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Restructure operator classes to allow improved handling of cross-data-type

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cases.  Operator classes now exist within "operator families".  While most
families are equivalent to a single class, related classes can be grouped
into one family to represent the fact that they are semantically compatible.
Cross-type operators are now naturally adjunct parts of a family, without
having to wedge them into a particular opclass as we had done originally.

This commit restructures the catalogs and cleans up enough of the fallout so
that everything still works at least as well as before, but most of the work
needed to actually improve the planner's behavior will come later.  Also,
there are not yet CREATE/DROP/ALTER OPERATOR FAMILY commands; the only way
to create a new family right now is to allow CREATE OPERATOR CLASS to make
one by default.  I owe some more documentation work, too.  But that can all
be done in smaller pieces once this infrastructure is in place.
This commit is contained in:
Tom Lane
2006-12-23 00:43:13 +00:00
parent d31ccb6c3e
commit a78fcfb512
76 changed files with 4753 additions and 4100 deletions
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37
src/backend/utils/sort/tuplesort.c
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@@ -91,7 +91,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/sort/tuplesort.c,v 1.70 2006/10/04 00:30:04 momjian Exp $
* $PostgreSQL: pgsql/src/backend/utils/sort/tuplesort.c,v 1.71 2006/12/23 00:43:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -2104,15 +2104,16 @@ SelectSortFunction(Oid sortOperator,
int i;
HeapTuple tuple;
Form_pg_operator optup;
Oid opclass = InvalidOid;
Oid opfamily = InvalidOid;
Oid opinputtype = InvalidOid;
/*
* Search pg_amop to see if the target operator is registered as the "<"
* or ">" operator of any btree opclass. It's possible that it might be
* Search pg_amop to see if the target operator is registered as a "<"
* or ">" operator of any btree opfamily. It's possible that it might be
* registered both ways (eg, if someone were to build a "reverse sort"
* opclass for some reason); prefer the "<" case if so. If the operator is
* registered the same way in multiple opclasses, assume we can use the
* associated comparator function from any one.
* opfamily); prefer the "<" case if so. If the operator is registered the
* same way in multiple opfamilies, assume we can use the associated
* comparator function from any one.
*/
catlist = SearchSysCacheList(AMOPOPID, 1,
ObjectIdGetDatum(sortOperator),
@@ -2125,21 +2126,24 @@ SelectSortFunction(Oid sortOperator,
tuple = &catlist->members[i]->tuple;
aform = (Form_pg_amop) GETSTRUCT(tuple);
if (!opclass_is_btree(aform->amopclaid))
/* must be btree */
if (aform->amopmethod != BTREE_AM_OID)
continue;
/* must be of default subtype, too */
if (aform->amopsubtype != InvalidOid)
/* mustn't be cross-datatype, either */
if (aform->amoplefttype != aform->amoprighttype)
continue;
if (aform->amopstrategy == BTLessStrategyNumber)
{
opclass = aform->amopclaid;
opfamily = aform->amopfamily;
opinputtype = aform->amoplefttype;
*kind = SORTFUNC_CMP;
break; /* done looking */
}
else if (aform->amopstrategy == BTGreaterStrategyNumber)
{
opclass = aform->amopclaid;
opfamily = aform->amopfamily;
opinputtype = aform->amoplefttype;
*kind = SORTFUNC_REVCMP;
/* keep scanning in hopes of finding a BTLess entry */
}
@@ -2147,10 +2151,13 @@ SelectSortFunction(Oid sortOperator,
ReleaseSysCacheList(catlist);
if (OidIsValid(opclass))
if (OidIsValid(opfamily))
{
/* Found a suitable opclass, get its default comparator function */
*sortFunction = get_opclass_proc(opclass, InvalidOid, BTORDER_PROC);
/* Found a suitable opfamily, get the matching comparator function */
*sortFunction = get_opfamily_proc(opfamily,
opinputtype,
opinputtype,
BTORDER_PROC);
Assert(RegProcedureIsValid(*sortFunction));
return;
}