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Allow row comparisons to be used as indexscan qualifications.

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This completes the project to upgrade our handling of row comparisons.
This commit is contained in:
Tom Lane 2006-01-25 20:29:24 +00:00
parent 06d45e485d
commit 3a0a16cb7e
11 changed files with 996 additions and 142 deletions
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117
src/backend/access/nbtree/nbtsearch.c
View File

@ -8,7 +8,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.101 2006/01/23 22:31:40 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.102 2006/01/25 20:29:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -551,6 +551,10 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
* one we use --- by definition, they are either redundant or
* contradictory.
*
* In this loop, row-comparison keys are treated the same as keys on their
* first (leftmost) columns. We'll add on lower-order columns of the row
* comparison below, if possible.
*
* The selected scan keys (at most one per index column) are remembered by
* storing their addresses into the local startKeys[] array.
*----------
@ -657,44 +661,91 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
{
ScanKey cur = startKeys[i];
/*
* _bt_preprocess_keys disallows it, but it's place to add some code
* later
*/
if (cur->sk_flags & SK_ISNULL)
elog(ERROR, "btree doesn't support is(not)null, yet");
Assert(cur->sk_attno == i+1);
/*
* If scankey operator is of default subtype, we can use the cached
* comparison procedure; otherwise gotta look it up in the catalogs.
*/
if (cur->sk_subtype == InvalidOid)
if (cur->sk_flags & SK_ROW_HEADER)
{
FmgrInfo *procinfo;
procinfo = index_getprocinfo(rel, i + 1, BTORDER_PROC);
ScanKeyEntryInitializeWithInfo(scankeys + i,
cur->sk_flags,
i + 1,
InvalidStrategy,
InvalidOid,
procinfo,
cur->sk_argument);
/*
* Row comparison header: look to the first row member instead.
*
* The member scankeys are already in insertion format (ie, they
* have sk_func = 3-way-comparison function), but we have to
* watch out for nulls, which _bt_preprocess_keys didn't check.
* A null in the first row member makes the condition unmatchable,
* just like qual_ok = false.
*/
cur = (ScanKey) DatumGetPointer(cur->sk_argument);
Assert(cur->sk_flags & SK_ROW_MEMBER);
if (cur->sk_flags & SK_ISNULL)
return false;
memcpy(scankeys + i, cur, sizeof(ScanKeyData));
/*
* If the row comparison is the last positioning key we accepted,
* try to add additional keys from the lower-order row members.
* (If we accepted independent conditions on additional index
* columns, we use those instead --- doesn't seem worth trying to
* determine which is more restrictive.) Note that this is OK
* even if the row comparison is of ">" or "<" type, because the
* condition applied to all but the last row member is effectively
* ">=" or "<=", and so the extra keys don't break the positioning
* scheme.
*/
if (i == keysCount - 1)
{
while (!(cur->sk_flags & SK_ROW_END))
{
cur++;
Assert(cur->sk_flags & SK_ROW_MEMBER);
if (cur->sk_attno != keysCount + 1)
break; /* out-of-sequence, can't use it */
if (cur->sk_flags & SK_ISNULL)
break; /* can't use null keys */
Assert(keysCount < INDEX_MAX_KEYS);
memcpy(scankeys + keysCount, cur, sizeof(ScanKeyData));
keysCount++;
}
break; /* done with outer loop */
}
}
else
{
RegProcedure cmp_proc;
/*
* Ordinary comparison key. Transform the search-style scan key
* to an insertion scan key by replacing the sk_func with the
* appropriate btree comparison function.
*
* If scankey operator is of default subtype, we can use the
* cached comparison function; otherwise gotta look it up in the
* catalogs.
*/
if (cur->sk_subtype == InvalidOid)
{
FmgrInfo *procinfo;
cmp_proc = get_opclass_proc(rel->rd_indclass->values[i],
cur->sk_subtype,
BTORDER_PROC);
ScanKeyEntryInitialize(scankeys + i,
cur->sk_flags,
i + 1,
InvalidStrategy,
cur->sk_subtype,
cmp_proc,
cur->sk_argument);
procinfo = index_getprocinfo(rel, cur->sk_attno, BTORDER_PROC);
ScanKeyEntryInitializeWithInfo(scankeys + i,
cur->sk_flags,
cur->sk_attno,
InvalidStrategy,
InvalidOid,
procinfo,
cur->sk_argument);
}
else
{
RegProcedure cmp_proc;
cmp_proc = get_opclass_proc(rel->rd_indclass->values[i],
cur->sk_subtype,
BTORDER_PROC);
ScanKeyEntryInitialize(scankeys + i,
cur->sk_flags,
cur->sk_attno,
InvalidStrategy,
cur->sk_subtype,
cmp_proc,
cur->sk_argument);
}
}
}

282
src/backend/access/nbtree/nbtutils.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtutils.c,v 1.69 2006/01/23 22:31:40 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtutils.c,v 1.70 2006/01/25 20:29:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -21,6 +21,12 @@
#include "executor/execdebug.h"
static void _bt_mark_scankey_required(ScanKey skey);
static bool _bt_check_rowcompare(ScanKey skey,
IndexTuple tuple, TupleDesc tupdesc,
ScanDirection dir, bool *continuescan);
/*
* _bt_mkscankey
* Build an insertion scan key that contains comparison data from itup
@ -218,6 +224,17 @@ _bt_formitem(IndexTuple itup)
* equality quals for all columns. In this case there can be at most one
* (visible) matching tuple. index_getnext uses this to avoid uselessly
* continuing the scan after finding one match.
*
* Row comparison keys are treated the same as comparisons to nondefault
* datatypes: we just transfer them into the preprocessed array without any
* editorialization. We can treat them the same as an ordinary inequality
* comparison on the row's first index column, for the purposes of the logic
* about required keys.
*
* Note: the reason we have to copy the preprocessed scan keys into private
* storage is that we are modifying the array based on comparisons of the
* key argument values, which could change on a rescan. Therefore we can't
* overwrite the caller's data structure.
*----------
*/
void
@ -273,26 +290,8 @@ _bt_preprocess_keys(IndexScanDesc scan)
memcpy(outkeys, inkeys, sizeof(ScanKeyData));
so->numberOfKeys = 1;
/* We can mark the qual as required if it's for first index col */
if (outkeys->sk_attno == 1)
{
switch (outkeys->sk_strategy)
{
case BTLessStrategyNumber:
case BTLessEqualStrategyNumber:
outkeys->sk_flags |= SK_BT_REQFWD;
break;
case BTEqualStrategyNumber:
outkeys->sk_flags |= (SK_BT_REQFWD | SK_BT_REQBKWD);
break;
case BTGreaterEqualStrategyNumber:
case BTGreaterStrategyNumber:
outkeys->sk_flags |= SK_BT_REQBKWD;
break;
default:
elog(ERROR, "unrecognized StrategyNumber: %d",
(int) outkeys->sk_strategy);
}
}
if (cur->sk_attno == 1)
_bt_mark_scankey_required(outkeys);
return;
}
@ -325,6 +324,7 @@ _bt_preprocess_keys(IndexScanDesc scan)
if (i < numberOfKeys)
{
/* See comments above: any NULL implies cannot match qual */
/* Note: we assume SK_ISNULL is never set in a row header key */
if (cur->sk_flags & SK_ISNULL)
{
so->qual_ok = false;
@ -432,26 +432,7 @@ _bt_preprocess_keys(IndexScanDesc scan)
memcpy(outkey, xform[j], sizeof(ScanKeyData));
if (priorNumberOfEqualCols == attno - 1)
{
switch (outkey->sk_strategy)
{
case BTLessStrategyNumber:
case BTLessEqualStrategyNumber:
outkey->sk_flags |= SK_BT_REQFWD;
break;
case BTEqualStrategyNumber:
outkey->sk_flags |= (SK_BT_REQFWD |
SK_BT_REQBKWD);
break;
case BTGreaterEqualStrategyNumber:
case BTGreaterStrategyNumber:
outkey->sk_flags |= SK_BT_REQBKWD;
break;
default:
elog(ERROR, "unrecognized StrategyNumber: %d",
(int) outkey->sk_strategy);
}
}
_bt_mark_scankey_required(outkey);
}
}
@ -470,11 +451,14 @@ _bt_preprocess_keys(IndexScanDesc scan)
/* check strategy this key's operator corresponds to */
j = cur->sk_strategy - 1;
/* if wrong RHS data type, punt */
if (cur->sk_subtype != InvalidOid)
/* if row comparison or wrong RHS data type, punt */
if ((cur->sk_flags & SK_ROW_HEADER) || cur->sk_subtype != InvalidOid)
{
memcpy(&outkeys[new_numberOfKeys++], cur,
sizeof(ScanKeyData));
ScanKey outkey = &outkeys[new_numberOfKeys++];
memcpy(outkey, cur, sizeof(ScanKeyData));
if (numberOfEqualCols == attno - 1)
_bt_mark_scankey_required(outkey);
if (j == (BTEqualStrategyNumber - 1))
hasOtherTypeEqual = true;
continue;
@ -514,6 +498,73 @@ _bt_preprocess_keys(IndexScanDesc scan)
scan->keys_are_unique = true;
}
/*
* Mark a scankey as "required to continue the scan".
*
* Depending on the operator type, the key may be required for both scan
* directions or just one. Also, if the key is a row comparison header,
* we have to mark the appropriate subsidiary ScanKeys as required. In
* such cases, the first subsidiary key is required, but subsequent ones
* are required only as long as they correspond to successive index columns.
* Otherwise the row comparison ordering is different from the index ordering
* and so we can't stop the scan on the basis of those lower-order columns.
*
* Note: when we set required-key flag bits in a subsidiary scankey, we are
* scribbling on a data structure belonging to the index AM's caller, not on
* our private copy. This should be OK because the marking will not change
* from scan to scan within a query, and so we'd just re-mark the same way
* anyway on a rescan. Something to keep an eye on though.
*/
static void
_bt_mark_scankey_required(ScanKey skey)
{
int addflags;
switch (skey->sk_strategy)
{
case BTLessStrategyNumber:
case BTLessEqualStrategyNumber:
addflags = SK_BT_REQFWD;
break;
case BTEqualStrategyNumber:
addflags = SK_BT_REQFWD | SK_BT_REQBKWD;
break;
case BTGreaterEqualStrategyNumber:
case BTGreaterStrategyNumber:
addflags = SK_BT_REQBKWD;
break;
default:
elog(ERROR, "unrecognized StrategyNumber: %d",
(int) skey->sk_strategy);
addflags = 0; /* keep compiler quiet */
break;
}
skey->sk_flags |= addflags;
if (skey->sk_flags & SK_ROW_HEADER)
{
ScanKey subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
AttrNumber attno = skey->sk_attno;
/* First subkey should be same as the header says */
Assert(subkey->sk_attno == attno);
for (;;)
{
Assert(subkey->sk_flags & SK_ROW_MEMBER);
Assert(subkey->sk_strategy == skey->sk_strategy);
if (subkey->sk_attno != attno)
break; /* non-adjacent key, so not required */
subkey->sk_flags |= addflags;
if (subkey->sk_flags & SK_ROW_END)
break;
subkey++;
attno++;
}
}
}
/*
* Test whether an indextuple satisfies all the scankey conditions.
*
@ -595,6 +646,14 @@ _bt_checkkeys(IndexScanDesc scan,
bool isNull;
Datum test;
/* row-comparison keys need special processing */
if (key->sk_flags & SK_ROW_HEADER)
{
if (_bt_check_rowcompare(key, tuple, tupdesc, dir, continuescan))
continue;
return false;
}
datum = index_getattr(tuple,
key->sk_attno,
tupdesc,
@ -660,3 +719,136 @@ _bt_checkkeys(IndexScanDesc scan,
return tuple_valid;
}
/*
* Test whether an indextuple satisfies a row-comparison scan condition.
*
* Return true if so, false if not. If not, also clear *continuescan if
* it's not possible for any future tuples in the current scan direction
* to pass the qual.
*
* This is a subroutine for _bt_checkkeys, which see for more info.
*/
static bool
_bt_check_rowcompare(ScanKey skey, IndexTuple tuple, TupleDesc tupdesc,
ScanDirection dir, bool *continuescan)
{
ScanKey subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
int32 cmpresult = 0;
bool result;
/* First subkey should be same as the header says */
Assert(subkey->sk_attno == skey->sk_attno);
/* Loop over columns of the row condition */
for (;;)
{
Datum datum;
bool isNull;
Assert(subkey->sk_flags & SK_ROW_MEMBER);
Assert(subkey->sk_strategy == skey->sk_strategy);
datum = index_getattr(tuple,
subkey->sk_attno,
tupdesc,
&isNull);
if (isNull)
{
/*
* Since NULLs are sorted after non-NULLs, we know we have reached
* the upper limit of the range of values for this index attr. On
* a forward scan, we can stop if this qual is one of the "must
* match" subset. On a backward scan, however, we should keep
* going.
*/
if ((subkey->sk_flags & SK_BT_REQFWD) &&
ScanDirectionIsForward(dir))
*continuescan = false;
/*
* In any case, this indextuple doesn't match the qual.
*/
return false;
}
if (subkey->sk_flags & SK_ISNULL)
{
/*
* Unlike the simple-scankey case, this isn't a disallowed case.
* But it can never match. If all the earlier row comparison
* columns are required for the scan direction, we can stop
* the scan, because there can't be another tuple that will
* succeed.
*/
if (subkey != (ScanKey) DatumGetPointer(skey->sk_argument))
subkey--;
if ((subkey->sk_flags & SK_BT_REQFWD) &&
ScanDirectionIsForward(dir))
*continuescan = false;
else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
ScanDirectionIsBackward(dir))
*continuescan = false;
return false;
}
/* Perform the test --- three-way comparison not bool operator */
cmpresult = DatumGetInt32(FunctionCall2(&subkey->sk_func,
datum,
subkey->sk_argument));
/* Done comparing if unequal, else advance to next column */
if (cmpresult != 0)
break;
if (subkey->sk_flags & SK_ROW_END)
break;
subkey++;
}
/*
* At this point cmpresult indicates the overall result of the row
* comparison, and subkey points to the deciding column (or the last
* column if the result is "=").
*/
switch (subkey->sk_strategy)
{
/* EQ and NE cases aren't allowed here */
case BTLessStrategyNumber:
result = (cmpresult < 0);
break;
case BTLessEqualStrategyNumber:
result = (cmpresult <= 0);
break;
case BTGreaterEqualStrategyNumber:
result = (cmpresult >= 0);
break;
case BTGreaterStrategyNumber:
result = (cmpresult > 0);
break;
default:
elog(ERROR, "unrecognized RowCompareType: %d",
(int) subkey->sk_strategy);
result = 0; /* keep compiler quiet */
break;
}
if (!result)
{
/*
* Tuple fails this qual. If it's a required qual for the current
* scan direction, then we can conclude no further tuples will
* pass, either. Note we have to look at the deciding column, not
* necessarily the first or last column of the row condition.
*/
if ((subkey->sk_flags & SK_BT_REQFWD) &&
ScanDirectionIsForward(dir))
*continuescan = false;
else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
ScanDirectionIsBackward(dir))
*continuescan = false;
}
return result;
}

30
src/backend/executor/nodeBitmapIndexscan.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/nodeBitmapIndexscan.c,v 1.14 2005/12/03 05:51:01 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/nodeBitmapIndexscan.c,v 1.15 2006/01/25 20:29:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -244,6 +244,20 @@ ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate)
#define BITMAPINDEXSCAN_NSLOTS 0
/*
* We do not open or lock the base relation here. We assume that an
* ancestor BitmapHeapScan node is holding AccessShareLock (or better)
* on the heap relation throughout the execution of the plan tree.
*/
indexstate->ss.ss_currentRelation = NULL;
indexstate->ss.ss_currentScanDesc = NULL;
/*
* Open the index relation.
*/
indexstate->biss_RelationDesc = index_open(node->indexid);
/*
* Initialize index-specific scan state
*/
@ -255,6 +269,7 @@ ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate)
* build the index scan keys from the index qualification
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->biss_RelationDesc,
node->indexqual,
node->indexstrategy,
node->indexsubtype,
@ -286,16 +301,8 @@ ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate)
}
/*
* We do not open or lock the base relation here. We assume that an
* ancestor BitmapHeapScan node is holding AccessShareLock (or better)
* on the heap relation throughout the execution of the plan tree.
*/
indexstate->ss.ss_currentRelation = NULL;
indexstate->ss.ss_currentScanDesc = NULL;
/*
* Open the index relation and initialize relation and scan descriptors.
* Initialize scan descriptor.
*
* Note we acquire no locks here; the index machinery does its own locks
* and unlocks. (We rely on having a lock on the parent table to
* ensure the index won't go away!) Furthermore, if the parent table
@ -303,7 +310,6 @@ ExecInitBitmapIndexScan(BitmapIndexScan *node, EState *estate)
* opened and write-locked the index, so we can tell the index machinery
* not to bother getting an extra lock.
*/
indexstate->biss_RelationDesc = index_open(node->indexid);
relistarget = ExecRelationIsTargetRelation(estate, node->scan.scanrelid);
indexstate->biss_ScanDesc =
index_beginscan_multi(indexstate->biss_RelationDesc,

196
src/backend/executor/nodeIndexscan.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.109 2005/12/03 05:51:02 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.110 2006/01/25 20:29:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -26,6 +26,7 @@
#include "access/genam.h"
#include "access/heapam.h"
#include "access/nbtree.h"
#include "executor/execdebug.h"
#include "executor/nodeIndexscan.h"
#include "miscadmin.h"
@ -504,6 +505,24 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
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 */
/*
* get the scan type from the relation descriptor.
*/
ExecAssignScanType(&indexstate->ss, RelationGetDescr(currentRelation), false);
/*
* Open the index relation.
*/
indexstate->iss_RelationDesc = index_open(node->indexid);
/*
* Initialize index-specific scan state
*/
@ -515,6 +534,7 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
* build the index scan keys from the index qualification
*/
ExecIndexBuildScanKeys((PlanState *) indexstate,
indexstate->iss_RelationDesc,
node->indexqual,
node->indexstrategy,
node->indexsubtype,
@ -545,20 +565,8 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
}
/*
* 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 */
/*
* get the scan type from the relation descriptor.
*/
ExecAssignScanType(&indexstate->ss, RelationGetDescr(currentRelation), false);
/*
* Open the index relation and initialize relation and scan descriptors.
* Initialize scan descriptor.
*
* Note we acquire no locks here; the index machinery does its own locks
* and unlocks. (We rely on having a lock on the parent table to
* ensure the index won't go away!) Furthermore, if the parent table
@ -566,7 +574,6 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
* opened and write-locked the index, so we can tell the index machinery
* not to bother getting an extra lock.
*/
indexstate->iss_RelationDesc = index_open(node->indexid);
relistarget = ExecRelationIsTargetRelation(estate, node->scan.scanrelid);
indexstate->iss_ScanDesc = index_beginscan(currentRelation,
indexstate->iss_RelationDesc,
@ -595,7 +602,7 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
* The index quals are passed to the index AM in the form of a ScanKey array.
* This routine sets up the ScanKeys, fills in all constant fields of the
* ScanKeys, and prepares information about the keys that have non-constant
* comparison values. We divide index qual expressions into three types:
* comparison values. We divide index qual expressions into four types:
*
* 1. Simple operator with constant comparison value ("indexkey op constant").
* For these, we just fill in a ScanKey containing the constant value.
@ -605,7 +612,12 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
* expression value, and set up an IndexRuntimeKeyInfo struct to drive
* evaluation of the expression at the right times.
*
* 3. ScalarArrayOpExpr ("indexkey op ANY (array-expression)"). For these,
* 3. RowCompareExpr ("(indexkey, indexkey, ...) op (expr, expr, ...)").
* For these, we create a header ScanKey plus a subsidiary ScanKey array,
* as specified in access/skey.h. The elements of the row comparison
* can have either constant or non-constant comparison values.
*
* 4. ScalarArrayOpExpr ("indexkey op ANY (array-expression)"). For these,
* we create a ScanKey with everything filled in except the comparison value,
* and set up an IndexArrayKeyInfo struct to drive processing of the qual.
* (Note that we treat all array-expressions as requiring runtime evaluation,
@ -614,10 +626,15 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
* Input params are:
*
* planstate: executor state node we are working for
* index: the index we are building scan keys for
* quals: indexquals expressions
* strategies: associated operator strategy numbers
* subtypes: associated operator subtype OIDs
*
* (Any elements of the strategies and subtypes lists that correspond to
* RowCompareExpr quals are not used here; instead we look up the info
* afresh.)
*
* Output params are:
*
* *scanKeys: receives ptr to array of ScanKeys
@ -631,8 +648,8 @@ ExecInitIndexScan(IndexScan *node, EState *estate)
* ScalarArrayOpExpr quals are not supported.
*/
void
ExecIndexBuildScanKeys(PlanState *planstate, List *quals,
List *strategies, List *subtypes,
ExecIndexBuildScanKeys(PlanState *planstate, Relation index,
List *quals, List *strategies, List *subtypes,
ScanKey *scanKeys, int *numScanKeys,
IndexRuntimeKeyInfo **runtimeKeys, int *numRuntimeKeys,
IndexArrayKeyInfo **arrayKeys, int *numArrayKeys)
@ -644,20 +661,42 @@ ExecIndexBuildScanKeys(PlanState *planstate, List *quals,
IndexRuntimeKeyInfo *runtime_keys;
IndexArrayKeyInfo *array_keys;
int n_scan_keys;
int extra_scan_keys;
int n_runtime_keys;
int n_array_keys;
int j;
/*
* If there are any RowCompareExpr quals, we need extra ScanKey entries
* for them, and possibly extra runtime-key entries. Count up what's
* needed. (The subsidiary ScanKey arrays for the RowCompareExprs could
* be allocated as separate chunks, but we have to count anyway to make
* runtime_keys large enough, so might as well just do one palloc.)
*/
n_scan_keys = list_length(quals);
scan_keys = (ScanKey) palloc(n_scan_keys * sizeof(ScanKeyData));
extra_scan_keys = 0;
foreach(qual_cell, quals)
{
if (IsA(lfirst(qual_cell), RowCompareExpr))
extra_scan_keys +=
list_length(((RowCompareExpr *) lfirst(qual_cell))->opnos);
}
scan_keys = (ScanKey)
palloc((n_scan_keys + extra_scan_keys) * sizeof(ScanKeyData));
/* Allocate these arrays as large as they could possibly need to be */
runtime_keys = (IndexRuntimeKeyInfo *)
palloc(n_scan_keys * sizeof(IndexRuntimeKeyInfo));
palloc((n_scan_keys + extra_scan_keys) * sizeof(IndexRuntimeKeyInfo));
array_keys = (IndexArrayKeyInfo *)
palloc0(n_scan_keys * sizeof(IndexArrayKeyInfo));
n_runtime_keys = 0;
n_array_keys = 0;
/*
* Below here, extra_scan_keys is index of first cell to use for next
* RowCompareExpr
*/
extra_scan_keys = n_scan_keys;
/*
* for each opclause in the given qual, convert each qual's opclause into
* a single scan key
@ -749,6 +788,119 @@ ExecIndexBuildScanKeys(PlanState *planstate, List *quals,
opfuncid, /* reg proc to use */
scanvalue); /* constant */
}
else if (IsA(clause, RowCompareExpr))
{
/* (indexkey, indexkey, ...) op (expression, expression, ...) */
RowCompareExpr *rc = (RowCompareExpr *) clause;
ListCell *largs_cell = list_head(rc->largs);
ListCell *rargs_cell = list_head(rc->rargs);
ListCell *opnos_cell = list_head(rc->opnos);
ScanKey first_sub_key = &scan_keys[extra_scan_keys];
/* Scan RowCompare columns and generate subsidiary ScanKey items */
while (opnos_cell != NULL)
{
ScanKey this_sub_key = &scan_keys[extra_scan_keys];
int flags = SK_ROW_MEMBER;
Datum scanvalue;
Oid opno;
Oid opclass;
int op_strategy;
Oid op_subtype;
bool op_recheck;
/*
* leftop should be the index key Var, possibly relabeled
*/
leftop = (Expr *) lfirst(largs_cell);
largs_cell = lnext(largs_cell);
if (leftop && IsA(leftop, RelabelType))
leftop = ((RelabelType *) leftop)->arg;
Assert(leftop != NULL);
if (!(IsA(leftop, Var) &&
var_is_rel((Var *) leftop)))
elog(ERROR, "indexqual doesn't have key on left side");
varattno = ((Var *) leftop)->varattno;
/*
* rightop is the constant or variable comparison value
*/
rightop = (Expr *) lfirst(rargs_cell);
rargs_cell = lnext(rargs_cell);
if (rightop && IsA(rightop, RelabelType))
rightop = ((RelabelType *) rightop)->arg;
Assert(rightop != NULL);
if (IsA(rightop, Const))
{
/* OK, simple constant comparison value */
scanvalue = ((Const *) rightop)->constvalue;
if (((Const *) rightop)->constisnull)
flags |= SK_ISNULL;
}
else
{
/* Need to treat this one as a runtime key */
runtime_keys[n_runtime_keys].scan_key = this_sub_key;
runtime_keys[n_runtime_keys].key_expr =
ExecInitExpr(rightop, planstate);
n_runtime_keys++;
scanvalue = (Datum) 0;
}
/*
* We have to look up the operator's associated btree support
* function
*/
opno = lfirst_oid(opnos_cell);
opnos_cell = lnext(opnos_cell);
if (index->rd_rel->relam != BTREE_AM_OID ||
varattno < 1 || varattno > index->rd_index->indnatts)
elog(ERROR, "bogus RowCompare index qualification");
opclass = index->rd_indclass->values[varattno - 1];
get_op_opclass_properties(opno, opclass,
&op_strategy, &op_subtype, &op_recheck);
if (op_strategy != rc->rctype)
elog(ERROR, "RowCompare index qualification contains wrong operator");
opfuncid = get_opclass_proc(opclass, op_subtype, BTORDER_PROC);
/*
* initialize the subsidiary scan key's fields appropriately
*/
ScanKeyEntryInitialize(this_sub_key,
flags,
varattno, /* attribute number */
op_strategy, /* op's strategy */
op_subtype, /* strategy subtype */
opfuncid, /* reg proc to use */
scanvalue); /* constant */
extra_scan_keys++;
}
/* Mark the last subsidiary scankey correctly */
scan_keys[extra_scan_keys - 1].sk_flags |= SK_ROW_END;
/*
* We don't use ScanKeyEntryInitialize for the header because
* it isn't going to contain a valid sk_func pointer.
*/
MemSet(this_scan_key, 0, sizeof(ScanKeyData));
this_scan_key->sk_flags = SK_ROW_HEADER;
this_scan_key->sk_attno = first_sub_key->sk_attno;
this_scan_key->sk_strategy = rc->rctype;
/* sk_subtype, sk_func not used in a header */
this_scan_key->sk_argument = PointerGetDatum(first_sub_key);
}
else if (IsA(clause, ScalarArrayOpExpr))
{
/* indexkey op ANY (array-expression) */

339
src/backend/optimizer/path/indxpath.c
View File

@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.196 2005/12/06 16:50:36 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.197 2006/01/25 20:29:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -61,6 +61,11 @@ static bool match_clause_to_indexcol(IndexOptInfo *index,
SaOpControl saop_control);
static bool is_indexable_operator(Oid expr_op, Oid opclass,
bool indexkey_on_left);
static bool match_rowcompare_to_indexcol(IndexOptInfo *index,
int indexcol,
Oid opclass,
RowCompareExpr *clause,
Relids outer_relids);
static Relids indexable_outerrelids(RelOptInfo *rel);
static bool matches_any_index(RestrictInfo *rinfo, RelOptInfo *rel,
Relids outer_relids);
@ -82,7 +87,10 @@ static bool match_special_index_operator(Expr *clause, Oid opclass,
bool indexkey_on_left);
static Expr *expand_boolean_index_clause(Node *clause, int indexcol,
IndexOptInfo *index);
static List *expand_indexqual_condition(RestrictInfo *rinfo, Oid opclass);
static List *expand_indexqual_opclause(RestrictInfo *rinfo, Oid opclass);
static RestrictInfo *expand_indexqual_rowcompare(RestrictInfo *rinfo,
IndexOptInfo *index,
int indexcol);
static List *prefix_quals(Node *leftop, Oid opclass,
Const *prefix, Pattern_Prefix_Status pstatus);
static List *network_prefix_quals(Node *leftop, Oid expr_op, Oid opclass,
@ -900,6 +908,14 @@ group_clauses_by_indexkey(IndexOptInfo *index,
* We do not actually do the commuting here, but we check whether a
* suitable commutator operator is available.
*
* It is also possible to match RowCompareExpr clauses to indexes (but
* currently, only btree indexes handle this). In this routine we will
* report a match if the first column of the row comparison matches the
* target index column. This is sufficient to guarantee that some index
* condition can be constructed from the RowCompareExpr --- whether the
* remaining columns match the index too is considered in
* expand_indexqual_rowcompare().
*
* It is also possible to match ScalarArrayOpExpr clauses to indexes, when
* the clause is of the form "indexkey op ANY (arrayconst)". Since the
* executor can only handle these in the context of bitmap index scans,
@ -944,7 +960,8 @@ match_clause_to_indexcol(IndexOptInfo *index,
/*
* Clause must be a binary opclause, or possibly a ScalarArrayOpExpr
* (which is always binary, by definition).
* (which is always binary, by definition). Or it could be a
* RowCompareExpr, which we pass off to match_rowcompare_to_indexcol().
*/
if (is_opclause(clause))
{
@ -972,6 +989,12 @@ match_clause_to_indexcol(IndexOptInfo *index,
expr_op = saop->opno;
plain_op = false;
}
else if (clause && IsA(clause, RowCompareExpr))
{
return match_rowcompare_to_indexcol(index, indexcol, opclass,
(RowCompareExpr *) clause,
outer_relids);
}
else
return false;
@ -1039,6 +1062,74 @@ is_indexable_operator(Oid expr_op, Oid opclass, bool indexkey_on_left)
return op_in_opclass(expr_op, opclass);
}
/*
* match_rowcompare_to_indexcol()
* Handles the RowCompareExpr case for match_clause_to_indexcol(),
* which see for comments.
*/
static bool
match_rowcompare_to_indexcol(IndexOptInfo *index,
int indexcol,
Oid opclass,
RowCompareExpr *clause,
Relids outer_relids)
{
Node *leftop,
*rightop;
Oid expr_op;
/* Forget it if we're not dealing with a btree index */
if (index->relam != BTREE_AM_OID)
return false;
/*
* We could do the matching on the basis of insisting that the opclass
* shown in the RowCompareExpr be the same as the index column's opclass,
* but that does not work well for cross-type comparisons (the opclass
* could be for the other datatype). Also it would fail to handle indexes
* using reverse-sort opclasses. Instead, match if the operator listed in
* the RowCompareExpr is the < <= > or >= member of the index opclass
* (after commutation, if the indexkey is on the right).
*/
leftop = (Node *) linitial(clause->largs);
rightop = (Node *) linitial(clause->rargs);
expr_op = linitial_oid(clause->opnos);
/*
* These syntactic tests are the same as in match_clause_to_indexcol()
*/
if (match_index_to_operand(leftop, indexcol, index) &&
bms_is_subset(pull_varnos(rightop), outer_relids) &&
!contain_volatile_functions(rightop))
{
/* OK, indexkey is on left */
}
else if (match_index_to_operand(rightop, indexcol, index) &&
bms_is_subset(pull_varnos(leftop), outer_relids) &&
!contain_volatile_functions(leftop))
{
/* indexkey is on right, so commute the operator */
expr_op = get_commutator(expr_op);
if (expr_op == InvalidOid)
return false;
}
else
return false;
/* We're good if the operator is the right type of opclass member */
switch (get_op_opclass_strategy(expr_op, opclass))
{
case BTLessStrategyNumber:
case BTLessEqualStrategyNumber:
case BTGreaterEqualStrategyNumber:
case BTGreaterStrategyNumber:
return true;
}
return false;
}
/****************************************************************************
* ---- ROUTINES TO DO PARTIAL INDEX PREDICATE TESTS ----
****************************************************************************/
@ -2014,7 +2105,8 @@ match_special_index_operator(Expr *clause, Oid opclass,
* of index qual clauses. Standard qual clauses (those in the index's
* opclass) are passed through unchanged. Boolean clauses and "special"
* index operators are expanded into clauses that the indexscan machinery
* will know what to do with.
* will know what to do with. RowCompare clauses are simplified if
* necessary to create a clause that is fully checkable by the index.
*
* The input list is ordered by index key, and so the output list is too.
* (The latter is not depended on by any part of the core planner, I believe,
@ -2041,13 +2133,14 @@ expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
foreach(l, (List *) lfirst(clausegroup_item))
{
RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
Expr *clause = rinfo->clause;
/* First check for boolean cases */
if (IsBooleanOpclass(curClass))
{
Expr *boolqual;
boolqual = expand_boolean_index_clause((Node *) rinfo->clause,
boolqual = expand_boolean_index_clause((Node *) clause,
indexcol,
index);
if (boolqual)
@ -2061,16 +2154,31 @@ expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
}
}
/* Next check for ScalarArrayOp cases */
if (IsA(rinfo->clause, ScalarArrayOpExpr))
/*
* Else it must be an opclause (usual case), ScalarArrayOp, or
* RowCompare
*/
if (is_opclause(clause))
{
resultquals = lappend(resultquals, rinfo);
continue;
resultquals = list_concat(resultquals,
expand_indexqual_opclause(rinfo,
curClass));
}
resultquals = list_concat(resultquals,
expand_indexqual_condition(rinfo,
curClass));
else if (IsA(clause, ScalarArrayOpExpr))
{
/* no extra work at this time */
resultquals = lappend(resultquals, rinfo);
}
else if (IsA(clause, RowCompareExpr))
{
resultquals = lappend(resultquals,
expand_indexqual_rowcompare(rinfo,
index,
indexcol));
}
else
elog(ERROR, "unsupported indexqual type: %d",
(int) nodeTag(clause));
}
clausegroup_item = lnext(clausegroup_item);
@ -2145,16 +2253,15 @@ expand_boolean_index_clause(Node *clause,
}
/*
* expand_indexqual_condition --- expand a single indexqual condition
* (other than a boolean-qual or ScalarArrayOp case)
* expand_indexqual_opclause --- expand a single indexqual condition
* that is an operator clause
*
* The input is a single RestrictInfo, the output a list of RestrictInfos
*/
static List *
expand_indexqual_condition(RestrictInfo *rinfo, Oid opclass)
expand_indexqual_opclause(RestrictInfo *rinfo, Oid opclass)
{
Expr *clause = rinfo->clause;
/* we know these will succeed */
Node *leftop = get_leftop(clause);
Node *rightop = get_rightop(clause);
@ -2224,6 +2331,204 @@ expand_indexqual_condition(RestrictInfo *rinfo, Oid opclass)
return result;
}
/*
* expand_indexqual_rowcompare --- expand a single indexqual condition
* that is a RowCompareExpr
*
* It's already known that the first column of the row comparison matches
* the specified column of the index. We can use additional columns of the
* row comparison as index qualifications, so long as they match the index
* in the "same direction", ie, the indexkeys are all on the same side of the
* clause and the operators are all the same-type members of the opclasses.
* If all the columns of the RowCompareExpr match in this way, we just use it
* as-is. Otherwise, we build a shortened RowCompareExpr (if more than one
* column matches) or a simple OpExpr (if the first-column match is all
* there is). In these cases the modified clause is always "<=" or ">="
* even when the original was "<" or ">" --- this is necessary to match all
* the rows that could match the original. (We are essentially building a
* lossy version of the row comparison when we do this.)
*/
static RestrictInfo *
expand_indexqual_rowcompare(RestrictInfo *rinfo,
IndexOptInfo *index,
int indexcol)
{
RowCompareExpr *clause = (RowCompareExpr *) rinfo->clause;
bool var_on_left;
int op_strategy;
Oid op_subtype;
bool op_recheck;
int matching_cols;
Oid expr_op;
List *opclasses;
List *subtypes;
List *new_ops;
ListCell *largs_cell;
ListCell *rargs_cell;
ListCell *opnos_cell;
/* We have to figure out (again) how the first col matches */
var_on_left = match_index_to_operand((Node *) linitial(clause->largs),
indexcol, index);
Assert(var_on_left ||
match_index_to_operand((Node *) linitial(clause->rargs),
indexcol, index));
expr_op = linitial_oid(clause->opnos);
if (!var_on_left)
expr_op = get_commutator(expr_op);
get_op_opclass_properties(expr_op, index->classlist[indexcol],
&op_strategy, &op_subtype, &op_recheck);
/* Build lists of the opclasses and operator subtypes in case needed */
opclasses = list_make1_oid(index->classlist[indexcol]);
subtypes = list_make1_oid(op_subtype);
/*
* See how many of the remaining columns match some index column
* in the same way. A note about rel membership tests: we assume
* that the clause as a whole is already known to use only Vars from
* the indexed relation and possibly some acceptable outer relations.
* So the "other" side of any potential index condition is OK as long
* as it doesn't use Vars from the indexed relation.
*/
matching_cols = 1;
largs_cell = lnext(list_head(clause->largs));
rargs_cell = lnext(list_head(clause->rargs));
opnos_cell = lnext(list_head(clause->opnos));
while (largs_cell != NULL)
{
Node *varop;
Node *constop;
int i;
expr_op = lfirst_oid(opnos_cell);
if (var_on_left)
{
varop = (Node *) lfirst(largs_cell);
constop = (Node *) lfirst(rargs_cell);
}
else
{
varop = (Node *) lfirst(rargs_cell);
constop = (Node *) lfirst(largs_cell);
/* indexkey is on right, so commute the operator */
expr_op = get_commutator(expr_op);
if (expr_op == InvalidOid)
break; /* operator is not usable */
}
if (bms_is_member(index->rel->relid, pull_varnos(constop)))
break; /* no good, Var on wrong side */
if (contain_volatile_functions(constop))
break; /* no good, volatile comparison value */
/*
* The Var side can match any column of the index. If the user
* does something weird like having multiple identical index
* columns, we insist the match be on the first such column,
* to avoid confusing the executor.
*/
for (i = 0; i < index->ncolumns; i++)
{
if (match_index_to_operand(varop, i, index))
break;
}
if (i >= index->ncolumns)
break; /* no match found */
/* Now, do we have the right operator for this column? */
if (get_op_opclass_strategy(expr_op, index->classlist[i])
!= op_strategy)
break;
/* Add opclass and subtype to lists */
get_op_opclass_properties(expr_op, index->classlist[i],
&op_strategy, &op_subtype, &op_recheck);
opclasses = lappend_oid(opclasses, index->classlist[i]);
subtypes = lappend_oid(subtypes, op_subtype);
/* This column matches, keep scanning */
matching_cols++;
largs_cell = lnext(largs_cell);
rargs_cell = lnext(rargs_cell);
opnos_cell = lnext(opnos_cell);
}
/* Return clause as-is if it's all usable as index quals */
if (matching_cols == list_length(clause->opnos))
return rinfo;
/*
* We have to generate a subset rowcompare (possibly just one OpExpr).
* The painful part of this is changing < to <= or > to >=, so deal with
* that first.
*/
if (op_strategy == BTLessEqualStrategyNumber ||
op_strategy == BTGreaterEqualStrategyNumber)
{
/* easy, just use the same operators */
new_ops = list_truncate(list_copy(clause->opnos), matching_cols);
}
else
{
ListCell *opclasses_cell;
ListCell *subtypes_cell;
if (op_strategy == BTLessStrategyNumber)
op_strategy = BTLessEqualStrategyNumber;
else if (op_strategy == BTGreaterStrategyNumber)
op_strategy = BTGreaterEqualStrategyNumber;
else
elog(ERROR, "unexpected strategy number %d", op_strategy);
new_ops = NIL;
forboth(opclasses_cell, opclasses, subtypes_cell, subtypes)
{
expr_op = get_opclass_member(lfirst_oid(opclasses_cell),
lfirst_oid(subtypes_cell),
op_strategy);
if (!OidIsValid(expr_op)) /* should not happen */
elog(ERROR, "could not find member %d of opclass %u",
op_strategy, lfirst_oid(opclasses_cell));
if (!var_on_left)
{
expr_op = get_commutator(expr_op);
if (!OidIsValid(expr_op)) /* should not happen */
elog(ERROR, "could not find commutator of member %d of opclass %u",
op_strategy, lfirst_oid(opclasses_cell));
}
new_ops = lappend_oid(new_ops, expr_op);
}
}
/* If we have more than one matching col, create a subset rowcompare */
if (matching_cols > 1)
{
RowCompareExpr *rc = makeNode(RowCompareExpr);
if (var_on_left)
rc->rctype = (RowCompareType) op_strategy;
else
rc->rctype = (op_strategy == BTLessEqualStrategyNumber) ?
ROWCOMPARE_GE : ROWCOMPARE_LE;
rc->opnos = new_ops;
rc->opclasses = list_truncate(list_copy(clause->opclasses),
matching_cols);
rc->largs = list_truncate((List *) copyObject(clause->largs),
matching_cols);
rc->rargs = list_truncate((List *) copyObject(clause->rargs),
matching_cols);
return make_restrictinfo((Expr *) rc, true, false, NULL);
}
else
{
Expr *opexpr;
opexpr = make_opclause(linitial_oid(new_ops), BOOLOID, false,
copyObject(linitial(clause->largs)),
copyObject(linitial(clause->rargs)));
return make_restrictinfo(opexpr, true, false, NULL);
}
}
/*
* Given a fixed prefix that all the "leftop" values must have,
* generate suitable indexqual condition(s). opclass is the index

41
src/backend/optimizer/plan/createplan.c
View File

@ -10,7 +10,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.205 2005/11/26 22:14:56 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.206 2006/01/25 20:29:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -1583,7 +1583,7 @@ fix_indexqual_references(List *indexquals, IndexPath *index_path,
* (only) the base relation.
*/
if (!bms_equal(rinfo->left_relids, index->rel->relids))
CommuteClause(op);
CommuteOpExpr(op);
/*
* Now, determine which index attribute this is, change the
@ -1594,6 +1594,41 @@ fix_indexqual_references(List *indexquals, IndexPath *index_path,
&opclass);
clause_op = op->opno;
}
else if (IsA(clause, RowCompareExpr))
{
RowCompareExpr *rc = (RowCompareExpr *) clause;
ListCell *lc;
/*
* Check to see if the indexkey is on the right; if so, commute
* the clause. The indexkey should be the side that refers to
* (only) the base relation.
*/
if (!bms_overlap(pull_varnos(linitial(rc->largs)),
index->rel->relids))
CommuteRowCompareExpr(rc);
/*
* For each column in the row comparison, determine which index
* attribute this is and change the indexkey operand as needed.
*
* Save the index opclass for only the first column. We will
* return the operator and opclass info for just the first
* column of the row comparison; the executor will have to
* look up the rest if it needs them.
*/
foreach(lc, rc->largs)
{
Oid tmp_opclass;
lfirst(lc) = fix_indexqual_operand(lfirst(lc),
index,
&tmp_opclass);
if (lc == list_head(rc->largs))
opclass = tmp_opclass;
}
clause_op = linitial_oid(rc->opnos);
}
else if (IsA(clause, ScalarArrayOpExpr))
{
ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;
@ -1745,7 +1780,7 @@ get_switched_clauses(List *clauses, Relids outerrelids)
temp->opretset = clause->opretset;
temp->args = list_copy(clause->args);
/* Commute it --- note this modifies the temp node in-place. */
CommuteClause(temp);
CommuteOpExpr(temp);
t_list = lappend(t_list, temp);
}
else

73
src/backend/optimizer/util/clauses.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.205 2005/12/28 01:30:00 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.206 2006/01/25 20:29:23 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@ -1167,12 +1167,12 @@ NumRelids(Node *clause)
}
/*
* CommuteClause: commute a binary operator clause
* CommuteOpExpr: commute a binary operator clause
*
* XXX the clause is destructively modified!
*/
void
CommuteClause(OpExpr *clause)
CommuteOpExpr(OpExpr *clause)
{
Oid opoid;
Node *temp;
@ -1200,6 +1200,73 @@ CommuteClause(OpExpr *clause)
lsecond(clause->args) = temp;
}
/*
* CommuteRowCompareExpr: commute a RowCompareExpr clause
*
* XXX the clause is destructively modified!
*/
void
CommuteRowCompareExpr(RowCompareExpr *clause)
{
List *newops;
List *temp;
ListCell *l;
/* Sanity checks: caller is at fault if these fail */
if (!IsA(clause, RowCompareExpr))
elog(ERROR, "expected a RowCompareExpr");
/* Build list of commuted operators */
newops = NIL;
foreach(l, clause->opnos)
{
Oid opoid = lfirst_oid(l);
opoid = get_commutator(opoid);
if (!OidIsValid(opoid))
elog(ERROR, "could not find commutator for operator %u",
lfirst_oid(l));
newops = lappend_oid(newops, opoid);
}
/*
* modify the clause in-place!
*/
switch (clause->rctype)
{
case ROWCOMPARE_LT:
clause->rctype = ROWCOMPARE_GT;
break;
case ROWCOMPARE_LE:
clause->rctype = ROWCOMPARE_GE;
break;
case ROWCOMPARE_GE:
clause->rctype = ROWCOMPARE_LE;
break;
case ROWCOMPARE_GT:
clause->rctype = ROWCOMPARE_LT;
break;
default:
elog(ERROR, "unexpected RowCompare type: %d",
(int) clause->rctype);
break;
}
clause->opnos = newops;
/*
* Note: we don't bother to update the opclasses list, but just set
* it to empty. This is OK since this routine is currently only used
* for index quals, and the index machinery won't use the opclass
* information. The original opclass list is NOT valid if we have
* commuted any cross-type comparisons, so don't leave it in place.
*/
clause->opclasses = NIL; /* XXX */
temp = clause->largs;
clause->largs = clause->rargs;
clause->rargs = temp;
}
/*
* strip_implicit_coercions: remove implicit coercions at top level of tree
*

13
src/backend/utils/adt/selfuncs.c
View File

@ -15,7 +15,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.196 2006/01/14 00:14:11 tgl Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.197 2006/01/25 20:29:24 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -4657,6 +4657,9 @@ btcostestimate(PG_FUNCTION_ARGS)
* to find out which ones count as boundary quals. We rely on the
* knowledge that they are given in index column order.
*
* For a RowCompareExpr, we consider only the first column, just as
* rowcomparesel() does.
*
* If there's a ScalarArrayOpExpr in the quals, we'll actually perform
* N index scans not one, but the ScalarArrayOpExpr's operator can be
* considered to act the same as it normally does.
@ -4682,6 +4685,14 @@ btcostestimate(PG_FUNCTION_ARGS)
rightop = get_rightop(clause);
clause_op = ((OpExpr *) clause)->opno;
}
else if (IsA(clause, RowCompareExpr))
{
RowCompareExpr *rc = (RowCompareExpr *) clause;
leftop = (Node *) linitial(rc->largs);
rightop = (Node *) linitial(rc->rargs);
clause_op = linitial_oid(rc->opnos);
}
else if (IsA(clause, ScalarArrayOpExpr))
{
ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;

35
src/include/access/skey.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/skey.h,v 1.30 2006/01/14 22:03:35 tgl Exp $
* $PostgreSQL: pgsql/src/include/access/skey.h,v 1.31 2006/01/25 20:29:24 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -69,6 +69,36 @@ typedef struct ScanKeyData
typedef ScanKeyData *ScanKey;
/*
* About row comparisons:
*
* The ScanKey data structure also supports row comparisons, that is ordered
* tuple comparisons like (x, y) > (c1, c2), having the SQL-spec semantics
* "x > c1 OR (x = c1 AND y > c2)". Note that this is currently only
* implemented for btree index searches, not for heapscans or any other index
* type. A row comparison is represented by a "header" ScanKey entry plus
* a separate array of ScanKeys, one for each column of the row comparison.
* The header entry has these properties:
* sk_flags = SK_ROW_HEADER
* sk_attno = index column number for leading column of row comparison
* sk_strategy = btree strategy code for semantics of row comparison
* (ie, < <= > or >=)
* sk_subtype, sk_func: not used
* sk_argument: pointer to subsidiary ScanKey array
* If the header is part of a ScanKey array that's sorted by attno, it
* must be sorted according to the leading column number.
*
* The subsidiary ScanKey array appears in logical column order of the row
* comparison, which may be different from index column order. The array
* elements are like a normal ScanKey array except that:
* sk_flags must include SK_ROW_MEMBER, plus SK_ROW_END in the last
* element (needed since row header does not include a count)
* sk_func points to the btree comparison support function for the
* opclass, NOT the operator's implementation function.
* sk_strategy must be the same in all elements of the subsidiary array,
* that is, the same as in the header entry.
*/
/*
* ScanKeyData sk_flags
*
@ -78,6 +108,9 @@ typedef ScanKeyData *ScanKey;
*/
#define SK_ISNULL 0x0001 /* sk_argument is NULL */
#define SK_UNARY 0x0002 /* unary operator (currently unsupported) */
#define SK_ROW_HEADER 0x0004 /* row comparison header (see above) */
#define SK_ROW_MEMBER 0x0008 /* row comparison member (see above) */
#define SK_ROW_END 0x0010 /* last row comparison member (see above) */
/*

6
src/include/executor/nodeIndexscan.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/executor/nodeIndexscan.h,v 1.25 2005/11/25 19:47:50 tgl Exp $
* $PostgreSQL: pgsql/src/include/executor/nodeIndexscan.h,v 1.26 2006/01/25 20:29:24 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -25,8 +25,8 @@ extern void ExecIndexRestrPos(IndexScanState *node);
extern void ExecIndexReScan(IndexScanState *node, ExprContext *exprCtxt);
/* routines exported to share code with nodeBitmapIndexscan.c */
extern void ExecIndexBuildScanKeys(PlanState *planstate, List *quals,
List *strategies, List *subtypes,
extern void ExecIndexBuildScanKeys(PlanState *planstate, Relation index,
List *quals, List *strategies, List *subtypes,
ScanKey *scanKeys, int *numScanKeys,
IndexRuntimeKeyInfo **runtimeKeys, int *numRuntimeKeys,
IndexArrayKeyInfo **arrayKeys, int *numArrayKeys);

6
src/include/optimizer/clauses.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/optimizer/clauses.h,v 1.81 2005/12/20 02:30:36 tgl Exp $
* $PostgreSQL: pgsql/src/include/optimizer/clauses.h,v 1.82 2006/01/25 20:29:24 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -67,7 +67,9 @@ extern bool has_distinct_clause(Query *query);
extern bool has_distinct_on_clause(Query *query);
extern int NumRelids(Node *clause);
extern void CommuteClause(OpExpr *clause);
extern void CommuteOpExpr(OpExpr *clause);
extern void CommuteRowCompareExpr(RowCompareExpr *clause);
extern Node *strip_implicit_coercions(Node *node);