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Replace inefficient _bt_invokestrat calls with direct calls to the

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appropriate btree three-way comparison routine.  Not clear why the
three-way comparison routines were being used in some paths and not
others in btree --- incomplete changes by someone long ago, maybe?
Anyway, this makes for a nice speedup in CREATE INDEX.
This commit is contained in:
Tom Lane
2000-02-18 06:32:39 +00:00
parent 49353692d1
commit 8cb624262a
7 changed files with 272 additions and 294 deletions
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75
src/backend/utils/sort/tuplesort.c
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@ -78,7 +78,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/sort/tuplesort.c,v 1.5 2000/01/26 05:57:33 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/sort/tuplesort.c,v 1.6 2000/02/18 06:32:30 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -253,6 +253,7 @@ struct Tuplesortstate
* by tuplesort_begin_index and used only by the IndexTuple routines.
*/
Relation indexRel;
ScanKey indexScanKey;
bool enforceUnique; /* complain if we find duplicate tuples */
/*
@ -476,6 +477,8 @@ tuplesort_begin_index(Relation indexRel,
state->tuplesize = tuplesize_index;
state->indexRel = indexRel;
/* see comments below about btree dependence of this code... */
state->indexScanKey = _bt_mkscankey_nodata(indexRel);
state->enforceUnique = enforceUnique;
return state;
@ -1745,40 +1748,56 @@ tuplesize_heap(Tuplesortstate *state, void *tup)
static int
comparetup_index(Tuplesortstate *state, const void *a, const void *b)
{
IndexTuple ltup = (IndexTuple) a;
IndexTuple rtup = (IndexTuple) b;
TupleDesc itdesc = state->indexRel->rd_att;
bool equal_isnull = false;
/*
* This is almost the same as _bt_tuplecompare(), but we need to
* keep track of whether any null fields are present.
*/
IndexTuple tuple1 = (IndexTuple) a;
IndexTuple tuple2 = (IndexTuple) b;
Relation rel = state->indexRel;
Size keysz = RelationGetNumberOfAttributes(rel);
ScanKey scankey = state->indexScanKey;
TupleDesc tupDes;
int i;
bool equal_hasnull = false;
for (i = 1; i <= itdesc->natts; i++)
tupDes = RelationGetDescr(rel);
for (i = 1; i <= keysz; i++)
{
Datum lattr,
rattr;
bool isnull1,
isnull2;
ScanKey entry = &scankey[i - 1];
Datum attrDatum1,
attrDatum2;
bool isFirstNull,
isSecondNull;
int32 compare;
lattr = index_getattr(ltup, i, itdesc, &isnull1);
rattr = index_getattr(rtup, i, itdesc, &isnull2);
attrDatum1 = index_getattr(tuple1, i, tupDes, &isFirstNull);
attrDatum2 = index_getattr(tuple2, i, tupDes, &isSecondNull);
if (isnull1)
/* see comments about NULLs handling in btbuild */
if (isFirstNull) /* attr in tuple1 is NULL */
{
if (!isnull2)
return 1; /* NULL sorts after non-NULL */
equal_isnull = true;
continue;
if (isSecondNull) /* attr in tuple2 is NULL too */
{
compare = 0;
equal_hasnull = true;
}
else
compare = 1; /* NULL ">" not-NULL */
}
else if (isSecondNull) /* attr in tuple1 is NOT_NULL and */
{ /* attr in tuple2 is NULL */
compare = -1; /* not-NULL "<" NULL */
}
else
{
compare = (int32) FMGR_PTR2(&entry->sk_func,
attrDatum1, attrDatum2);
}
else if (isnull2)
return -1;
if (_bt_invokestrat(state->indexRel, i,
BTGreaterStrategyNumber,
lattr, rattr))
return 1;
if (_bt_invokestrat(state->indexRel, i,
BTGreaterStrategyNumber,
rattr, lattr))
return -1;
if (compare != 0)
return (int) compare; /* done when we find unequal attributes */
}
/*
@ -1790,7 +1809,7 @@ comparetup_index(Tuplesortstate *state, const void *a, const void *b)
* the sort algorithm wouldn't have checked whether one must appear
* before the other.
*/
if (state->enforceUnique && !equal_isnull)
if (state->enforceUnique && !equal_hasnull)
elog(ERROR, "Cannot create unique index. Table contains non-unique values");
return 0;