX);
/* Allocate a new relfilenode */
newrelfilenode = newoid();
/*
* Find the RELATION relation tuple for the given relation.
*/
pg_class = heap_openr(RelationRelationName, RowExclusiveLock);
in_place_upd = IsIgnoringSystemIndexes();
if (!in_place_upd)
{
tuple = SearchSysCacheCopy(RELOID,
ObjectIdGetDatum(RelationGetRelid(relation)),
0, 0, 0);
}
else
{
ScanKeyData key[1];
ScanKeyEntryInitialize(&key[0], 0,
ObjectIdAttributeNumber,
F_OIDEQ,
ObjectIdGetDatum(RelationGetRelid(relation)));
pg_class_scan = heap_beginscan(pg_class, SnapshotNow, 1, key);
tuple = heap_getnext(pg_class_scan, ForwardScanDirection);
}
if (!HeapTupleIsValid(tuple))
elog(ERROR, "could not find tuple for relation %u",
RelationGetRelid(relation));
rd_rel = (Form_pg_class) GETSTRUCT(tuple);
/* schedule unlinking old relfilenode */
smgrunlink(DEFAULT_SMGR, relation);
/* create another storage file. Is it a little ugly ? */
memcpy((char *) &workrel, relation, sizeof(RelationData));
workrel.rd_fd = -1;
workrel.rd_node.relNode = newrelfilenode;
heap_storage_create(&workrel);
smgrclose(DEFAULT_SMGR, &workrel);
/* update the pg_class row */
if (in_place_upd)
{
LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_EXCLUSIVE);
rd_rel->relfilenode = newrelfilenode;
LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
WriteNoReleaseBuffer(pg_class_scan->rs_cbuf);
BufferSync();
/* Send out shared cache inval if necessary */
if (!IsBootstrapProcessingMode())
CacheInvalidateHeapTuple(pg_class, tuple);
}
else
{
rd_rel->relfilenode = newrelfilenode;
simple_heap_update(pg_class, &tuple->t_self, tuple);
CatalogUpdateIndexes(pg_class, tuple);
}
if (!pg_class_scan)
heap_freetuple(tuple);
else
heap_endscan(pg_class_scan);
heap_close(pg_class, RowExclusiveLock);
/* Make sure the relfilenode change is visible */
CommandCounterIncrement();
}
/* ----------------
* UpdateStats
*
* Update pg_class' relpages and reltuples statistics for the given relation
* (which can be either a table or an index). Note that this is not used
* in the context of VACUUM.
* ----------------
*/
void
UpdateStats(Oid relid, double reltuples)
{
Relation whichRel;
Relation pg_class;
HeapTuple tuple;
BlockNumber relpages;
Form_pg_class rd_rel;
HeapScanDesc pg_class_scan = NULL;
bool in_place_upd;
/*
* This routine handles updates for both the heap and index relation
* statistics. In order to guarantee that we're able to *see* the
* index relation tuple, we bump the command counter id here. The
* index relation tuple was created in the current transaction.
*/
CommandCounterIncrement();
/*
* CommandCounterIncrement() flushes invalid cache entries, including
* those for the heap and index relations for which we're updating
* statistics. Now that the cache is flushed, it's safe to open the
* relation again. We need the relation open in order to figure out
* how many blocks it contains.
*/
/*
* Grabbing lock here is probably redundant ...
*/
whichRel = relation_open(relid, ShareLock);
/*
* Find the RELATION relation tuple for the given relation.
*/
pg_class = heap_openr(RelationRelationName, RowExclusiveLock);
in_place_upd = (IsIgnoringSystemIndexes() || IsReindexProcessing());
if (!in_place_upd)
{
tuple = SearchSysCacheCopy(RELOID,
ObjectIdGetDatum(relid),
0, 0, 0);
}
else
{
ScanKeyData key[1];
ScanKeyEntryInitialize(&key[0], 0,
ObjectIdAttributeNumber,
F_OIDEQ,
ObjectIdGetDatum(relid));
pg_class_scan = heap_beginscan(pg_class, SnapshotNow, 1, key);
tuple = heap_getnext(pg_class_scan, ForwardScanDirection);
}
if (!HeapTupleIsValid(tuple))
elog(ERROR, "could not find tuple for relation %u", relid);
/*
* Figure values to insert.
*
* If we found zero tuples in the scan, do NOT believe it; instead put a
* bogus estimate into the statistics fields. Otherwise, the common
* pattern "CREATE TABLE; CREATE INDEX; insert data" leaves the table
* with zero size statistics until a VACUUM is done. The optimizer
* will generate very bad plans if the stats claim the table is empty
* when it is actually sizable. See also CREATE TABLE in heap.c.
*
* Note: this path is also taken during bootstrap, because bootstrap.c
* passes reltuples = 0 after loading a table. We have to estimate
* some number for reltuples based on the actual number of pages.
*/
relpages = RelationGetNumberOfBlocks(whichRel);
if (reltuples == 0)
{
if (relpages == 0)
{
/* Bogus defaults for a virgin table, same as heap.c */
reltuples = 1000;
relpages = 10;
}
else if (whichRel->rd_rel->relkind == RELKIND_INDEX && relpages <= 2)
{
/* Empty index, leave bogus defaults in place */
reltuples = 1000;
}
else
reltuples = ((double) relpages) * NTUPLES_PER_PAGE(whichRel->rd_rel->relnatts);
}
/*
* Update statistics in pg_class, if they changed. (Avoiding an
* unnecessary update is not just a tiny performance improvement; it
* also reduces the window wherein concurrent CREATE INDEX commands
* may conflict.)
*/
rd_rel = (Form_pg_class) GETSTRUCT(tuple);
if (rd_rel->relpages != (int32) relpages ||
rd_rel->reltuples != (float4) reltuples)
{
if (in_place_upd)
{
/*
* At bootstrap time, we don't need to worry about concurrency
* or visibility of changes, so we cheat. Also cheat if
* REINDEX.
*/
LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_EXCLUSIVE);
rd_rel->relpages = (int32) relpages;
rd_rel->reltuples = (float4) reltuples;
LockBuffer(pg_class_scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
WriteNoReleaseBuffer(pg_class_scan->rs_cbuf);
if (!IsBootstrapProcessingMode())
CacheInvalidateHeapTuple(pg_class, tuple);
}
else
{
/* During normal processing, must work harder. */
rd_rel->relpages = (int32) relpages;
rd_rel->reltuples = (float4) reltuples;
simple_heap_update(pg_class, &tuple->t_self, tuple);
CatalogUpdateIndexes(pg_class, tuple);
}
}
if (!pg_class_scan)
heap_freetuple(tuple);
else
heap_endscan(pg_class_scan);
/*
* We shouldn't have to do this, but we do... Modify the reldesc in
* place with the new values so that the cache contains the latest
* copy. (XXX is this really still necessary? The relcache will get
* fixed at next CommandCounterIncrement, so why bother here?)
*/
whichRel->rd_rel->relpages = (int32) relpages;
whichRel->rd_rel->reltuples = (float4) reltuples;
heap_close(pg_class, RowExclusiveLock);
relation_close(whichRel, NoLock);
}
/*
* index_build - invoke access-method-specific index build procedure
*/
void
index_build(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo)
{
RegProcedure procedure;
/*
* sanity checks
*/
Assert(RelationIsValid(indexRelation));
Assert(PointerIsValid(indexRelation->rd_am));
procedure = indexRelation->rd_am->ambuild;
Assert(RegProcedureIsValid(procedure));
/*
* Call the access method's build procedure
*/
OidFunctionCall3(procedure,
PointerGetDatum(heapRelation),
PointerGetDatum(indexRelation),
PointerGetDatum(indexInfo));
}
/*
* IndexBuildHeapScan - scan the heap relation to find tuples to be indexed
*
* This is called back from an access-method-specific index build procedure
* after the AM has done whatever setup it needs. The parent heap relation
* is scanned to find tuples that should be entered into the index. Each
* such tuple is passed to the AM's callback routine, which does the right
* things to add it to the new index. After we return, the AM's index
* build procedure does whatever cleanup is needed; in particular, it should
* close the heap and index relations.
*
* The total count of heap tuples is returned. This is for updating pg_class
* statistics. (It's annoying not to be able to do that here, but we can't
* do it until after the relation is closed.) Note that the index AM itself
* must keep track of the number of index tuples; we don't do so here because
* the AM might reject some of the tuples for its own reasons, such as being
* unable to store NULLs.
*/
double
IndexBuildHeapScan(Relation heapRelation,
Relation indexRelation,
IndexInfo *indexInfo,
IndexBuildCallback callback,
void *callback_state)
{
HeapScanDesc scan;
HeapTuple heapTuple;
TupleDesc heapDescriptor;
Datum attdata[INDEX_MAX_KEYS];
char nulls[INDEX_MAX_KEYS];
double reltuples;
List *predicate;
TupleTable tupleTable;
TupleTableSlot *slot;
EState *estate;
ExprContext *econtext;
Snapshot snapshot;
TransactionId OldestXmin;
/*
* sanity checks
*/
Assert(OidIsValid(indexRelation->rd_rel->relam));
heapDescriptor = RelationGetDescr(heapRelation);
/*
* Need an EState for evaluation of index expressions and
* partial-index predicates.
*/
estate = CreateExecutorState();
econtext = GetPerTupleExprContext(estate);
/*
* If this is a predicate (partial) index, we will need to evaluate
* the predicate using ExecQual, which requires the current tuple to
* be in a slot of a TupleTable. Likewise if there are any
* expressions.
*/
if (indexInfo->ii_Predicate != NIL || indexInfo->ii_Expressions != NIL)
{
tupleTable = ExecCreateTupleTable(1);
slot = ExecAllocTableSlot(tupleTable);
ExecSetSlotDescriptor(slot, heapDescriptor, false);
/* Arrange for econtext's scan tuple to be the tuple under test */
econtext->ecxt_scantuple = slot;
/* Set up execution state for predicate. */
predicate = (List *)
ExecPrepareExpr((Expr *) indexInfo->ii_Predicate,
estate);
}
else
{
tupleTable = NULL;
slot = NULL;
predicate = NIL;
}
/*
* Ok, begin our scan of the base relation. We use SnapshotAny
* because we must retrieve all tuples and do our own time qual
* checks.
*/
if (IsBootstrapProcessingMode())
{
snapshot = SnapshotNow;
OldestXmin = InvalidTransactionId;
}
else
{
snapshot = SnapshotAny;
OldestXmin = GetOldestXmin(heapRelation->rd_rel->relisshared);
}
scan = heap_beginscan(heapRelation, /* relation */
snapshot, /* seeself */
0, /* number of keys */
(ScanKey) NULL); /* scan key */
reltuples = 0;
/*
* Scan all tuples in the base relation.
*/
while ((heapTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
bool tupleIsAlive;
CHECK_FOR_INTERRUPTS();
if (snapshot == SnapshotAny)
{
/* do our own time qual check */
bool indexIt;
uint16 sv_infomask;
/*
* HeapTupleSatisfiesVacuum may update tuple's hint status
* bits. We could possibly get away with not locking the
* buffer here, since caller should hold ShareLock on the
* relation, but let's be conservative about it.
*/
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE);
sv_infomask = heapTuple->t_data->t_infomask;
switch (HeapTupleSatisfiesVacuum(heapTuple->t_data, OldestXmin))
{
case HEAPTUPLE_DEAD:
indexIt = false;
tupleIsAlive = false;
break;
case HEAPTUPLE_LIVE:
indexIt = true;
tupleIsAlive = true;
break;
case HEAPTUPLE_RECENTLY_DEAD:
/*
* If tuple is recently deleted then we must index it
* anyway to keep VACUUM from complaining.
*/
indexIt = true;
tupleIsAlive = false;
break;
case HEAPTUPLE_INSERT_IN_PROGRESS:
/*
* Since caller should hold ShareLock or better, we
* should not see any tuples inserted by open
* transactions --- unless it's our own transaction.
* (Consider INSERT followed by CREATE INDEX within a
* transaction.)
*/
if (!TransactionIdIsCurrentTransactionId(
HeapTupleHeaderGetXmin(heapTuple->t_data)))
elog(ERROR, "concurrent insert in progress");
indexIt = true;
tupleIsAlive = true;
break;
case HEAPTUPLE_DELETE_IN_PROGRESS:
/*
* Since caller should hold ShareLock or better, we
* should not see any tuples deleted by open
* transactions --- unless it's our own transaction.
* (Consider DELETE followed by CREATE INDEX within a
* transaction.)
*/
if (!TransactionIdIsCurrentTransactionId(
HeapTupleHeaderGetXmax(heapTuple->t_data)))
elog(ERROR, "concurrent delete in progress");
indexIt = true;
tupleIsAlive = false;
break;
default:
elog(ERROR, "unexpected HeapTupleSatisfiesVacuum result");
indexIt = tupleIsAlive = false; /* keep compiler quiet */
break;
}
/* check for hint-bit update by HeapTupleSatisfiesVacuum */
if (sv_infomask != heapTuple->t_data->t_infomask)
SetBufferCommitInfoNeedsSave(scan->rs_cbuf);
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
if (!indexIt)
continue;
}
else
{
/* heap_getnext did the time qual check */
tupleIsAlive = true;
}
reltuples += 1;
MemoryContextReset(econtext->ecxt_per_tuple_memory);
/* Set up for predicate or expression evaluation */
if (slot)
ExecStoreTuple(heapTuple, slot, InvalidBuffer, false);
/*
* In a partial index, discard tuples that don't satisfy the
* predicate. We can also discard recently-dead tuples, since
* VACUUM doesn't complain about tuple count mismatch for partial
* indexes.
*/
if (predicate != NIL)
{
if (!tupleIsAlive)
continue;
if (!ExecQual(predicate, econtext, false))
continue;
}
/*
* For the current heap tuple, extract all the attributes we use
* in this index, and note which are null. This also performs
* evaluation of any expressions needed.
*/
FormIndexDatum(indexInfo,
heapTuple,
heapDescriptor,
estate,
attdata,
nulls);
/*
* You'd think we should go ahead and build the index tuple here,
* but some index AMs want to do further processing on the data
* first. So pass the attdata and nulls arrays, instead.
*/
/* Call the AM's callback routine to process the tuple */
callback(indexRelation, heapTuple, attdata, nulls, tupleIsAlive,
callback_state);
}
heap_endscan(scan);
if (tupleTable)
ExecDropTupleTable(tupleTable, true);
FreeExecutorState(estate);
/* These may have been pointing to the now-gone estate */
indexInfo->ii_ExpressionsState = NIL;
indexInfo->ii_PredicateState = NIL;
return reltuples;
}
/*
* IndexGetRelation: given an index's relation OID, get the OID of the
* relation it is an index on. Uses the system cache.
*/
static Oid
IndexGetRelation(Oid indexId)
{
HeapTuple tuple;
Form_pg_index index;
Oid result;
tuple = SearchSysCache(INDEXRELID,
ObjectIdGetDatum(indexId),
0, 0, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for index %u", indexId);
index = (Form_pg_index) GETSTRUCT(tuple);
Assert(index->indexrelid == indexId);
result = index->indrelid;
ReleaseSysCache(tuple);
return result;
}
/*
* reindex_index - This routine is used to recreate an index
*/
bool
reindex_index(Oid indexId, bool force, bool inplace)
{
Relation iRel,
heapRelation;
IndexInfo *indexInfo;
Oid heapId;
bool old;
/*
* Open our index relation and get an exclusive lock on it.
*
* Note: doing this before opening the parent heap relation means there's
* a possibility for deadlock failure against another xact that is
* doing normal accesses to the heap and index. However, it's not
* real clear why you'd be needing to do REINDEX on a table that's in
* active use, so I'd rather have the protection of making sure the
* index is locked down.
*/
iRel = index_open(indexId);
LockRelation(iRel, AccessExclusiveLock);
old = SetReindexProcessing(true);
/* Get OID of index's parent table */
heapId = iRel->rd_index->indrelid;
/* Open the parent heap relation */
heapRelation = heap_open(heapId, AccessExclusiveLock);
/*
* If it's a shared index, we must do inplace processing (because we
* have no way to update relfilenode in other databases). Also, if
* it's a nailed-in-cache index, we must do inplace processing because
* the relcache can't cope with changing its relfilenode.
*
* In either of these cases, we are definitely processing a system index,
* so we'd better be ignoring system indexes. (These checks are just
* for paranoia's sake --- upstream code should have disallowed reindex
* in such cases already.)
*/
if (iRel->rd_rel->relisshared)
{
if (!IsIgnoringSystemIndexes())
elog(ERROR,
"must be ignoring system indexes to reindex shared index %u",
indexId);
inplace = true;
}
if (iRel->rd_isnailed)
{
if (!IsIgnoringSystemIndexes())
elog(ERROR,
"must be ignoring system indexes to reindex nailed index %u",
indexId);
inplace = true;
}
/* Fetch info needed for index_build */
indexInfo = BuildIndexInfo(iRel);
if (inplace)
{
/*
* Release any buffers associated with this index. If they're
* dirty, they're just dropped without bothering to flush to disk.
*/
DropRelationBuffers(iRel);
/* Now truncate the actual data and set blocks to zero */
smgrtruncate(DEFAULT_SMGR, iRel, 0);
iRel->rd_nblocks = 0;
iRel->rd_targblock = InvalidBlockNumber;
}
else
{
/*
* We'll build a new physical relation for the index.
*/
setNewRelfilenode(iRel);
}
/* Initialize the index and rebuild */
index_build(heapRelation, iRel, indexInfo);
/*
* index_build will close both the heap and index relations (but not
* give up the locks we hold on them). So we're done.
*/
SetReindexProcessing(old);
return true;
}
#ifdef NOT_USED
/*
* activate_indexes_of_a_table
* activate/deactivate indexes of the specified table.
*
* Caller must already hold exclusive lock on the table.
*/
bool
activate_indexes_of_a_table(Relation heaprel, bool activate)
{
if (IndexesAreActive(heaprel))
{
if (!activate)
setRelhasindex(RelationGetRelid(heaprel), false, false,
InvalidOid);
else
return false;
}
else
{
if (activate)
reindex_relation(RelationGetRelid(heaprel), false);
else
return false;
}
return true;
}
#endif /* NOT_USED */
/*
* reindex_relation - This routine is used to recreate all indexes
* of a relation.
*/
bool
reindex_relation(Oid relid, bool force)
{
Relation indexRelation;
ScanKeyData entry;
HeapScanDesc scan;
HeapTuple indexTuple;
bool old,
reindexed;
bool overwrite;
Relation rel;
overwrite = false;
/*
* Ensure to hold an exclusive lock throughout the transaction. The
* lock could be less intensive (in the non-overwrite path) but for
* now it's AccessExclusiveLock for simplicity.
*/
rel = heap_open(relid, AccessExclusiveLock);
/*
* Should be ignoring system indexes if we are reindexing a system table.
* (This is elog not ereport because caller should have caught it.)
*/
if (!IsIgnoringSystemIndexes() &&
IsSystemRelation(rel) && !IsToastRelation(rel))
elog(ERROR,
"must be ignoring system indexes to reindex system table %u",
relid);
/*
* Shared system indexes must be overwritten because it's impossible
* to update pg_class tuples of all databases.
*/
if (rel->rd_rel->relisshared)
{
if (!IsIgnoringSystemIndexes()) /* shouldn't happen */
elog(ERROR,
"must be ignoring system indexes to reindex shared table %u",
relid);
overwrite = true;
}
old = SetReindexProcessing(true);
/*
* Continue to hold the lock.
*/
heap_close(rel, NoLock);
/*
* Find table's indexes by looking in pg_index (not trusting indexes...)
*/
indexRelation = heap_openr(IndexRelationName, AccessShareLock);
ScanKeyEntryInitialize(&entry, 0,
Anum_pg_index_indrelid,
F_OIDEQ,
ObjectIdGetDatum(relid));
scan = heap_beginscan(indexRelation, SnapshotNow, 1, &entry);
reindexed = false;
while ((indexTuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
{
Form_pg_index index = (Form_pg_index) GETSTRUCT(indexTuple);
if (reindex_index(index->indexrelid, false, overwrite))
reindexed = true;
else
{
reindexed = false;
break;
}
}
heap_endscan(scan);
heap_close(indexRelation, AccessShareLock);
SetReindexProcessing(old);
return reindexed;
}
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