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Rearrange the implementation of index-only scans.

Browse Source 
This commit changes index-only scans so that data is read directly from the
index tuple without first generating a faux heap tuple.  The only immediate
benefit is that indexes on system columns (such as OID) can be used in
index-only scans, but this is necessary infrastructure if we are ever to
support index-only scans on expression indexes.  The executor is now ready
for that, though the planner still needs substantial work to recognize
the possibility.

To do this, Vars in index-only plan nodes have to refer to index columns
not heap columns.  I introduced a new special varno, INDEX_VAR, to mark
such Vars to avoid confusion.  (In passing, this commit renames the two
existing special varnos to OUTER_VAR and INNER_VAR.)  This allows
ruleutils.c to handle them with logic similar to what we use for subplan
reference Vars.

Since index-only scans are now fundamentally different from regular
indexscans so far as their expression subtrees are concerned, I also chose
to change them to have their own plan node type (and hence, their own
executor source file).
This commit is contained in:
Tom Lane 2011-10-11 14:20:06 -04:00
parent fa351d5a0d
commit a0185461dd
34 changed files with 1312 additions and 419 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

119
src/backend/commands/explain.c
View File

@ -79,6 +79,8 @@ static void show_instrumentation_count(const char *qlabel, int which,
PlanState *planstate, ExplainState *es);
static void show_foreignscan_info(ForeignScanState *fsstate, ExplainState *es);
static const char *explain_get_index_name(Oid indexId);
static void ExplainIndexScanDetails(Oid indexid, ScanDirection indexorderdir,
ExplainState *es);
static void ExplainScanTarget(Scan *plan, ExplainState *es);
static void ExplainModifyTarget(ModifyTable *plan, ExplainState *es);
static void ExplainTargetRel(Plan *plan, Index rti, ExplainState *es);
@ -656,10 +658,10 @@ ExplainNode(PlanState *planstate, List *ancestors,
pname = sname = "Seq Scan";
break;
case T_IndexScan:
if (((IndexScan *) plan)->indexonly)
pname = sname = "Index Only Scan";
else
pname = sname = "Index Scan";
pname = sname = "Index Scan";
break;
case T_IndexOnlyScan:
pname = sname = "Index Only Scan";
break;
case T_BitmapIndexScan:
pname = sname = "Bitmap Index Scan";
@ -793,42 +795,6 @@ ExplainNode(PlanState *planstate, List *ancestors,
switch (nodeTag(plan))
{
case T_IndexScan:
{
IndexScan *indexscan = (IndexScan *) plan;
const char *indexname =
explain_get_index_name(indexscan->indexid);
if (es->format == EXPLAIN_FORMAT_TEXT)
{
if (ScanDirectionIsBackward(indexscan->indexorderdir))
appendStringInfoString(es->str, " Backward");
appendStringInfo(es->str, " using %s", indexname);
}
else
{
const char *scandir;
switch (indexscan->indexorderdir)
{
case BackwardScanDirection:
scandir = "Backward";
break;
case NoMovementScanDirection:
scandir = "NoMovement";
break;
case ForwardScanDirection:
scandir = "Forward";
break;
default:
scandir = "???";
break;
}
ExplainPropertyText("Scan Direction", scandir, es);
ExplainPropertyText("Index Name", indexname, es);
}
}
/* FALL THRU */
case T_SeqScan:
case T_BitmapHeapScan:
case T_TidScan:
@ -840,6 +806,26 @@ ExplainNode(PlanState *planstate, List *ancestors,
case T_ForeignScan:
ExplainScanTarget((Scan *) plan, es);
break;
case T_IndexScan:
{
IndexScan *indexscan = (IndexScan *) plan;
ExplainIndexScanDetails(indexscan->indexid,
indexscan->indexorderdir,
es);
ExplainScanTarget((Scan *) indexscan, es);
}
break;
case T_IndexOnlyScan:
{
IndexOnlyScan *indexonlyscan = (IndexOnlyScan *) plan;
ExplainIndexScanDetails(indexonlyscan->indexid,
indexonlyscan->indexorderdir,
es);
ExplainScanTarget((Scan *) indexonlyscan, es);
}
break;
case T_BitmapIndexScan:
{
BitmapIndexScan *bitmapindexscan = (BitmapIndexScan *) plan;
@ -1014,6 +1000,19 @@ ExplainNode(PlanState *planstate, List *ancestors,
show_instrumentation_count("Rows Removed by Filter", 1,
planstate, es);
break;
case T_IndexOnlyScan:
show_scan_qual(((IndexOnlyScan *) plan)->indexqual,
"Index Cond", planstate, ancestors, es);
if (((IndexOnlyScan *) plan)->indexqual)
show_instrumentation_count("Rows Removed by Index Recheck", 2,
planstate, es);
show_scan_qual(((IndexOnlyScan *) plan)->indexorderby,
"Order By", planstate, ancestors, es);
show_scan_qual(plan->qual, "Filter", planstate, ancestors, es);
if (plan->qual)
show_instrumentation_count("Rows Removed by Filter", 1,
planstate, es);
break;
case T_BitmapIndexScan:
show_scan_qual(((BitmapIndexScan *) plan)->indexqualorig,
"Index Cond", planstate, ancestors, es);
@ -1626,6 +1625,45 @@ explain_get_index_name(Oid indexId)
return result;
}
/*
* Add some additional details about an IndexScan or IndexOnlyScan
*/
static void
ExplainIndexScanDetails(Oid indexid, ScanDirection indexorderdir,
ExplainState *es)
{
const char *indexname = explain_get_index_name(indexid);
if (es->format == EXPLAIN_FORMAT_TEXT)
{
if (ScanDirectionIsBackward(indexorderdir))
appendStringInfoString(es->str, " Backward");
appendStringInfo(es->str, " using %s", indexname);
}
else
{
const char *scandir;
switch (indexorderdir)
{
case BackwardScanDirection:
scandir = "Backward";
break;
case NoMovementScanDirection:
scandir = "NoMovement";
break;
case ForwardScanDirection:
scandir = "Forward";
break;
default:
scandir = "???";
break;
}
ExplainPropertyText("Scan Direction", scandir, es);
ExplainPropertyText("Index Name", indexname, es);
}
}
/*
* Show the target of a Scan node
*/
@ -1670,6 +1708,7 @@ ExplainTargetRel(Plan *plan, Index rti, ExplainState *es)
{
case T_SeqScan:
case T_IndexScan:
case T_IndexOnlyScan:
case T_BitmapHeapScan:
case T_TidScan:
case T_ForeignScan:

8
src/backend/commands/trigger.c
View File

@ -2734,9 +2734,9 @@ TriggerEnabled(EState *estate, ResultRelInfo *relinfo,
oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
tgqual = stringToNode(trigger->tgqual);
/* Change references to OLD and NEW to INNER and OUTER */
ChangeVarNodes(tgqual, PRS2_OLD_VARNO, INNER, 0);
ChangeVarNodes(tgqual, PRS2_NEW_VARNO, OUTER, 0);
/* Change references to OLD and NEW to INNER_VAR and OUTER_VAR */
ChangeVarNodes(tgqual, PRS2_OLD_VARNO, INNER_VAR, 0);
ChangeVarNodes(tgqual, PRS2_NEW_VARNO, OUTER_VAR, 0);
/* ExecQual wants implicit-AND form */
tgqual = (Node *) make_ands_implicit((Expr *) tgqual);
*predicate = (List *) ExecPrepareExpr((Expr *) tgqual, estate);
@ -2783,7 +2783,7 @@ TriggerEnabled(EState *estate, ResultRelInfo *relinfo,
/*
* Finally evaluate the expression, making the old and/or new tuples
* available as INNER/OUTER respectively.
* available as INNER_VAR/OUTER_VAR respectively.
*/
econtext->ecxt_innertuple = oldslot;
econtext->ecxt_outertuple = newslot;

3
src/backend/executor/Makefile
View File

@ -17,7 +17,8 @@ OBJS = execAmi.o execCurrent.o execGrouping.o execJunk.o execMain.o \
execUtils.o functions.o instrument.o nodeAppend.o nodeAgg.o \
nodeBitmapAnd.o nodeBitmapOr.o \
nodeBitmapHeapscan.o nodeBitmapIndexscan.o nodeHash.o \
nodeHashjoin.o nodeIndexscan.o nodeLimit.o nodeLockRows.o \
nodeHashjoin.o nodeIndexscan.o nodeIndexonlyscan.o \
nodeLimit.o nodeLockRows.o \
nodeMaterial.o nodeMergeAppend.o nodeMergejoin.o nodeModifyTable.o \
nodeNestloop.o nodeFunctionscan.o nodeRecursiveunion.o nodeResult.o \
nodeSeqscan.o nodeSetOp.o nodeSort.o nodeUnique.o \

21
src/backend/executor/execAmi.c
View File

@ -26,6 +26,7 @@
#include "executor/nodeGroup.h"
#include "executor/nodeHash.h"
#include "executor/nodeHashjoin.h"
#include "executor/nodeIndexonlyscan.h"
#include "executor/nodeIndexscan.h"
#include "executor/nodeLimit.h"
#include "executor/nodeLockRows.h"
@ -155,6 +156,10 @@ ExecReScan(PlanState *node)
ExecReScanIndexScan((IndexScanState *) node);
break;
case T_IndexOnlyScanState:
ExecReScanIndexOnlyScan((IndexOnlyScanState *) node);
break;
case T_BitmapIndexScanState:
ExecReScanBitmapIndexScan((BitmapIndexScanState *) node);
break;
@ -273,6 +278,10 @@ ExecMarkPos(PlanState *node)
ExecIndexMarkPos((IndexScanState *) node);
break;
case T_IndexOnlyScanState:
ExecIndexOnlyMarkPos((IndexOnlyScanState *) node);
break;
case T_TidScanState:
ExecTidMarkPos((TidScanState *) node);
break;
@ -326,6 +335,10 @@ ExecRestrPos(PlanState *node)
ExecIndexRestrPos((IndexScanState *) node);
break;
case T_IndexOnlyScanState:
ExecIndexOnlyRestrPos((IndexOnlyScanState *) node);
break;
case T_TidScanState:
ExecTidRestrPos((TidScanState *) node);
break;
@ -371,6 +384,7 @@ ExecSupportsMarkRestore(NodeTag plantype)
{
case T_SeqScan:
case T_IndexScan:
case T_IndexOnlyScan:
case T_TidScan:
case T_ValuesScan:
case T_Material:
@ -442,6 +456,10 @@ ExecSupportsBackwardScan(Plan *node)
return IndexSupportsBackwardScan(((IndexScan *) node)->indexid) &&
TargetListSupportsBackwardScan(node->targetlist);
case T_IndexOnlyScan:
return IndexSupportsBackwardScan(((IndexOnlyScan *) node)->indexid) &&
TargetListSupportsBackwardScan(node->targetlist);
case T_SubqueryScan:
return ExecSupportsBackwardScan(((SubqueryScan *) node)->subplan) &&
TargetListSupportsBackwardScan(node->targetlist);
@ -474,7 +492,8 @@ TargetListSupportsBackwardScan(List *targetlist)
}
/*
* An IndexScan node supports backward scan only if the index's AM does.
* An IndexScan or IndexOnlyScan node supports backward scan only if the
* index's AM does.
*/
static bool
IndexSupportsBackwardScan(Oid indexid)

1
src/backend/executor/execCurrent.c
View File

@ -262,6 +262,7 @@ search_plan_tree(PlanState *node, Oid table_oid)
*/
case T_SeqScanState:
case T_IndexScanState:
case T_IndexOnlyScanState:
case T_BitmapHeapScanState:
case T_TidScanState:
{

14
src/backend/executor/execProcnode.c
View File

@ -89,6 +89,7 @@
#include "executor/nodeGroup.h"
#include "executor/nodeHash.h"
#include "executor/nodeHashjoin.h"
#include "executor/nodeIndexonlyscan.h"
#include "executor/nodeIndexscan.h"
#include "executor/nodeLimit.h"
#include "executor/nodeLockRows.h"
@ -192,6 +193,11 @@ ExecInitNode(Plan *node, EState *estate, int eflags)
estate, eflags);
break;
case T_IndexOnlyScan:
result = (PlanState *) ExecInitIndexOnlyScan((IndexOnlyScan *) node,
estate, eflags);
break;
case T_BitmapIndexScan:
result = (PlanState *) ExecInitBitmapIndexScan((BitmapIndexScan *) node,
estate, eflags);
@ -397,6 +403,10 @@ ExecProcNode(PlanState *node)
result = ExecIndexScan((IndexScanState *) node);
break;
case T_IndexOnlyScanState:
result = ExecIndexOnlyScan((IndexOnlyScanState *) node);
break;
/* BitmapIndexScanState does not yield tuples */
case T_BitmapHeapScanState:
@ -627,6 +637,10 @@ ExecEndNode(PlanState *node)
ExecEndIndexScan((IndexScanState *) node);
break;
case T_IndexOnlyScanState:
ExecEndIndexOnlyScan((IndexOnlyScanState *) node);
break;
case T_BitmapIndexScanState:
ExecEndBitmapIndexScan((BitmapIndexScanState *) node);
break;

24
src/backend/executor/execQual.c
View File

@ -578,14 +578,16 @@ ExecEvalVar(ExprState *exprstate, ExprContext *econtext,
/* Get the input slot and attribute number we want */
switch (variable->varno)
{
case INNER: /* get the tuple from the inner node */
case INNER_VAR: /* get the tuple from the inner node */
slot = econtext->ecxt_innertuple;
break;
case OUTER: /* get the tuple from the outer node */
case OUTER_VAR: /* get the tuple from the outer node */
slot = econtext->ecxt_outertuple;
break;
/* INDEX_VAR is handled by default case */
default: /* get the tuple from the relation being
* scanned */
slot = econtext->ecxt_scantuple;
@ -761,14 +763,16 @@ ExecEvalScalarVar(ExprState *exprstate, ExprContext *econtext,
/* Get the input slot and attribute number we want */
switch (variable->varno)
{
case INNER: /* get the tuple from the inner node */
case INNER_VAR: /* get the tuple from the inner node */
slot = econtext->ecxt_innertuple;
break;
case OUTER: /* get the tuple from the outer node */
case OUTER_VAR: /* get the tuple from the outer node */
slot = econtext->ecxt_outertuple;
break;
/* INDEX_VAR is handled by default case */
default: /* get the tuple from the relation being
* scanned */
slot = econtext->ecxt_scantuple;
@ -804,14 +808,16 @@ ExecEvalWholeRowVar(ExprState *exprstate, ExprContext *econtext,
/* Get the input slot we want */
switch (variable->varno)
{
case INNER: /* get the tuple from the inner node */
case INNER_VAR: /* get the tuple from the inner node */
slot = econtext->ecxt_innertuple;
break;
case OUTER: /* get the tuple from the outer node */
case OUTER_VAR: /* get the tuple from the outer node */
slot = econtext->ecxt_outertuple;
break;
/* INDEX_VAR is handled by default case */
default: /* get the tuple from the relation being
* scanned */
slot = econtext->ecxt_scantuple;
@ -873,14 +879,16 @@ ExecEvalWholeRowSlow(ExprState *exprstate, ExprContext *econtext,
/* Get the input slot we want */
switch (variable->varno)
{
case INNER: /* get the tuple from the inner node */
case INNER_VAR: /* get the tuple from the inner node */
slot = econtext->ecxt_innertuple;
break;
case OUTER: /* get the tuple from the outer node */
case OUTER_VAR: /* get the tuple from the outer node */
slot = econtext->ecxt_outertuple;
break;
/* INDEX_VAR is handled by default case */
default: /* get the tuple from the relation being
* scanned */
slot = econtext->ecxt_scantuple;

9
src/backend/executor/execScan.c
View File

@ -246,10 +246,17 @@ void
ExecAssignScanProjectionInfo(ScanState *node)
{
Scan *scan = (Scan *) node->ps.plan;
Index varno;
/* Vars in an index-only scan's tlist should be INDEX_VAR */
if (IsA(scan, IndexOnlyScan))
varno = INDEX_VAR;
else
varno = scan->scanrelid;
if (tlist_matches_tupdesc(&node->ps,
scan->plan.targetlist,
scan->scanrelid,
varno,
node->ss_ScanTupleSlot->tts_tupleDescriptor))
node->ps.ps_ProjInfo = NULL;
else

12
src/backend/executor/execUtils.c
View File

@ -566,20 +566,22 @@ ExecBuildProjectionInfo(List *targetList,
switch (variable->varno)
{
case INNER:
case INNER_VAR:
varSlotOffsets[numSimpleVars] = offsetof(ExprContext,
ecxt_innertuple);
if (projInfo->pi_lastInnerVar < attnum)
projInfo->pi_lastInnerVar = attnum;
break;
case OUTER:
case OUTER_VAR:
varSlotOffsets[numSimpleVars] = offsetof(ExprContext,
ecxt_outertuple);
if (projInfo->pi_lastOuterVar < attnum)
projInfo->pi_lastOuterVar = attnum;
break;
/* INDEX_VAR is handled by default case */
default:
varSlotOffsets[numSimpleVars] = offsetof(ExprContext,
ecxt_scantuple);
@ -628,16 +630,18 @@ get_last_attnums(Node *node, ProjectionInfo *projInfo)
switch (variable->varno)
{
case INNER:
case INNER_VAR:
if (projInfo->pi_lastInnerVar < attnum)
projInfo->pi_lastInnerVar = attnum;
break;
case OUTER:
case OUTER_VAR:
if (projInfo->pi_lastOuterVar < attnum)
projInfo->pi_lastOuterVar = attnum;
break;
/* INDEX_VAR is handled by default case */
default:
if (projInfo->pi_lastScanVar < attnum)
projInfo->pi_lastScanVar = attnum;

4
src/backend/executor/nodeAgg.c
View File

@ -806,8 +806,8 @@ find_unaggregated_cols_walker(Node *node, Bitmapset **colnos)
{
Var *var = (Var *) node;
/* setrefs.c should have set the varno to OUTER */
Assert(var->varno == OUTER);
/* setrefs.c should have set the varno to OUTER_VAR */
Assert(var->varno == OUTER_VAR);
Assert(var->varlevelsup == 0);
*colnos = bms_add_member(*colnos, var->varattno);
return false;

1
src/backend/executor/nodeBitmapIndexscan.c
View File

@ -266,7 +266,6 @@ ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate, int eflags)
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->biss_RelationDesc,
node->scan.scanrelid,
node->indexqual,
false,
&indexstate->biss_ScanKeys,

4
src/backend/executor/nodeHash.c
View File

@ -755,8 +755,8 @@ ExecHashTableInsert(HashJoinTable hashtable,
* Compute the hash value for a tuple
*
* The tuple to be tested must be in either econtext->ecxt_outertuple or
* econtext->ecxt_innertuple. Vars in the hashkeys expressions reference
* either OUTER or INNER.
* econtext->ecxt_innertuple. Vars in the hashkeys expressions should have
* varno either OUTER_VAR or INNER_VAR.
*
* A TRUE result means the tuple's hash value has been successfully computed
* and stored at *hashvalue. A FALSE result means the tuple cannot match

542
src/backend/executor/nodeIndexonlyscan.c Normal file
View File

@ -0,0 +1,542 @@
/*-------------------------------------------------------------------------
*
* nodeIndexonlyscan.c
* Routines to support index-only scans
*
* Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/executor/nodeIndexonlyscan.c
*
*-------------------------------------------------------------------------
*/
/*
* INTERFACE ROUTINES
* ExecIndexOnlyScan scans an index
* IndexOnlyNext retrieve next tuple
* ExecInitIndexOnlyScan creates and initializes state info.
* ExecReScanIndexOnlyScan rescans the indexed relation.
* ExecEndIndexOnlyScan releases all storage.
* ExecIndexOnlyMarkPos marks scan position.
* ExecIndexOnlyRestrPos restores scan position.
*/
#include "postgres.h"
#include "access/relscan.h"
#include "access/visibilitymap.h"
#include "catalog/pg_opfamily.h"
#include "catalog/pg_type.h"
#include "executor/execdebug.h"
#include "executor/nodeIndexonlyscan.h"
#include "executor/nodeIndexscan.h"
#include "storage/bufmgr.h"
#include "utils/memutils.h"
#include "utils/rel.h"
static TupleTableSlot *IndexOnlyNext(IndexOnlyScanState *node);
static void StoreIndexTuple(TupleTableSlot *slot, IndexTuple itup,
Relation indexRel);
/* ----------------------------------------------------------------
* IndexOnlyNext
*
* Retrieve a tuple from the IndexOnlyScan node's index.
* ----------------------------------------------------------------
*/
static TupleTableSlot *
IndexOnlyNext(IndexOnlyScanState *node)
{
EState *estate;
ExprContext *econtext;
ScanDirection direction;
IndexScanDesc scandesc;
HeapTuple tuple;
TupleTableSlot *slot;
ItemPointer tid;
/*
* extract necessary information from index scan node
*/
estate = node->ss.ps.state;
direction = estate->es_direction;
/* flip direction if this is an overall backward scan */
if (ScanDirectionIsBackward(((IndexOnlyScan *) node->ss.ps.plan)->indexorderdir))
{
if (ScanDirectionIsForward(direction))
direction = BackwardScanDirection;
else if (ScanDirectionIsBackward(direction))
direction = ForwardScanDirection;
}
scandesc = node->ioss_ScanDesc;
econtext = node->ss.ps.ps_ExprContext;
slot = node->ss.ss_ScanTupleSlot;
/*
* OK, now that we have what we need, fetch the next tuple.
*/
while ((tid = index_getnext_tid(scandesc, direction)) != NULL)
{
/*
* We can skip the heap fetch if the TID references a heap page on
* which all tuples are known visible to everybody. In any case,
* we'll use the index tuple not the heap tuple as the data source.
*/
if (!visibilitymap_test(scandesc->heapRelation,
ItemPointerGetBlockNumber(tid),
&node->ioss_VMBuffer))
{
/*
* Rats, we have to visit the heap to check visibility.
*/
tuple = index_fetch_heap(scandesc);
if (tuple == NULL)
continue; /* no visible tuple, try next index entry */
/*
* Only MVCC snapshots are supported here, so there should be no
* need to keep following the HOT chain once a visible entry has
* been found. If we did want to allow that, we'd need to keep
* more state to remember not to call index_getnext_tid next time.
*/
if (scandesc->xs_continue_hot)
elog(ERROR, "non-MVCC snapshots are not supported in index-only scans");
/*
* Note: at this point we are holding a pin on the heap page, as
* recorded in scandesc->xs_cbuf. We could release that pin now,
* but it's not clear whether it's a win to do so. The next index
* entry might require a visit to the same heap page.
*/
}
/*
* Fill the scan tuple slot with data from the index.
*/
StoreIndexTuple(slot, scandesc->xs_itup, scandesc->indexRelation);
/*
* If the index was lossy, we have to recheck the index quals.
* (Currently, this can never happen, but we should support the case
* for possible future use, eg with GiST indexes.)
*/
if (scandesc->xs_recheck)
{
econtext->ecxt_scantuple = slot;
ResetExprContext(econtext);
if (!ExecQual(node->indexqual, econtext, false))
{
/* Fails recheck, so drop it and loop back for another */
InstrCountFiltered2(node, 1);
continue;
}
}
return slot;
}
/*
* if we get here it means the index scan failed so we are at the end of
* the scan..
*/
return ExecClearTuple(slot);
}
/*
* StoreIndexTuple
* Fill the slot with data from the index tuple.
*
* At some point this might be generally-useful functionality, but
* right now we don't need it elsewhere.
*/
static void
StoreIndexTuple(TupleTableSlot *slot, IndexTuple itup, Relation indexRel)
{
TupleDesc indexDesc = RelationGetDescr(indexRel);
int nindexatts = indexDesc->natts;
Datum *values = slot->tts_values;
bool *isnull = slot->tts_isnull;
int i;
/*
* Note: we must use the index relation's tupdesc in index_getattr,
* not the slot's tupdesc, because of index_descriptor_hack().
*/
Assert(slot->tts_tupleDescriptor->natts == nindexatts);
ExecClearTuple(slot);
for (i = 0; i < nindexatts; i++)
values[i] = index_getattr(itup, i + 1, indexDesc, &isnull[i]);
ExecStoreVirtualTuple(slot);
}
/*
* index_descriptor_hack -- ugly kluge to make index's tupdesc OK for slot
*
* This is necessary because, alone among btree opclasses, name_ops uses
* a storage type (cstring) different from its input type. The index
* tuple descriptor will show "cstring", which is correct, but we have to
* expose "name" as the slot datatype or ExecEvalVar will whine. If we
* ever want to have any other cases with a different storage type, we ought
* to think of a cleaner solution than this.
*/
static TupleDesc
index_descriptor_hack(Relation indexRel)
{
TupleDesc tupdesc = RelationGetDescr(indexRel);
int i;
/* copy so we can scribble on it safely */
tupdesc = CreateTupleDescCopy(tupdesc);
for (i = 0; i < tupdesc->natts; i++)
{
if (indexRel->rd_opfamily[i] == NAME_BTREE_FAM_OID &&
tupdesc->attrs[i]->atttypid == CSTRINGOID)
{
tupdesc->attrs[i]->atttypid = NAMEOID;
/*
* We set attlen to match the type OID just in case anything looks
* at it. Note that this is safe only because StoreIndexTuple
* will insert the data as a virtual tuple, and we don't expect
* anything will try to materialize the scan tuple slot.
*/
tupdesc->attrs[i]->attlen = NAMEDATALEN;
}
}
return tupdesc;
}
/*
* IndexOnlyRecheck -- access method routine to recheck a tuple in EvalPlanQual
*
* This can't really happen, since an index can't supply CTID which would
* be necessary data for any potential EvalPlanQual target relation. If it
* did happen, the EPQ code would pass us the wrong data, namely a heap
* tuple not an index tuple. So throw an error.
*/
static bool
IndexOnlyRecheck(IndexOnlyScanState *node, TupleTableSlot *slot)
{
elog(ERROR, "EvalPlanQual recheck is not supported in index-only scans");
return false; /* keep compiler quiet */
}
/* ----------------------------------------------------------------
* ExecIndexOnlyScan(node)
* ----------------------------------------------------------------
*/
TupleTableSlot *
ExecIndexOnlyScan(IndexOnlyScanState *node)
{
/*
* If we have runtime keys and they've not already been set up, do it now.
*/
if (node->ioss_NumRuntimeKeys != 0 && !node->ioss_RuntimeKeysReady)
ExecReScan((PlanState *) node);
return ExecScan(&node->ss,
(ExecScanAccessMtd) IndexOnlyNext,
(ExecScanRecheckMtd) IndexOnlyRecheck);
}
/* ----------------------------------------------------------------
* ExecReScanIndexOnlyScan(node)
*
* Recalculates the values of any scan keys whose value depends on
* information known at runtime, then rescans the indexed relation.
*
* Updating the scan key was formerly done separately in
* ExecUpdateIndexScanKeys. Integrating it into ReScan makes
* rescans of indices and relations/general streams more uniform.
* ----------------------------------------------------------------
*/
void
ExecReScanIndexOnlyScan(IndexOnlyScanState *node)
{
/*
* If we are doing runtime key calculations (ie, any of the index key
* values weren't simple Consts), compute the new key values. But first,
* reset the context so we don't leak memory as each outer tuple is
* scanned. Note this assumes that we will recalculate *all* runtime keys
* on each call.
*/
if (node->ioss_NumRuntimeKeys != 0)
{
ExprContext *econtext = node->ioss_RuntimeContext;
ResetExprContext(econtext);
ExecIndexEvalRuntimeKeys(econtext,
node->ioss_RuntimeKeys,
node->ioss_NumRuntimeKeys);
}
node->ioss_RuntimeKeysReady = true;
/* reset index scan */
index_rescan(node->ioss_ScanDesc,
node->ioss_ScanKeys, node->ioss_NumScanKeys,
node->ioss_OrderByKeys, node->ioss_NumOrderByKeys);
ExecScanReScan(&node->ss);
}
/* ----------------------------------------------------------------
* ExecEndIndexOnlyScan
* ----------------------------------------------------------------
*/
void
ExecEndIndexOnlyScan(IndexOnlyScanState *node)
{
Relation indexRelationDesc;
IndexScanDesc indexScanDesc;
Relation relation;
/*
* extract information from the node
*/
indexRelationDesc = node->ioss_RelationDesc;
indexScanDesc = node->ioss_ScanDesc;
relation = node->ss.ss_currentRelation;
/* Release VM buffer pin, if any. */
if (node->ioss_VMBuffer != InvalidBuffer)
{
ReleaseBuffer(node->ioss_VMBuffer);
node->ioss_VMBuffer = InvalidBuffer;
}
/*
* Free the exprcontext(s) ... now dead code, see ExecFreeExprContext
*/
#ifdef NOT_USED
ExecFreeExprContext(&node->ss.ps);
if (node->ioss_RuntimeContext)
FreeExprContext(node->ioss_RuntimeContext, true);
#endif
/*
* clear out tuple table slots
*/
ExecClearTuple(node->ss.ps.ps_ResultTupleSlot);
ExecClearTuple(node->ss.ss_ScanTupleSlot);
/*
* close the index relation (no-op if we didn't open it)
*/
if (indexScanDesc)
index_endscan(indexScanDesc);
if (indexRelationDesc)
index_close(indexRelationDesc, NoLock);
/*
* close the heap relation.
*/
ExecCloseScanRelation(relation);
}
/* ----------------------------------------------------------------
* ExecIndexOnlyMarkPos
* ----------------------------------------------------------------
*/
void
ExecIndexOnlyMarkPos(IndexOnlyScanState *node)
{
index_markpos(node->ioss_ScanDesc);
}
/* ----------------------------------------------------------------
* ExecIndexOnlyRestrPos
* ----------------------------------------------------------------
*/
void
ExecIndexOnlyRestrPos(IndexOnlyScanState *node)
{
index_restrpos(node->ioss_ScanDesc);
}
/* ----------------------------------------------------------------
* ExecInitIndexOnlyScan
*
* Initializes the index scan's state information, creates
* scan keys, and opens the base and index relations.
*
* Note: index scans have 2 sets of state information because
* we have to keep track of the base relation and the
* index relation.
* ----------------------------------------------------------------
*/
IndexOnlyScanState *
ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags)
{
IndexOnlyScanState *indexstate;
Relation currentRelation;
bool relistarget;
TupleDesc tupDesc;
/*
* create state structure
*/
indexstate = makeNode(IndexOnlyScanState);
indexstate->ss.ps.plan = (Plan *) node;
indexstate->ss.ps.state = estate;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &indexstate->ss.ps);
indexstate->ss.ps.ps_TupFromTlist = false;
/*
* initialize child expressions
*
* Note: we don't initialize all of the indexorderby expression, only the
* sub-parts corresponding to runtime keys (see below).
*/
indexstate->ss.ps.targetlist = (List *)
ExecInitExpr((Expr *) node->scan.plan.targetlist,
(PlanState *) indexstate);
indexstate->ss.ps.qual = (List *)
ExecInitExpr((Expr *) node->scan.plan.qual,
(PlanState *) indexstate);
indexstate->indexqual = (List *)
ExecInitExpr((Expr *) node->indexqual,
(PlanState *) indexstate);
/*
* tuple table initialization
*/
ExecInitResultTupleSlot(estate, &indexstate->ss.ps);
ExecInitScanTupleSlot(estate, &indexstate->ss);
/*
* open the base relation and acquire appropriate lock on it.
*/
currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
indexstate->ss.ss_currentRelation = currentRelation;
indexstate->ss.ss_currentScanDesc = NULL; /* no heap scan here */
/*
* Initialize result tuple type.
*/
ExecAssignResultTypeFromTL(&indexstate->ss.ps);
/*
* If we are just doing EXPLAIN (ie, aren't going to run the plan), stop
* here. This allows an index-advisor plugin to EXPLAIN a plan containing
* references to nonexistent indexes.
*/
if (eflags & EXEC_FLAG_EXPLAIN_ONLY)
return indexstate;
/*
* Open the index relation.
*
* If the parent table is one of the target relations of the query, then
* InitPlan already opened and write-locked the index, so we can avoid
* taking another lock here. Otherwise we need a normal reader's lock.
*/
relistarget = ExecRelationIsTargetRelation(estate, node->scan.scanrelid);
indexstate->ioss_RelationDesc = index_open(node->indexid,
relistarget ? NoLock : AccessShareLock);
/*
* Now we can get the scan tuple's type (which is the index's rowtype,
* not the heap's) and initialize result projection info.
*/
tupDesc = index_descriptor_hack(indexstate->ioss_RelationDesc);
ExecAssignScanType(&indexstate->ss, tupDesc);
ExecAssignScanProjectionInfo(&indexstate->ss);
/*
* Initialize index-specific scan state
*/
indexstate->ioss_RuntimeKeysReady = false;
indexstate->ioss_RuntimeKeys = NULL;
indexstate->ioss_NumRuntimeKeys = 0;
/*
* build the index scan keys from the index qualification
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->ioss_RelationDesc,
node->indexqual,
false,
&indexstate->ioss_ScanKeys,
&indexstate->ioss_NumScanKeys,
&indexstate->ioss_RuntimeKeys,
&indexstate->ioss_NumRuntimeKeys,
NULL, /* no ArrayKeys */
NULL);
/*
* any ORDER BY exprs have to be turned into scankeys in the same way
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->ioss_RelationDesc,
node->indexorderby,
true,
&indexstate->ioss_OrderByKeys,
&indexstate->ioss_NumOrderByKeys,
&indexstate->ioss_RuntimeKeys,
&indexstate->ioss_NumRuntimeKeys,
NULL, /* no ArrayKeys */
NULL);
/*
* If we have runtime keys, we need an ExprContext to evaluate them. The
* node's standard context won't do because we want to reset that context
* for every tuple. So, build another context just like the other one...
* -tgl 7/11/00
*/
if (indexstate->ioss_NumRuntimeKeys != 0)
{
ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;
ExecAssignExprContext(estate, &indexstate->ss.ps);
indexstate->ioss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
indexstate->ss.ps.ps_ExprContext = stdecontext;
}
else
{
indexstate->ioss_RuntimeContext = NULL;
}
/*
* Initialize scan descriptor.
*/
indexstate->ioss_ScanDesc = index_beginscan(currentRelation,
indexstate->ioss_RelationDesc,
estate->es_snapshot,
indexstate->ioss_NumScanKeys,
indexstate->ioss_NumOrderByKeys);
/* Set it up for index-only scan */
indexstate->ioss_ScanDesc->xs_want_itup = true;
indexstate->ioss_VMBuffer = InvalidBuffer;
/*
* If no run-time keys to calculate, go ahead and pass the scankeys to the
* index AM.
*/
if (indexstate->ioss_NumRuntimeKeys == 0)
index_rescan(indexstate->ioss_ScanDesc,
indexstate->ioss_ScanKeys,
indexstate->ioss_NumScanKeys,
indexstate->ioss_OrderByKeys,
indexstate->ioss_NumOrderByKeys);
/*
* all done.
*/
return indexstate;
}

142
src/backend/executor/nodeIndexscan.c
View File

@ -14,8 +14,8 @@
*/
/*
* INTERFACE ROUTINES
* ExecIndexScan scans a relation using indices
* ExecIndexNext using index to retrieve next tuple
* ExecIndexScan scans a relation using an index
* IndexNext retrieve next tuple using index
* ExecInitIndexScan creates and initializes state info.
* ExecReScanIndexScan rescans the indexed relation.
* ExecEndIndexScan releases all storage.
@ -26,7 +26,6 @@
#include "access/nbtree.h"
#include "access/relscan.h"
#include "access/visibilitymap.h"
#include "executor/execdebug.h"
#include "executor/nodeIndexscan.h"
#include "optimizer/clauses.h"
@ -37,7 +36,6 @@
static TupleTableSlot *IndexNext(IndexScanState *node);
static void IndexStoreHeapTuple(TupleTableSlot *slot, IndexScanDesc scandesc);
/* ----------------------------------------------------------------
@ -56,7 +54,6 @@ IndexNext(IndexScanState *node)
IndexScanDesc scandesc;
HeapTuple tuple;
TupleTableSlot *slot;
ItemPointer tid;
/*
* extract necessary information from index scan node
@ -76,67 +73,23 @@ IndexNext(IndexScanState *node)
slot = node->ss.ss_ScanTupleSlot;
/*
* OK, now that we have what we need, fetch the next TID.
* ok, now that we have what we need, fetch the next tuple.
*/
while ((tid = index_getnext_tid(scandesc, direction)) != NULL)
while ((tuple = index_getnext(scandesc, direction)) != NULL)
{
/*
* Attempt index-only scan, if possible. For this, we need to have
* gotten an index tuple from the AM, and we need the TID to reference
* a heap page on which all tuples are known visible to everybody.
* If that's the case, we don't need to visit the heap page for tuple
* visibility testing, and we don't need any column values that are
* not available from the index.
*
* Note: in the index-only path, we are still holding pin on the
* scan's xs_cbuf, ie, the previously visited heap page. It's not
* clear whether it'd be better to release that pin.
* Store the scanned tuple in the scan tuple slot of the scan state.
* Note: we pass 'false' because tuples returned by amgetnext are
* pointers onto disk pages and must not be pfree()'d.
*/
if (scandesc->xs_want_itup &&
visibilitymap_test(scandesc->heapRelation,
ItemPointerGetBlockNumber(tid),
&node->iss_VMBuffer))
{
/*
* Convert index tuple to look like a heap tuple, and store the
* results in the scan tuple slot.
*/
IndexStoreHeapTuple(slot, scandesc);
}
else
{
/* Index-only approach not possible, so fetch heap tuple. */
tuple = index_fetch_heap(scandesc);
/* Tuple might not be visible. */
if (tuple == NULL)
continue;
/*
* Only MVCC snapshots are supported here, so there should be no
* need to keep following the HOT chain once a visible entry has
* been found. If we did want to allow that, we'd need to keep
* more state to remember not to call index_getnext_tid next time.
*/
if (scandesc->xs_continue_hot)
elog(ERROR, "unsupported use of non-MVCC snapshot in executor");
/*
* Store the scanned tuple in the scan tuple slot of the scan
* state.
*
* Note: we pass 'false' because tuples returned by amgetnext are
* pointers onto disk pages and must not be pfree()'d.
*/
ExecStoreTuple(tuple, /* tuple to store */
slot, /* slot to store in */
scandesc->xs_cbuf, /* buffer containing tuple */
false); /* don't pfree */
}
ExecStoreTuple(tuple, /* tuple to store */
slot, /* slot to store in */
scandesc->xs_cbuf, /* buffer containing tuple */
false); /* don't pfree */
/*
* If the index was lossy, we have to recheck the index quals using
* the real tuple.
* the fetched tuple.
*/
if (scandesc->xs_recheck)
{
@ -160,53 +113,6 @@ IndexNext(IndexScanState *node)
return ExecClearTuple(slot);
}
/*
* IndexStoreHeapTuple
*
* When performing an index-only scan, we build a faux heap tuple
* from the index tuple. Columns not present in the index are set to
* NULL, which is OK because we know they won't be referenced.
*
* The faux tuple is built as a virtual tuple that depends on the
* scandesc's xs_itup, so that must remain valid for as long as we
* need the slot contents.
*/
static void
IndexStoreHeapTuple(TupleTableSlot *slot, IndexScanDesc scandesc)
{
Form_pg_index indexForm = scandesc->indexRelation->rd_index;
TupleDesc indexDesc = RelationGetDescr(scandesc->indexRelation);
int nindexatts = indexDesc->natts;
int nheapatts = slot->tts_tupleDescriptor->natts;
Datum *values = slot->tts_values;
bool *isnull = slot->tts_isnull;
int i;
/* We must first set the slot to empty, and mark all columns as null */
ExecClearTuple(slot);
memset(isnull, true, nheapatts * sizeof(bool));
/* Transpose index tuple into heap tuple. */
for (i = 0; i < nindexatts; i++)
{
int indexatt = indexForm->indkey.values[i];
/* Ignore expression columns, as well as system attributes */
if (indexatt <= 0)
continue;
Assert(indexatt <= nheapatts);
values[indexatt - 1] = index_getattr(scandesc->xs_itup, i + 1,
indexDesc,
&isnull[indexatt - 1]);
}
/* And now we can mark the slot as holding a virtual tuple. */
ExecStoreVirtualTuple(slot);
}
/*
* IndexRecheck -- access method routine to recheck a tuple in EvalPlanQual
*/
@ -493,13 +399,6 @@ ExecEndIndexScan(IndexScanState *node)
indexScanDesc = node->iss_ScanDesc;
relation = node->ss.ss_currentRelation;
/* Release VM buffer pin, if any. */
if (node->iss_VMBuffer != InvalidBuffer)
{
ReleaseBuffer(node->iss_VMBuffer);
node->iss_VMBuffer = InvalidBuffer;
}
/*
* Free the exprcontext(s) ... now dead code, see ExecFreeExprContext
*/
@ -659,7 +558,6 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->iss_RelationDesc,
node->scan.scanrelid,
node->indexqual,
false,
&indexstate->iss_ScanKeys,
@ -674,7 +572,6 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->iss_RelationDesc,
node->scan.scanrelid,
node->indexorderby,
true,
&indexstate->iss_OrderByKeys,
@ -712,10 +609,6 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
indexstate->iss_NumScanKeys,
indexstate->iss_NumOrderByKeys);
/* Prepare for possible index-only scan */
indexstate->iss_ScanDesc->xs_want_itup = node->indexonly;
indexstate->iss_VMBuffer = InvalidBuffer;
/*
* If no run-time keys to calculate, go ahead and pass the scankeys to the
* index AM.
@ -772,7 +665,6 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
*
* planstate: executor state node we are working for
* index: the index we are building scan keys for
* scanrelid: varno of the index's relation within current query
* quals: indexquals (or indexorderbys) expressions
* isorderby: true if processing ORDER BY exprs, false if processing quals
* *runtimeKeys: ptr to pre-existing IndexRuntimeKeyInfos, or NULL if none
@ -791,7 +683,7 @@ ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
* ScalarArrayOpExpr quals are not supported.
*/
void
ExecIndexBuildScanKeys(PlanState *planstate, Relation index, Index scanrelid,
ExecIndexBuildScanKeys(PlanState *planstate, Relation index,
List *quals, bool isorderby,
ScanKey *scanKeys, int *numScanKeys,
IndexRuntimeKeyInfo **runtimeKeys, int *numRuntimeKeys,
@ -865,7 +757,7 @@ ExecIndexBuildScanKeys(PlanState *planstate, Relation index, Index scanrelid,
Assert(leftop != NULL);
if (!(IsA(leftop, Var) &&
((Var *) leftop)->varno == scanrelid))
((Var *) leftop)->varno == INDEX_VAR))
elog(ERROR, "indexqual doesn't have key on left side");
varattno = ((Var *) leftop)->varattno;
@ -979,7 +871,7 @@ ExecIndexBuildScanKeys(PlanState *planstate, Relation index, Index scanrelid,
Assert(leftop != NULL);
if (!(IsA(leftop, Var) &&
((Var *) leftop)->varno == scanrelid))
((Var *) leftop)->varno == INDEX_VAR))
elog(ERROR, "indexqual doesn't have key on left side");
varattno = ((Var *) leftop)->varattno;
@ -1107,7 +999,7 @@ ExecIndexBuildScanKeys(PlanState *planstate, Relation index, Index scanrelid,
Assert(leftop != NULL);
if (!(IsA(leftop, Var) &&
((Var *) leftop)->varno == scanrelid))
((Var *) leftop)->varno == INDEX_VAR))
elog(ERROR, "indexqual doesn't have key on left side");
varattno = ((Var *) leftop)->varattno;
@ -1172,7 +1064,7 @@ ExecIndexBuildScanKeys(PlanState *planstate, Relation index, Index scanrelid,
Assert(leftop != NULL);
if (!(IsA(leftop, Var) &&
((Var *) leftop)->varno == scanrelid))
((Var *) leftop)->varno == INDEX_VAR))
elog(ERROR, "NullTest indexqual has wrong key");
varattno = ((Var *) leftop)->varattno;

4
src/backend/executor/nodeNestloop.c
View File

@ -147,8 +147,8 @@ ExecNestLoop(NestLoopState *node)
ParamExecData *prm;
prm = &(econtext->ecxt_param_exec_vals[paramno]);
/* Param value should be an OUTER var */
Assert(nlp->paramval->varno == OUTER);
/* Param value should be an OUTER_VAR var */
Assert(nlp->paramval->varno == OUTER_VAR);
Assert(nlp->paramval->varattno > 0);
prm->value = slot_getattr(outerTupleSlot,
nlp->paramval->varattno,

29
src/backend/nodes/copyfuncs.c
View File

@ -370,7 +370,31 @@ _copyIndexScan(IndexScan *from)
COPY_NODE_FIELD(indexorderby);
COPY_NODE_FIELD(indexorderbyorig);
COPY_SCALAR_FIELD(indexorderdir);
COPY_SCALAR_FIELD(indexonly);
return newnode;
}
/*
* _copyIndexOnlyScan
*/
static IndexOnlyScan *
_copyIndexOnlyScan(IndexOnlyScan *from)
{
IndexOnlyScan *newnode = makeNode(IndexOnlyScan);
/*
* copy node superclass fields
*/
CopyScanFields((Scan *) from, (Scan *) newnode);
/*
* copy remainder of node
*/
COPY_SCALAR_FIELD(indexid);
COPY_NODE_FIELD(indexqual);
COPY_NODE_FIELD(indexorderby);
COPY_NODE_FIELD(indextlist);
COPY_SCALAR_FIELD(indexorderdir);
return newnode;
}
@ -3871,6 +3895,9 @@ copyObject(void *from)
case T_IndexScan:
retval = _copyIndexScan(from);
break;
case T_IndexOnlyScan:
retval = _copyIndexOnlyScan(from);
break;
case T_BitmapIndexScan:
retval = _copyBitmapIndexScan(from);
break;

22
src/backend/nodes/outfuncs.c
View File

@ -447,7 +447,20 @@ _outIndexScan(StringInfo str, IndexScan *node)
WRITE_NODE_FIELD(indexorderby);
WRITE_NODE_FIELD(indexorderbyorig);
WRITE_ENUM_FIELD(indexorderdir, ScanDirection);
WRITE_BOOL_FIELD(indexonly);
}
static void
_outIndexOnlyScan(StringInfo str, IndexOnlyScan *node)
{
WRITE_NODE_TYPE("INDEXONLYSCAN");
_outScanInfo(str, (Scan *) node);
WRITE_OID_FIELD(indexid);
WRITE_NODE_FIELD(indexqual);
WRITE_NODE_FIELD(indexorderby);
WRITE_NODE_FIELD(indextlist);
WRITE_ENUM_FIELD(indexorderdir, ScanDirection);
}
static void
@ -1501,7 +1514,6 @@ _outIndexPath(StringInfo str, IndexPath *node)
WRITE_NODE_FIELD(indexorderbys);
WRITE_BOOL_FIELD(isjoininner);
WRITE_ENUM_FIELD(indexscandir, ScanDirection);
WRITE_BOOL_FIELD(indexonly);
WRITE_FLOAT_FIELD(indextotalcost, "%.2f");
WRITE_FLOAT_FIELD(indexselectivity, "%.4f");
WRITE_FLOAT_FIELD(rows, "%.0f");
@ -1752,8 +1764,9 @@ _outIndexOptInfo(StringInfo str, IndexOptInfo *node)
WRITE_FLOAT_FIELD(tuples, "%.0f");
WRITE_INT_FIELD(ncolumns);
WRITE_OID_FIELD(relam);
WRITE_NODE_FIELD(indexprs);
/* indexprs is redundant since we print indextlist */
WRITE_NODE_FIELD(indpred);
WRITE_NODE_FIELD(indextlist);
WRITE_BOOL_FIELD(predOK);
WRITE_BOOL_FIELD(unique);
WRITE_BOOL_FIELD(hypothetical);
@ -2707,6 +2720,9 @@ _outNode(StringInfo str, void *obj)
case T_IndexScan:
_outIndexScan(str, obj);
break;
case T_IndexOnlyScan:
_outIndexOnlyScan(str, obj);
break;
case T_BitmapIndexScan:
_outBitmapIndexScan(str, obj);
break;

8
src/backend/nodes/print.c
View File

@ -320,14 +320,18 @@ print_expr(Node *expr, List *rtable)
switch (var->varno)
{
case INNER:
case INNER_VAR:
relname = "INNER";
attname = "?";
break;
case OUTER:
case OUTER_VAR:
relname = "OUTER";
attname = "?";
break;
case INDEX_VAR:
relname = "INDEX";
attname = "?";
break;
default:
{
RangeTblEntry *rte;

23
src/backend/optimizer/path/indxpath.c
View File

@ -199,14 +199,15 @@ create_index_paths(PlannerInfo *root, RelOptInfo *rel)
true, NULL, SAOP_FORBID, ST_ANYSCAN);
/*
* Submit all the ones that can form plain IndexScan plans to add_path. (A
* plain IndexPath always represents a plain IndexScan plan; however some
* of the indexes might support only bitmap scans, and those we mustn't
* submit to add_path here.) Also, pick out the ones that might be useful
* as bitmap scans. For that, we must discard indexes that don't support
* bitmap scans, and we also are only interested in paths that have some
* selectivity; we should discard anything that was generated solely for
* ordering purposes.
* Submit all the ones that can form plain IndexScan plans to add_path.
* (A plain IndexPath might represent either a plain IndexScan or an
* IndexOnlyScan, but for our purposes here the distinction does not
* matter. However, some of the indexes might support only bitmap scans,
* and those we mustn't submit to add_path here.) Also, pick out the ones
* that might be useful as bitmap scans. For that, we must discard
* indexes that don't support bitmap scans, and we also are only
* interested in paths that have some selectivity; we should discard
* anything that was generated solely for ordering purposes.
*/
bitindexpaths = NIL;
foreach(l, indexpaths)
@ -1107,11 +1108,9 @@ check_index_only(RelOptInfo *rel, IndexOptInfo *index)
/*
* For the moment, we just ignore index expressions. It might be nice
* to do something with them, later. We also ignore index columns
* that are system columns (such as OID), because the virtual-tuple
* coding used by IndexStoreHeapTuple() can't deal with them.
* to do something with them, later.
*/
if (attno <= 0)
if (attno == 0)
continue;
index_attrs =

68
src/backend/optimizer/path/pathkeys.c
View File

@ -25,7 +25,6 @@
#include "optimizer/pathnode.h"
#include "optimizer/paths.h"
#include "optimizer/tlist.h"
#include "parser/parsetree.h"
#include "utils/lsyscache.h"
@ -35,8 +34,6 @@ static PathKey *make_canonical_pathkey(PlannerInfo *root,
EquivalenceClass *eclass, Oid opfamily,
int strategy, bool nulls_first);
static bool pathkey_is_redundant(PathKey *new_pathkey, List *pathkeys);
static Var *find_indexkey_var(PlannerInfo *root, RelOptInfo *rel,
AttrNumber varattno);
static bool right_merge_direction(PlannerInfo *root, PathKey *pathkey);
@ -504,21 +501,24 @@ build_index_pathkeys(PlannerInfo *root,
ScanDirection scandir)
{
List *retval = NIL;
ListCell *indexprs_item;
ListCell *lc;
int i;
if (index->sortopfamily == NULL)
return NIL; /* non-orderable index */
indexprs_item = list_head(index->indexprs);
for (i = 0; i < index->ncolumns; i++)
i = 0;
foreach(lc, index->indextlist)
{
TargetEntry *indextle = (TargetEntry *) lfirst(lc);
Expr *indexkey;
bool reverse_sort;
bool nulls_first;
int ikey;
Expr *indexkey;
PathKey *cpathkey;
/* We assume we don't need to make a copy of the tlist item */
indexkey = indextle->expr;
if (ScanDirectionIsBackward(scandir))
{
reverse_sort = !index->reverse_sort[i];
@ -530,21 +530,6 @@ build_index_pathkeys(PlannerInfo *root,
nulls_first = index->nulls_first[i];
}
ikey = index->indexkeys[i];
if (ikey != 0)
{
/* simple index column */
indexkey = (Expr *) find_indexkey_var(root, index->rel, ikey);
}
else
{
/* expression --- assume we need not copy it */
if (indexprs_item == NULL)
elog(ERROR, "wrong number of index expressions");
indexkey = (Expr *) lfirst(indexprs_item);
indexprs_item = lnext(indexprs_item);
}
/* OK, try to make a canonical pathkey for this sort key */
cpathkey = make_pathkey_from_sortinfo(root,
indexkey,
@ -568,46 +553,13 @@ build_index_pathkeys(PlannerInfo *root,
/* Add to list unless redundant */
if (!pathkey_is_redundant(cpathkey, retval))
retval = lappend(retval, cpathkey);
i++;
}
return retval;
}
/*
* Find or make a Var node for the specified attribute of the rel.
*
* We first look for the var in the rel's target list, because that's
* easy and fast. But the var might not be there (this should normally
* only happen for vars that are used in WHERE restriction clauses,
* but not in join clauses or in the SELECT target list). In that case,
* gin up a Var node the hard way.
*/
static Var *
find_indexkey_var(PlannerInfo *root, RelOptInfo *rel, AttrNumber varattno)
{
ListCell *temp;
Index relid;
Oid reloid,
vartypeid,
varcollid;
int32 type_mod;
foreach(temp, rel->reltargetlist)
{
Var *var = (Var *) lfirst(temp);
if (IsA(var, Var) &&
var->varattno == varattno)
return var;
}
relid = rel->relid;
reloid = getrelid(relid, root->parse->rtable);
get_atttypetypmodcoll(reloid, varattno, &vartypeid, &type_mod, &varcollid);
return makeVar(relid, varattno, vartypeid, type_mod, varcollid, 0);
}
/*
* convert_subquery_pathkeys
* Build a pathkeys list that describes the ordering of a subquery's

136
src/backend/optimizer/plan/createplan.c
View File

@ -53,8 +53,8 @@ static Material *create_material_plan(PlannerInfo *root, MaterialPath *best_path
static Plan *create_unique_plan(PlannerInfo *root, UniquePath *best_path);
static SeqScan *create_seqscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static IndexScan *create_indexscan_plan(PlannerInfo *root, IndexPath *best_path,
List *tlist, List *scan_clauses);
static Scan *create_indexscan_plan(PlannerInfo *root, IndexPath *best_path,
List *tlist, List *scan_clauses, bool indexonly);
static BitmapHeapScan *create_bitmap_scan_plan(PlannerInfo *root,
BitmapHeapPath *best_path,
List *tlist, List *scan_clauses);
@ -95,7 +95,12 @@ static SeqScan *make_seqscan(List *qptlist, List *qpqual, Index scanrelid);
static IndexScan *make_indexscan(List *qptlist, List *qpqual, Index scanrelid,
Oid indexid, List *indexqual, List *indexqualorig,
List *indexorderby, List *indexorderbyorig,
ScanDirection indexscandir, bool indexonly);
ScanDirection indexscandir);
static IndexOnlyScan *make_indexonlyscan(List *qptlist, List *qpqual,
Index scanrelid, Oid indexid,
List *indexqual, List *indexorderby,
List *indextlist,
ScanDirection indexscandir);
static BitmapIndexScan *make_bitmap_indexscan(Index scanrelid, Oid indexid,
List *indexqual,
List *indexqualorig);
@ -206,6 +211,7 @@ create_plan_recurse(PlannerInfo *root, Path *best_path)
{
case T_SeqScan:
case T_IndexScan:
case T_IndexOnlyScan:
case T_BitmapHeapScan:
case T_TidScan:
case T_SubqueryScan:
@ -274,10 +280,18 @@ create_scan_plan(PlannerInfo *root, Path *best_path)
*/
if (use_physical_tlist(root, rel))
{
tlist = build_physical_tlist(root, rel);
/* if fail because of dropped cols, use regular method */
if (tlist == NIL)
tlist = build_relation_tlist(rel);
if (best_path->pathtype == T_IndexOnlyScan)
{
/* For index-only scan, the preferred tlist is the index's */
tlist = copyObject(((IndexPath *) best_path)->indexinfo->indextlist);
}
else
{
tlist = build_physical_tlist(root, rel);
/* if fail because of dropped cols, use regular method */
if (tlist == NIL)
tlist = build_relation_tlist(rel);
}
}
else
tlist = build_relation_tlist(rel);
@ -302,7 +316,16 @@ create_scan_plan(PlannerInfo *root, Path *best_path)
plan = (Plan *) create_indexscan_plan(root,
(IndexPath *) best_path,
tlist,
scan_clauses);
scan_clauses,
false);
break;
case T_IndexOnlyScan:
plan = (Plan *) create_indexscan_plan(root,
(IndexPath *) best_path,
tlist,
scan_clauses,
true);
break;
case T_BitmapHeapScan:
@ -476,6 +499,7 @@ disuse_physical_tlist(Plan *plan, Path *path)
{
case T_SeqScan:
case T_IndexScan:
case T_IndexOnlyScan:
case T_BitmapHeapScan:
case T_TidScan:
case T_SubqueryScan:
@ -1044,16 +1068,23 @@ create_seqscan_plan(PlannerInfo *root, Path *best_path,
* Returns an indexscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*
* We use this for both plain IndexScans and IndexOnlyScans, because the
* qual preprocessing work is the same for both. Note that the caller tells
* us which to build --- we don't look at best_path->path.pathtype, because
* create_bitmap_subplan needs to be able to override the prior decision.
*
* The indexquals list of the path contains implicitly-ANDed qual conditions.
* The list can be empty --- then no index restrictions will be applied during
* the scan.
*/
static IndexScan *
static Scan *
create_indexscan_plan(PlannerInfo *root,
IndexPath *best_path,
List *tlist,
List *scan_clauses)
List *scan_clauses,
bool indexonly)
{
Scan *scan_plan;
List *indexquals = best_path->indexquals;
List *indexorderbys = best_path->indexorderbys;
Index baserelid = best_path->path.parent->relid;
@ -1063,7 +1094,6 @@ create_indexscan_plan(PlannerInfo *root,
List *fixed_indexquals;
List *fixed_indexorderbys;
ListCell *l;
IndexScan *scan_plan;
/* it should be a base rel... */
Assert(baserelid > 0);
@ -1077,7 +1107,7 @@ create_indexscan_plan(PlannerInfo *root,
/*
* The executor needs a copy with the indexkey on the left of each clause
* and with index attr numbers substituted for table ones.
* and with index Vars substituted for table ones.
*/
fixed_indexquals = fix_indexqual_references(root, best_path, indexquals);
@ -1175,20 +1205,29 @@ create_indexscan_plan(PlannerInfo *root,
}
/* Finally ready to build the plan node */
scan_plan = make_indexscan(tlist,
qpqual,
baserelid,
indexoid,
fixed_indexquals,
stripped_indexquals,
fixed_indexorderbys,
indexorderbys,
best_path->indexscandir,
best_path->indexonly);
if (indexonly)
scan_plan = (Scan *) make_indexonlyscan(tlist,
qpqual,
baserelid,
indexoid,
fixed_indexquals,
fixed_indexorderbys,
best_path->indexinfo->indextlist,
best_path->indexscandir);
else
scan_plan = (Scan *) make_indexscan(tlist,
qpqual,
baserelid,
indexoid,
fixed_indexquals,
stripped_indexquals,
fixed_indexorderbys,
indexorderbys,
best_path->indexscandir);
copy_path_costsize(&scan_plan->scan.plan, &best_path->path);
copy_path_costsize(&scan_plan->plan, &best_path->path);
/* use the indexscan-specific rows estimate, not the parent rel's */
scan_plan->scan.plan.plan_rows = best_path->rows;
scan_plan->plan.plan_rows = best_path->rows;
return scan_plan;
}
@ -1440,7 +1479,9 @@ create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
ListCell *l;
/* Use the regular indexscan plan build machinery... */
iscan = create_indexscan_plan(root, ipath, NIL, NIL);
iscan = (IndexScan *) create_indexscan_plan(root, ipath,
NIL, NIL, false);
Assert(IsA(iscan, IndexScan));
/* then convert to a bitmap indexscan */
plan = (Plan *) make_bitmap_indexscan(iscan->scan.scanrelid,
iscan->indexid,
@ -2549,17 +2590,13 @@ fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path,
/*
* fix_indexqual_operand
* Convert an indexqual expression to a Var referencing the index column.
*
* We represent index keys by Var nodes having varno == INDEX_VAR and varattno
* equal to the index's attribute number (index column position).
*/
static Node *
fix_indexqual_operand(Node *node, IndexOptInfo *index)
{
/*
* We represent index keys by Var nodes having the varno of the base table
* but varattno equal to the index's attribute number (index column
* position). This is a bit hokey ... would be cleaner to use a
* special-purpose node type that could not be mistaken for a regular Var.
* But it will do for now.
*/
Var *result;
int pos;
ListCell *indexpr_item;
@ -2583,6 +2620,7 @@ fix_indexqual_operand(Node *node, IndexOptInfo *index)
if (index->indexkeys[pos] == varatt)
{
result = (Var *) copyObject(node);
result->varno = INDEX_VAR;
result->varattno = pos + 1;
return (Node *) result;
}
@ -2606,7 +2644,7 @@ fix_indexqual_operand(Node *node, IndexOptInfo *index)
if (equal(node, indexkey))
{
/* Found a match */
result = makeVar(index->rel->relid, pos + 1,
result = makeVar(INDEX_VAR, pos + 1,
exprType(lfirst(indexpr_item)), -1,
exprCollation(lfirst(indexpr_item)),
0);
@ -2842,8 +2880,7 @@ make_indexscan(List *qptlist,
List *indexqualorig,
List *indexorderby,
List *indexorderbyorig,
ScanDirection indexscandir,
bool indexonly)
ScanDirection indexscandir)
{
IndexScan *node = makeNode(IndexScan);
Plan *plan = &node->scan.plan;
@ -2860,7 +2897,34 @@ make_indexscan(List *qptlist,
node->indexorderby = indexorderby;
node->indexorderbyorig = indexorderbyorig;
node->indexorderdir = indexscandir;
node->indexonly = indexonly;
return node;
}
static IndexOnlyScan *
make_indexonlyscan(List *qptlist,
List *qpqual,
Index scanrelid,
Oid indexid,
List *indexqual,
List *indexorderby,
List *indextlist,
ScanDirection indexscandir)
{
IndexOnlyScan *node = makeNode(IndexOnlyScan);
Plan *plan = &node->scan.plan;
/* cost should be inserted by caller */
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->indexid = indexid;
node->indexqual = indexqual;
node->indexorderby = indexorderby;
node->indextlist = indextlist;
node->indexorderdir = indexscandir;
return node;
}

138
src/backend/optimizer/plan/setrefs.c
View File

@ -63,6 +63,7 @@ typedef struct
{
PlannerInfo *root;
indexed_tlist *subplan_itlist;
Index newvarno;
int rtoffset;
} fix_upper_expr_context;
@ -81,6 +82,9 @@ typedef struct
((List *) fix_scan_expr(root, (Node *) (lst), rtoffset))
static Plan *set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset);
static Plan *set_indexonlyscan_references(PlannerInfo *root,
IndexOnlyScan *plan,
int rtoffset);
static Plan *set_subqueryscan_references(PlannerInfo *root,
SubqueryScan *plan,
int rtoffset);
@ -113,6 +117,7 @@ static Node *fix_join_expr_mutator(Node *node,
static Node *fix_upper_expr(PlannerInfo *root,
Node *node,
indexed_tlist *subplan_itlist,
Index newvarno,
int rtoffset);
static Node *fix_upper_expr_mutator(Node *node,
fix_upper_expr_context *context);
@ -234,6 +239,16 @@ set_plan_references(PlannerInfo *root, Plan *plan)
newrte->relid);
}
/*
* Check for RT index overflow; it's very unlikely, but if it did happen,
* the executor would get confused by varnos that match the special varno
* values.
*/
if (IS_SPECIAL_VARNO(list_length(glob->finalrtable)))
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("too many range table entries")));
/*
* Adjust RT indexes of PlanRowMarks and add to final rowmarks list
*/
@ -305,6 +320,13 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset)
fix_scan_list(root, splan->indexorderbyorig, rtoffset);
}
break;
case T_IndexOnlyScan:
{
IndexOnlyScan *splan = (IndexOnlyScan *) plan;
return set_indexonlyscan_references(root, splan, rtoffset);
}
break;
case T_BitmapIndexScan:
{
BitmapIndexScan *splan = (BitmapIndexScan *) plan;
@ -652,6 +674,49 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset)
return plan;
}
/*
* set_indexonlyscan_references
* Do set_plan_references processing on an IndexOnlyScan
*
* This is unlike the handling of a plain IndexScan because we have to
* convert Vars referencing the heap into Vars referencing the index.
* We can use the fix_upper_expr machinery for that, by working from a
* targetlist describing the index columns.
*/
static Plan *
set_indexonlyscan_references(PlannerInfo *root,
IndexOnlyScan *plan,
int rtoffset)
{
indexed_tlist *index_itlist;
index_itlist = build_tlist_index(plan->indextlist);
plan->scan.scanrelid += rtoffset;
plan->scan.plan.targetlist = (List *)
fix_upper_expr(root,
(Node *) plan->scan.plan.targetlist,
index_itlist,
INDEX_VAR,
rtoffset);
plan->scan.plan.qual = (List *)
fix_upper_expr(root,
(Node *) plan->scan.plan.qual,
index_itlist,
INDEX_VAR,
rtoffset);
/* indexqual is already transformed to reference index columns */
plan->indexqual = fix_scan_list(root, plan->indexqual, rtoffset);
/* indexorderby is already transformed to reference index columns */
plan->indexorderby = fix_scan_list(root, plan->indexorderby, rtoffset);
/* indextlist must NOT be transformed to reference index columns */
plan->indextlist = fix_scan_list(root, plan->indextlist, rtoffset);
pfree(index_itlist);
return (Plan *) plan;
}
/*
* set_subqueryscan_references
* Do set_plan_references processing on a SubqueryScan
@ -919,11 +984,13 @@ fix_scan_expr_mutator(Node *node, fix_scan_expr_context *context)
Assert(var->varlevelsup == 0);
/*
* We should not see any Vars marked INNER or OUTER.
* We should not see any Vars marked INNER_VAR or OUTER_VAR. But an
* indexqual expression could contain INDEX_VAR Vars.
*/
Assert(var->varno != INNER);
Assert(var->varno != OUTER);
var->varno += context->rtoffset;
Assert(var->varno != INNER_VAR);
Assert(var->varno != OUTER_VAR);
if (!IS_SPECIAL_VARNO(var->varno))
var->varno += context->rtoffset;
if (var->varnoold > 0)
var->varnoold += context->rtoffset;
return (Node *) var;
@ -932,9 +999,10 @@ fix_scan_expr_mutator(Node *node, fix_scan_expr_context *context)
{
CurrentOfExpr *cexpr = (CurrentOfExpr *) copyObject(node);
Assert(cexpr->cvarno != INNER);
Assert(cexpr->cvarno != OUTER);
cexpr->cvarno += context->rtoffset;
Assert(cexpr->cvarno != INNER_VAR);
Assert(cexpr->cvarno != OUTER_VAR);
if (!IS_SPECIAL_VARNO(cexpr->cvarno))
cexpr->cvarno += context->rtoffset;
return (Node *) cexpr;
}
if (IsA(node, PlaceHolderVar))
@ -963,9 +1031,9 @@ fix_scan_expr_walker(Node *node, fix_scan_expr_context *context)
/*
* set_join_references
* Modify the target list and quals of a join node to reference its
* subplans, by setting the varnos to OUTER or INNER and setting attno
* values to the result domain number of either the corresponding outer
* or inner join tuple item. Also perform opcode lookup for these
* subplans, by setting the varnos to OUTER_VAR or INNER_VAR and setting
* attno values to the result domain number of either the corresponding
* outer or inner join tuple item. Also perform opcode lookup for these
* expressions. and add regclass OIDs to root->glob->relationOids.
*/
static void
@ -1012,6 +1080,7 @@ set_join_references(PlannerInfo *root, Join *join, int rtoffset)
nlp->paramval = (Var *) fix_upper_expr(root,
(Node *) nlp->paramval,
outer_itlist,
OUTER_VAR,
rtoffset);
}
}
@ -1083,17 +1152,19 @@ set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset)
search_indexed_tlist_for_sortgroupref((Node *) tle->expr,
tle->ressortgroupref,
subplan_itlist,
OUTER);
OUTER_VAR);
if (!newexpr)
newexpr = fix_upper_expr(root,
(Node *) tle->expr,
subplan_itlist,
OUTER_VAR,
rtoffset);
}
else
newexpr = fix_upper_expr(root,
(Node *) tle->expr,
subplan_itlist,
OUTER_VAR,
rtoffset);
tle = flatCopyTargetEntry(tle);
tle->expr = (Expr *) newexpr;
@ -1105,6 +1176,7 @@ set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset)
fix_upper_expr(root,
(Node *) plan->qual,
subplan_itlist,
OUTER_VAR,
rtoffset);
pfree(subplan_itlist);
@ -1113,7 +1185,7 @@ set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset)
/*
* set_dummy_tlist_references
* Replace the targetlist of an upper-level plan node with a simple
* list of OUTER references to its child.
* list of OUTER_VAR references to its child.
*
* This is used for plan types like Sort and Append that don't evaluate
* their targetlists. Although the executor doesn't care at all what's in
@ -1136,7 +1208,7 @@ set_dummy_tlist_references(Plan *plan, int rtoffset)
Var *oldvar = (Var *) tle->expr;
Var *newvar;
newvar = makeVar(OUTER,
newvar = makeVar(OUTER_VAR,
tle->resno,
exprType((Node *) oldvar),
exprTypmod((Node *) oldvar),
@ -1382,11 +1454,12 @@ search_indexed_tlist_for_sortgroupref(Node *node,
* relation target lists. Also perform opcode lookup and add
* regclass OIDs to root->glob->relationOids.
*
* This is used in two different scenarios: a normal join clause, where
* all the Vars in the clause *must* be replaced by OUTER or INNER references;
* and a RETURNING clause, which may contain both Vars of the target relation
* and Vars of other relations. In the latter case we want to replace the
* other-relation Vars by OUTER references, while leaving target Vars alone.
* This is used in two different scenarios: a normal join clause, where all
* the Vars in the clause *must* be replaced by OUTER_VAR or INNER_VAR
* references; and a RETURNING clause, which may contain both Vars of the
* target relation and Vars of other relations. In the latter case we want
* to replace the other-relation Vars by OUTER_VAR references, while leaving
* target Vars alone.
*
* For a normal join, acceptable_rel should be zero so that any failure to
* match a Var will be reported as an error. For the RETURNING case, pass
@ -1435,7 +1508,7 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
/* First look for the var in the input tlists */
newvar = search_indexed_tlist_for_var(var,
context->outer_itlist,
OUTER,
OUTER_VAR,
context->rtoffset);
if (newvar)
return (Node *) newvar;
@ -1443,7 +1516,7 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
{
newvar = search_indexed_tlist_for_var(var,
context->inner_itlist,
INNER,
INNER_VAR,
context->rtoffset);
if (newvar)
return (Node *) newvar;
@ -1470,7 +1543,7 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
{
newvar = search_indexed_tlist_for_non_var((Node *) phv,
context->outer_itlist,
OUTER);
OUTER_VAR);
if (newvar)
return (Node *) newvar;
}
@ -1478,7 +1551,7 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
{
newvar = search_indexed_tlist_for_non_var((Node *) phv,
context->inner_itlist,
INNER);
INNER_VAR);
if (newvar)
return (Node *) newvar;
}
@ -1491,7 +1564,7 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
{
newvar = search_indexed_tlist_for_non_var(node,
context->outer_itlist,
OUTER);
OUTER_VAR);
if (newvar)
return (Node *) newvar;
}
@ -1499,7 +1572,7 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
{
newvar = search_indexed_tlist_for_non_var(node,
context->inner_itlist,
INNER);
INNER_VAR);
if (newvar)
return (Node *) newvar;
}
@ -1516,7 +1589,7 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
* root->glob->relationOids.
*
* This is used to fix up target and qual expressions of non-join upper-level
* plan nodes.
* plan nodes, as well as index-only scan nodes.
*
* An error is raised if no matching var can be found in the subplan tlist
* --- so this routine should only be applied to nodes whose subplans'
@ -1529,23 +1602,26 @@ fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
* subplan tlist is just a flattened list of Vars.)
*
* 'node': the tree to be fixed (a target item or qual)
* 'subplan_itlist': indexed target list for subplan
* 'subplan_itlist': indexed target list for subplan (or index)
* 'newvarno': varno to use for Vars referencing tlist elements
* 'rtoffset': how much to increment varnoold by
*
* The resulting tree is a copy of the original in which all Var nodes have
* varno = OUTER, varattno = resno of corresponding subplan target.
* varno = newvarno, varattno = resno of corresponding targetlist element.
* The original tree is not modified.
*/
static Node *
fix_upper_expr(PlannerInfo *root,
Node *node,
indexed_tlist *subplan_itlist,
Index newvarno,
int rtoffset)
{
fix_upper_expr_context context;
context.root = root;
context.subplan_itlist = subplan_itlist;
context.newvarno = newvarno;
context.rtoffset = rtoffset;
return fix_upper_expr_mutator(node, &context);
}
@ -1563,7 +1639,7 @@ fix_upper_expr_mutator(Node *node, fix_upper_expr_context *context)
newvar = search_indexed_tlist_for_var(var,
context->subplan_itlist,
OUTER,
context->newvarno,
context->rtoffset);
if (!newvar)
elog(ERROR, "variable not found in subplan target list");
@ -1578,7 +1654,7 @@ fix_upper_expr_mutator(Node *node, fix_upper_expr_context *context)
{
newvar = search_indexed_tlist_for_non_var((Node *) phv,
context->subplan_itlist,
OUTER);
context->newvarno);
if (newvar)
return (Node *) newvar;
}
@ -1590,7 +1666,7 @@ fix_upper_expr_mutator(Node *node, fix_upper_expr_context *context)
{
newvar = search_indexed_tlist_for_non_var(node,
context->subplan_itlist,
OUTER);
context->newvarno);
if (newvar)
return (Node *) newvar;
}
@ -1610,7 +1686,7 @@ fix_upper_expr_mutator(Node *node, fix_upper_expr_context *context)
* table should be left alone, however (the executor will evaluate them
* using the actual heap tuple, after firing triggers if any). In the
* adjusted RETURNING list, result-table Vars will still have their
* original varno, but Vars for other rels will have varno OUTER.
* original varno, but Vars for other rels will have varno OUTER_VAR.
*
* We also must perform opcode lookup and add regclass OIDs to
* root->glob->relationOids.

12
src/backend/optimizer/plan/subselect.c
View File

@ -1974,6 +1974,18 @@ finalize_plan(PlannerInfo *root, Plan *plan, Bitmapset *valid_params,
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_IndexOnlyScan:
finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexqual,
&context);
finalize_primnode((Node *) ((IndexOnlyScan *) plan)->indexorderby,
&context);
/*
* we need not look at indextlist, since it cannot contain Params.
*/
context.paramids = bms_add_members(context.paramids, scan_params);
break;
case T_BitmapIndexScan:
finalize_primnode((Node *) ((BitmapIndexScan *) plan)->indexqual,
&context);

3
src/backend/optimizer/util/pathnode.c
View File

@ -452,7 +452,7 @@ create_index_path(PlannerInfo *root,
indexscandir = NoMovementScanDirection;
}
pathnode->path.pathtype = T_IndexScan;
pathnode->path.pathtype = indexonly ? T_IndexOnlyScan : T_IndexScan;
pathnode->path.parent = rel;
pathnode->path.pathkeys = pathkeys;
@ -470,7 +470,6 @@ create_index_path(PlannerInfo *root,
pathnode->isjoininner = (outer_rel != NULL);
pathnode->indexscandir = indexscandir;
pathnode->indexonly = indexonly;
if (outer_rel != NULL)
{

71
src/backend/optimizer/util/plancat.c
View File

@ -22,6 +22,7 @@
#include "access/sysattr.h"
#include "access/transam.h"
#include "catalog/catalog.h"
#include "catalog/heap.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "optimizer/clauses.h"
@ -49,6 +50,8 @@ static int32 get_rel_data_width(Relation rel, int32 *attr_widths);
static List *get_relation_constraints(PlannerInfo *root,
Oid relationObjectId, RelOptInfo *rel,
bool include_notnull);
static List *build_index_tlist(PlannerInfo *root, IndexOptInfo *index,
Relation heapRelation);
/*
@ -314,6 +317,10 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
ChangeVarNodes((Node *) info->indexprs, 1, varno, 0);
if (info->indpred && varno != 1)
ChangeVarNodes((Node *) info->indpred, 1, varno, 0);
/* Build targetlist using the completed indexprs data */
info->indextlist = build_index_tlist(root, info, relation);
info->predOK = false; /* set later in indxpath.c */
info->unique = index->indisunique;
info->hypothetical = false;
@ -900,6 +907,70 @@ build_physical_tlist(PlannerInfo *root, RelOptInfo *rel)
return tlist;
}
/*
* build_index_tlist
*
* Build a targetlist representing the columns of the specified index.
* Each column is represented by a Var for the corresponding base-relation
* column, or an expression in base-relation Vars, as appropriate.
*
* There are never any dropped columns in indexes, so unlike
* build_physical_tlist, we need no failure case.
*/
static List *
build_index_tlist(PlannerInfo *root, IndexOptInfo *index,
Relation heapRelation)
{
List *tlist = NIL;
Index varno = index->rel->relid;
ListCell *indexpr_item;
int i;
indexpr_item = list_head(index->indexprs);
for (i = 0; i < index->ncolumns; i++)
{
int indexkey = index->indexkeys[i];
Expr *indexvar;
if (indexkey != 0)
{
/* simple column */
Form_pg_attribute att_tup;
if (indexkey < 0)
att_tup = SystemAttributeDefinition(indexkey,
heapRelation->rd_rel->relhasoids);
else
att_tup = heapRelation->rd_att->attrs[indexkey - 1];
indexvar = (Expr *) makeVar(varno,
indexkey,
att_tup->atttypid,
att_tup->atttypmod,
att_tup->attcollation,
0);
}
else
{
/* expression column */
if (indexpr_item == NULL)
elog(ERROR, "wrong number of index expressions");
indexvar = (Expr *) lfirst(indexpr_item);
indexpr_item = lnext(indexpr_item);
}
tlist = lappend(tlist,
makeTargetEntry(indexvar,
i + 1,
NULL,
false));
}
if (indexpr_item != NULL)
elog(ERROR, "wrong number of index expressions");
return tlist;
}
/*
* restriction_selectivity
*

159
src/backend/utils/adt/ruleutils.c
View File

@ -107,9 +107,11 @@ typedef struct
* deparse_namespace list (since a plan tree never contains Vars with
* varlevelsup > 0). We store the PlanState node that is the immediate
* parent of the expression to be deparsed, as well as a list of that
* PlanState's ancestors. In addition, we store the outer and inner
* subplan nodes, whose targetlists are used to resolve OUTER and INNER Vars.
* (Note: these could be derived on-the-fly from the planstate instead.)
* PlanState's ancestors. In addition, we store its outer and inner subplan
* state nodes, as well as their plan nodes' targetlists, and the indextlist
* if the current PlanState is an IndexOnlyScanState. (These fields could
* be derived on-the-fly from the current PlanState, but it seems notationally
* clearer to set them up as separate fields.)
*/
typedef struct
{
@ -118,10 +120,11 @@ typedef struct
/* Remaining fields are used only when deparsing a Plan tree: */
PlanState *planstate; /* immediate parent of current expression */
List *ancestors; /* ancestors of planstate */
PlanState *outer_planstate; /* OUTER subplan state, or NULL if none */
PlanState *inner_planstate; /* INNER subplan state, or NULL if none */
Plan *outer_plan; /* OUTER subplan, or NULL if none */
Plan *inner_plan; /* INNER subplan, or NULL if none */
PlanState *outer_planstate; /* outer subplan state, or NULL if none */
PlanState *inner_planstate; /* inner subplan state, or NULL if none */
List *outer_tlist; /* referent for OUTER_VAR Vars */
List *inner_tlist; /* referent for INNER_VAR Vars */
List *index_tlist; /* referent for INDEX_VAR Vars */
} deparse_namespace;
@ -2162,9 +2165,14 @@ deparse_context_for(const char *aliasname, Oid relid)
* deparse_context_for_planstate - Build deparse context for a plan
*
* When deparsing an expression in a Plan tree, we might have to resolve
* OUTER or INNER references. To do this, the caller must provide the
* parent PlanState node. Then OUTER and INNER references can be resolved
* by drilling down into the left and right child plans.
* OUTER_VAR, INNER_VAR, or INDEX_VAR references. To do this, the caller must
* provide the parent PlanState node. Then OUTER_VAR and INNER_VAR references
* can be resolved by drilling down into the left and right child plans.
* Similarly, INDEX_VAR references can be resolved by reference to the
* indextlist given in the parent IndexOnlyScan node. (Note that we don't
* currently support deparsing of indexquals in regular IndexScan or
* BitmapIndexScan nodes; for those, we can only deparse the indexqualorig
* fields, which won't contain INDEX_VAR Vars.)
*
* Note: planstate really ought to be declared as "PlanState *", but we use
* "Node *" to avoid having to include execnodes.h in builtins.h.
@ -2175,7 +2183,7 @@ deparse_context_for(const char *aliasname, Oid relid)
*
* The plan's rangetable list must also be passed. We actually prefer to use
* the rangetable to resolve simple Vars, but the plan inputs are necessary
* for Vars that reference expressions computed in subplan target lists.
* for Vars with special varnos.
*/
List *
deparse_context_for_planstate(Node *planstate, List *ancestors,
@ -2201,10 +2209,11 @@ deparse_context_for_planstate(Node *planstate, List *ancestors,
* set_deparse_planstate: set up deparse_namespace to parse subexpressions
* of a given PlanState node
*
* This sets the planstate, outer_planstate, inner_planstate, outer_plan, and
* inner_plan fields. Caller is responsible for adjusting the ancestors list
* if necessary. Note that the rtable and ctes fields do not need to change
* when shifting attention to different plan nodes in a single plan tree.
* This sets the planstate, outer_planstate, inner_planstate, outer_tlist,
* inner_tlist, and index_tlist fields. Caller is responsible for adjusting
* the ancestors list if necessary. Note that the rtable and ctes fields do
* not need to change when shifting attention to different plan nodes in a
* single plan tree.
*/
static void
set_deparse_planstate(deparse_namespace *dpns, PlanState *ps)
@ -2229,9 +2238,9 @@ set_deparse_planstate(deparse_namespace *dpns, PlanState *ps)
dpns->outer_planstate = outerPlanState(ps);
if (dpns->outer_planstate)
dpns->outer_plan = dpns->outer_planstate->plan;
dpns->outer_tlist = dpns->outer_planstate->plan->targetlist;
else
dpns->outer_plan = NULL;
dpns->outer_tlist = NIL;
/*
* For a SubqueryScan, pretend the subplan is INNER referent. (We don't
@ -2246,18 +2255,25 @@ set_deparse_planstate(deparse_namespace *dpns, PlanState *ps)
dpns->inner_planstate = innerPlanState(ps);
if (dpns->inner_planstate)
dpns->inner_plan = dpns->inner_planstate->plan;
dpns->inner_tlist = dpns->inner_planstate->plan->targetlist;
else
dpns->inner_plan = NULL;
dpns->inner_tlist = NIL;
/* index_tlist is set only if it's an IndexOnlyScan */
if (IsA(ps->plan, IndexOnlyScan))
dpns->index_tlist = ((IndexOnlyScan *) ps->plan)->indextlist;
else
dpns->index_tlist = NIL;
}
/*
* push_child_plan: temporarily transfer deparsing attention to a child plan
*
* When expanding an OUTER or INNER reference, we must adjust the deparse
* context in case the referenced expression itself uses OUTER/INNER. We
* modify the top stack entry in-place to avoid affecting levelsup issues
* (although in a Plan tree there really shouldn't be any).
* When expanding an OUTER_VAR or INNER_VAR reference, we must adjust the
* deparse context in case the referenced expression itself uses
* OUTER_VAR/INNER_VAR. We modify the top stack entry in-place to avoid
* affecting levelsup issues (although in a Plan tree there really shouldn't
* be any).
*
* Caller must provide a local deparse_namespace variable to save the
* previous state for pop_child_plan.
@ -2271,10 +2287,11 @@ push_child_plan(deparse_namespace *dpns, PlanState *ps,
/*
* Currently we don't bother to adjust the ancestors list, because an
* OUTER or INNER reference really shouldn't contain any Params that would
* be set by the parent node itself. If we did want to adjust it,
* lcons'ing dpns->planstate onto dpns->ancestors would be the appropriate
* thing --- and pop_child_plan would need to undo the change to the list.
* OUTER_VAR or INNER_VAR reference really shouldn't contain any Params
* that would be set by the parent node itself. If we did want to adjust
* the list, lcons'ing dpns->planstate onto dpns->ancestors would be the
* appropriate thing --- and pop_child_plan would need to undo the change
* to the list.
*/
/* Set attention on selected child */
@ -2298,7 +2315,7 @@ pop_child_plan(deparse_namespace *dpns, deparse_namespace *save_dpns)
* When expanding a Param reference, we must adjust the deparse context
* to match the plan node that contains the expression being printed;
* otherwise we'd fail if that expression itself contains a Param or
* OUTER/INNER variables.
* OUTER_VAR/INNER_VAR/INDEX_VAR variable.
*
* The target ancestor is conveniently identified by the ListCell holding it
* in dpns->ancestors.
@ -3716,22 +3733,22 @@ get_variable(Var *var, int levelsup, bool showstar, deparse_context *context)
/*
* Try to find the relevant RTE in this rtable. In a plan tree, it's
* likely that varno is OUTER or INNER, in which case we must dig down
* into the subplans.
* likely that varno is OUTER_VAR or INNER_VAR, in which case we must dig
* down into the subplans, or INDEX_VAR, which is resolved similarly.
*/
if (var->varno >= 1 && var->varno <= list_length(dpns->rtable))
{
rte = rt_fetch(var->varno, dpns->rtable);
attnum = var->varattno;
}
else if (var->varno == OUTER && dpns->outer_plan)
else if (var->varno == OUTER_VAR && dpns->outer_tlist)
{
TargetEntry *tle;
deparse_namespace save_dpns;
tle = get_tle_by_resno(dpns->outer_plan->targetlist, var->varattno);
tle = get_tle_by_resno(dpns->outer_tlist, var->varattno);
if (!tle)
elog(ERROR, "bogus varattno for OUTER var: %d", var->varattno);
elog(ERROR, "bogus varattno for OUTER_VAR var: %d", var->varattno);
Assert(netlevelsup == 0);
push_child_plan(dpns, dpns->outer_planstate, &save_dpns);
@ -3749,14 +3766,14 @@ get_variable(Var *var, int levelsup, bool showstar, deparse_context *context)
pop_child_plan(dpns, &save_dpns);
return NULL;
}
else if (var->varno == INNER && dpns->inner_plan)
else if (var->varno == INNER_VAR && dpns->inner_tlist)
{
TargetEntry *tle;
deparse_namespace save_dpns;
tle = get_tle_by_resno(dpns->inner_plan->targetlist, var->varattno);
tle = get_tle_by_resno(dpns->inner_tlist, var->varattno);
if (!tle)
elog(ERROR, "bogus varattno for INNER var: %d", var->varattno);
elog(ERROR, "bogus varattno for INNER_VAR var: %d", var->varattno);
Assert(netlevelsup == 0);
push_child_plan(dpns, dpns->inner_planstate, &save_dpns);
@ -3774,6 +3791,28 @@ get_variable(Var *var, int levelsup, bool showstar, deparse_context *context)
pop_child_plan(dpns, &save_dpns);
return NULL;
}
else if (var->varno == INDEX_VAR && dpns->index_tlist)
{
TargetEntry *tle;
tle = get_tle_by_resno(dpns->index_tlist, var->varattno);
if (!tle)
elog(ERROR, "bogus varattno for INDEX_VAR var: %d", var->varattno);
Assert(netlevelsup == 0);
/*
* Force parentheses because our caller probably assumed a Var is a
* simple expression.
*/
if (!IsA(tle->expr, Var))
appendStringInfoChar(buf, '(');
get_rule_expr((Node *) tle->expr, context, true);
if (!IsA(tle->expr, Var))
appendStringInfoChar(buf, ')');
return NULL;
}
else
{
elog(ERROR, "bogus varno: %d", var->varno);
@ -3789,16 +3828,16 @@ get_variable(Var *var, int levelsup, bool showstar, deparse_context *context)
* no alias. So in that case, drill down to the subplan and print the
* contents of the referenced tlist item. This works because in a plan
* tree, such Vars can only occur in a SubqueryScan or CteScan node, and
* we'll have set dpns->inner_plan to reference the child plan node.
* we'll have set dpns->inner_planstate to reference the child plan node.
*/
if ((rte->rtekind == RTE_SUBQUERY || rte->rtekind == RTE_CTE) &&
attnum > list_length(rte->eref->colnames) &&
dpns->inner_plan)
dpns->inner_planstate)
{
TargetEntry *tle;
deparse_namespace save_dpns;
tle = get_tle_by_resno(dpns->inner_plan->targetlist, var->varattno);
tle = get_tle_by_resno(dpns->inner_tlist, var->varattno);
if (!tle)
elog(ERROR, "bogus varattno for subquery var: %d", var->varattno);
@ -3984,23 +4023,23 @@ get_name_for_var_field(Var *var, int fieldno,
/*
* Try to find the relevant RTE in this rtable. In a plan tree, it's
* likely that varno is OUTER or INNER, in which case we must dig down
* into the subplans.
* likely that varno is OUTER_VAR or INNER_VAR, in which case we must dig
* down into the subplans, or INDEX_VAR, which is resolved similarly.
*/
if (var->varno >= 1 && var->varno <= list_length(dpns->rtable))
{
rte = rt_fetch(var->varno, dpns->rtable);
attnum = var->varattno;
}
else if (var->varno == OUTER && dpns->outer_plan)
else if (var->varno == OUTER_VAR && dpns->outer_tlist)
{
TargetEntry *tle;
deparse_namespace save_dpns;
const char *result;
tle = get_tle_by_resno(dpns->outer_plan->targetlist, var->varattno);
tle = get_tle_by_resno(dpns->outer_tlist, var->varattno);
if (!tle)
elog(ERROR, "bogus varattno for OUTER var: %d", var->varattno);
elog(ERROR, "bogus varattno for OUTER_VAR var: %d", var->varattno);
Assert(netlevelsup == 0);
push_child_plan(dpns, dpns->outer_planstate, &save_dpns);
@ -4011,15 +4050,15 @@ get_name_for_var_field(Var *var, int fieldno,
pop_child_plan(dpns, &save_dpns);
return result;
}
else if (var->varno == INNER && dpns->inner_plan)
else if (var->varno == INNER_VAR && dpns->inner_tlist)
{
TargetEntry *tle;
deparse_namespace save_dpns;
const char *result;
tle = get_tle_by_resno(dpns->inner_plan->targetlist, var->varattno);
tle = get_tle_by_resno(dpns->inner_tlist, var->varattno);
if (!tle)
elog(ERROR, "bogus varattno for INNER var: %d", var->varattno);
elog(ERROR, "bogus varattno for INNER_VAR var: %d", var->varattno);
Assert(netlevelsup == 0);
push_child_plan(dpns, dpns->inner_planstate, &save_dpns);
@ -4030,6 +4069,22 @@ get_name_for_var_field(Var *var, int fieldno,
pop_child_plan(dpns, &save_dpns);
return result;
}
else if (var->varno == INDEX_VAR && dpns->index_tlist)
{
TargetEntry *tle;
const char *result;
tle = get_tle_by_resno(dpns->index_tlist, var->varattno);
if (!tle)
elog(ERROR, "bogus varattno for INDEX_VAR var: %d", var->varattno);
Assert(netlevelsup == 0);
result = get_name_for_var_field((Var *) tle->expr, fieldno,
levelsup, context);
return result;
}
else
{
elog(ERROR, "bogus varno: %d", var->varno);
@ -4115,11 +4170,10 @@ get_name_for_var_field(Var *var, int fieldno,
deparse_namespace save_dpns;
const char *result;
if (!dpns->inner_plan)
if (!dpns->inner_planstate)
elog(ERROR, "failed to find plan for subquery %s",
rte->eref->aliasname);
tle = get_tle_by_resno(dpns->inner_plan->targetlist,
attnum);
tle = get_tle_by_resno(dpns->inner_tlist, attnum);
if (!tle)
elog(ERROR, "bogus varattno for subquery var: %d",
attnum);
@ -4232,11 +4286,10 @@ get_name_for_var_field(Var *var, int fieldno,
deparse_namespace save_dpns;
const char *result;
if (!dpns->inner_plan)
if (!dpns->inner_planstate)
elog(ERROR, "failed to find plan for CTE %s",
rte->eref->aliasname);
tle = get_tle_by_resno(dpns->inner_plan->targetlist,
attnum);
tle = get_tle_by_resno(dpns->inner_tlist, attnum);
if (!tle)
elog(ERROR, "bogus varattno for subquery var: %d",
attnum);

2
src/backend/utils/adt/tid.c
View File

@ -306,7 +306,7 @@ currtid_for_view(Relation viewrel, ItemPointer tid)
Var *var = (Var *) tle->expr;
RangeTblEntry *rte;
if (var->varno > 0 && var->varno < INNER &&
if (!IS_SPECIAL_VARNO(var->varno) &&
var->varattno == SelfItemPointerAttributeNumber)
{
rte = rt_fetch(var->varno, query->rtable);

26
src/include/executor/nodeIndexonlyscan.h Normal file
View File

@ -0,0 +1,26 @@
/*-------------------------------------------------------------------------
*
* nodeIndexonlyscan.h
*
*
*
* Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/executor/nodeIndexonlyscan.h
*
*-------------------------------------------------------------------------
*/
#ifndef NODEINDEXONLYSCAN_H
#define NODEINDEXONLYSCAN_H
#include "nodes/execnodes.h"
extern IndexOnlyScanState *ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags);
extern TupleTableSlot *ExecIndexOnlyScan(IndexOnlyScanState *node);
extern void ExecEndIndexOnlyScan(IndexOnlyScanState *node);
extern void ExecIndexOnlyMarkPos(IndexOnlyScanState *node);
extern void ExecIndexOnlyRestrPos(IndexOnlyScanState *node);
extern void ExecReScanIndexOnlyScan(IndexOnlyScanState *node);
#endif /* NODEINDEXONLYSCAN_H */

7
src/include/executor/nodeIndexscan.h
View File

@ -23,9 +23,12 @@ extern void ExecIndexMarkPos(IndexScanState *node);
extern void ExecIndexRestrPos(IndexScanState *node);
extern void ExecReScanIndexScan(IndexScanState *node);
/* routines exported to share code with nodeBitmapIndexscan.c */
/*
* These routines are exported to share code with nodeIndexonlyscan.c and
* nodeBitmapIndexscan.c
*/
extern void ExecIndexBuildScanKeys(PlanState *planstate, Relation index,
Index scanrelid, List *quals, bool isorderby,
List *quals, bool isorderby,
ScanKey *scanKeys, int *numScanKeys,
IndexRuntimeKeyInfo **runtimeKeys, int *numRuntimeKeys,
IndexArrayKeyInfo **arrayKeys, int *numArrayKeys);

36
src/include/nodes/execnodes.h
View File

@ -1226,7 +1226,6 @@ typedef struct
* RuntimeContext expr context for evaling runtime Skeys
* RelationDesc index relation descriptor
* ScanDesc index scan descriptor
* VMBuffer buffer in use for visibility map testing, if any
* ----------------
*/
typedef struct IndexScanState
@ -1243,9 +1242,42 @@ typedef struct IndexScanState
ExprContext *iss_RuntimeContext;
Relation iss_RelationDesc;
IndexScanDesc iss_ScanDesc;
Buffer iss_VMBuffer;
} IndexScanState;
/* ----------------
* IndexOnlyScanState information
*
* indexqual execution state for indexqual expressions
* ScanKeys Skey structures for index quals
* NumScanKeys number of ScanKeys
* OrderByKeys Skey structures for index ordering operators
* NumOrderByKeys number of OrderByKeys
* RuntimeKeys info about Skeys that must be evaluated at runtime
* NumRuntimeKeys number of RuntimeKeys
* RuntimeKeysReady true if runtime Skeys have been computed
* RuntimeContext expr context for evaling runtime Skeys
* RelationDesc index relation descriptor
* ScanDesc index scan descriptor
* VMBuffer buffer in use for visibility map testing, if any
* ----------------
*/
typedef struct IndexOnlyScanState
{
ScanState ss; /* its first field is NodeTag */
List *indexqual;
ScanKey ioss_ScanKeys;
int ioss_NumScanKeys;
ScanKey ioss_OrderByKeys;
int ioss_NumOrderByKeys;
IndexRuntimeKeyInfo *ioss_RuntimeKeys;
int ioss_NumRuntimeKeys;
bool ioss_RuntimeKeysReady;
ExprContext *ioss_RuntimeContext;
Relation ioss_RelationDesc;
IndexScanDesc ioss_ScanDesc;
Buffer ioss_VMBuffer;
} IndexOnlyScanState;
/* ----------------
* BitmapIndexScanState information
*

2
src/include/nodes/nodes.h
View File

@ -52,6 +52,7 @@ typedef enum NodeTag
T_Scan,
T_SeqScan,
T_IndexScan,
T_IndexOnlyScan,
T_BitmapIndexScan,
T_BitmapHeapScan,
T_TidScan,
@ -97,6 +98,7 @@ typedef enum NodeTag
T_ScanState,
T_SeqScanState,
T_IndexScanState,
T_IndexOnlyScanState,
T_BitmapIndexScanState,
T_BitmapHeapScanState,
T_TidScanState,

38
src/include/nodes/plannodes.h
View File

@ -285,11 +285,8 @@ typedef Scan SeqScan;
*
* indexqual has the same form, but the expressions have been commuted if
* necessary to put the indexkeys on the left, and the indexkeys are replaced
* by Var nodes identifying the index columns (varattno is the index column
* position, not the base table's column, even though varno is for the base
* table). This is a bit hokey ... would be cleaner to use a special-purpose
* node type that could not be mistaken for a regular Var. But it will do
* for now.
* by Var nodes identifying the index columns (their varno is INDEX_VAR and
* their varattno is the index column number).
*
* indexorderbyorig is similarly the original form of any ORDER BY expressions
* that are being implemented by the index, while indexorderby is modified to
@ -302,8 +299,7 @@ typedef Scan SeqScan;
* (Note these fields are used for amcanorderbyop cases, not amcanorder cases.)
*
* indexorderdir specifies the scan ordering, for indexscans on amcanorder
* indexes (for other indexes it should be "don't care"). indexonly specifies
* an index-only scan, for indexscans on amcanreturn indexes.
* indexes (for other indexes it should be "don't care").
* ----------------
*/
typedef struct IndexScan
@ -315,9 +311,35 @@ typedef struct IndexScan
List *indexorderby; /* list of index ORDER BY exprs */
List *indexorderbyorig; /* the same in original form */
ScanDirection indexorderdir; /* forward or backward or don't care */
bool indexonly; /* attempt to skip heap fetches? */
} IndexScan;
/* ----------------
* index-only scan node
*
* IndexOnlyScan is very similar to IndexScan, but it specifies an
* index-only scan, in which the data comes from the index not the heap.
* Because of this, *all* Vars in the plan node's targetlist, qual, and
* index expressions reference index columns and have varno = INDEX_VAR.
* Hence we do not need separate indexqualorig and indexorderbyorig lists,
* since their contents would be equivalent to indexqual and indexorderby.
*
* To help EXPLAIN interpret the index Vars for display, we provide
* indextlist, which represents the contents of the index as a targetlist
* with one TLE per index column. Vars appearing in this list reference
* the base table, and this is the only field in the plan node that may
* contain such Vars.
* ----------------
*/
typedef struct IndexOnlyScan
{
Scan scan;
Oid indexid; /* OID of index to scan */
List *indexqual; /* list of index quals (usually OpExprs) */
List *indexorderby; /* list of index ORDER BY exprs */
List *indextlist; /* TargetEntry list describing index's cols */
ScanDirection indexorderdir; /* forward or backward or don't care */
} IndexOnlyScan;
/* ----------------
* bitmap index scan node
*

16
src/include/nodes/primnodes.h
View File

@ -118,15 +118,19 @@ typedef struct Expr
* Note: during parsing/planning, varnoold/varoattno are always just copies
* of varno/varattno. At the tail end of planning, Var nodes appearing in
* upper-level plan nodes are reassigned to point to the outputs of their
* subplans; for example, in a join node varno becomes INNER or OUTER and
* varattno becomes the index of the proper element of that subplan's target
* list. But varnoold/varoattno continue to hold the original values.
* subplans; for example, in a join node varno becomes INNER_VAR or OUTER_VAR
* and varattno becomes the index of the proper element of that subplan's
* target list. But varnoold/varoattno continue to hold the original values.
* The code doesn't really need varnoold/varoattno, but they are very useful
* for debugging and interpreting completed plans, so we keep them around.
*/
#define INNER 65000
#define OUTER 65001
#define INNER_VAR 65000 /* reference to inner subplan */
#define OUTER_VAR 65001 /* reference to outer subplan */
#define INDEX_VAR 65002 /* reference to index column */
#define IS_SPECIAL_VARNO(varno) ((varno) >= INNER_VAR)
/* Symbols for the indexes of the special RTE entries in rules */
#define PRS2_OLD_VARNO 1
#define PRS2_NEW_VARNO 2
@ -134,7 +138,7 @@ typedef struct Var
{
Expr xpr;
Index varno; /* index of this var's relation in the range
* table (could also be INNER or OUTER) */
* table, or INNER_VAR/OUTER_VAR/INDEX_VAR */
AttrNumber varattno; /* attribute number of this var, or zero for
* all */
Oid vartype; /* pg_type OID for the type of this var */

27
src/include/nodes/relation.h
View File

@ -449,6 +449,10 @@ typedef struct RelOptInfo
* The indexprs and indpred expressions have been run through
* prepqual.c and eval_const_expressions() for ease of matching to
* WHERE clauses. indpred is in implicit-AND form.
*
* indextlist is a TargetEntry list representing the index columns.
* It provides an equivalent base-relation Var for each simple column,
* and links to the matching indexprs element for each expression column.
*/
typedef struct IndexOptInfo
{
@ -478,6 +482,8 @@ typedef struct IndexOptInfo
List *indexprs; /* expressions for non-simple index columns */
List *indpred; /* predicate if a partial index, else NIL */
List *indextlist; /* targetlist representing index columns */
bool predOK; /* true if predicate matches query */
bool unique; /* true if a unique index */
bool hypothetical; /* true if index doesn't really exist */
@ -640,6 +646,9 @@ typedef struct Path
/*----------
* IndexPath represents an index scan over a single index.
*
* This struct is used for both regular indexscans and index-only scans;
* path.pathtype is T_IndexScan or T_IndexOnlyScan to show which is meant.
*
* 'indexinfo' is the index to be scanned.
*
* 'indexclauses' is a list of index qualification clauses, with implicit
@ -673,14 +682,10 @@ typedef struct Path
* NoMovementScanDirection for an indexscan, but the planner wants to
* distinguish ordered from unordered indexes for building pathkeys.)
*
* 'indexonly' is TRUE for an index-only scan, that is, the index's access
* method has amcanreturn = TRUE and we only need columns available from the
* index.
*
* 'indextotalcost' and 'indexselectivity' are saved in the IndexPath so that
* we need not recompute them when considering using the same index in a
* bitmap index/heap scan (see BitmapHeapPath). The costs of the IndexPath
* itself represent the costs of an IndexScan plan type.
* itself represent the costs of an IndexScan or IndexOnlyScan plan type.
*
* 'rows' is the estimated result tuple count for the indexscan. This
* is the same as path.parent->rows for a simple indexscan, but it is
@ -698,7 +703,6 @@ typedef struct IndexPath
List *indexorderbys;
bool isjoininner;
ScanDirection indexscandir;
bool indexonly;
Cost indextotalcost;
Selectivity indexselectivity;
double rows; /* estimated number of result tuples */
@ -714,11 +718,12 @@ typedef struct IndexPath
* The individual indexscans are represented by IndexPath nodes, and any
* logic on top of them is represented by a tree of BitmapAndPath and
* BitmapOrPath nodes. Notice that we can use the same IndexPath node both
* to represent a regular IndexScan plan, and as the child of a BitmapHeapPath
* that represents scanning the same index using a BitmapIndexScan. The
* startup_cost and total_cost figures of an IndexPath always represent the
* costs to use it as a regular IndexScan. The costs of a BitmapIndexScan
* can be computed using the IndexPath's indextotalcost and indexselectivity.
* to represent a regular (or index-only) index scan plan, and as the child
* of a BitmapHeapPath that represents scanning the same index using a
* BitmapIndexScan. The startup_cost and total_cost figures of an IndexPath
* always represent the costs to use it as a regular (or index-only)
* IndexScan. The costs of a BitmapIndexScan can be computed using the
* IndexPath's indextotalcost and indexselectivity.
*
* BitmapHeapPaths can be nestloop inner indexscans. The isjoininner and
* rows fields serve the same purpose as for plain IndexPaths.