/*
* Setup a ScanKey for a search in the relation 'rel' for a tuple 'key' that
* is setup to match 'rel' (*NOT* idxrel!).
*
* Returns whether any column contains NULLs.
*
* This is not generic routine, it expects the idxrel to be replication
* identity of a rel and meet all limitations associated with that.
*/
static bool
build_replindex_scan_key(ScanKey skey, Relation rel, Relation idxrel,
TupleTableSlot *searchslot)
{
int attoff;
bool isnull;
Datum indclassDatum;
oidvector *opclass;
int2vector *indkey = &idxrel->rd_index->indkey;
bool hasnulls = false;
Assert(RelationGetReplicaIndex(rel) == RelationGetRelid(idxrel));
indclassDatum = SysCacheGetAttr(INDEXRELID, idxrel->rd_indextuple,
Anum_pg_index_indclass, &isnull);
Assert(!isnull);
opclass = (oidvector *) DatumGetPointer(indclassDatum);
/* Build scankey for every attribute in the index. */
for (attoff = 0; attoff < IndexRelationGetNumberOfKeyAttributes(idxrel); attoff++)
{
Oid operator;
Oid opfamily;
RegProcedure regop;
int pkattno = attoff + 1;
int mainattno = indkey->values[attoff];
Oid optype = get_opclass_input_type(opclass->values[attoff]);
/*
* Load the operator info. We need this to get the equality operator
* function for the scan key.
*/
opfamily = get_opclass_family(opclass->values[attoff]);
operator = get_opfamily_member(opfamily, optype,
optype,
BTEqualStrategyNumber);
if (!OidIsValid(operator))
elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
BTEqualStrategyNumber, optype, optype, opfamily);
regop = get_opcode(operator);
/* Initialize the scankey. */
ScanKeyInit(&skey[attoff],
pkattno,
BTEqualStrategyNumber,
regop,
searchslot->tts_values[mainattno - 1]);
/* Check for null value. */
if (searchslot->tts_isnull[mainattno - 1])
{
hasnulls = true;
skey[attoff].sk_flags |= SK_ISNULL;
}
}
return hasnulls;
}
/*
* get_op_btree_interpretation
* Given an operator's OID, find out which btree opclasses it belongs to,
* and what strategy number it has within each one. The results are
* returned as an OID list and a parallel integer list.
*
* In addition to the normal btree operators, we consider a <> operator to be
* a "member" of an opclass if its negator is the opclass' equality operator.
* ROWCOMPARE_NE is returned as the strategy number for this case.
*/
void
get_op_btree_interpretation(Oid opno, List **opclasses, List **opstrats)
{
Oid lefttype,
righttype;
CatCList *catlist;
bool op_negated;
int i;
*opclasses = NIL;
*opstrats = NIL;
/*
* Get the nominal left-hand input type of the operator; we will ignore
* opclasses that don't have that as the expected input datatype. This is
* a kluge to avoid being confused by binary-compatible opclasses (such as
* text_ops and varchar_ops, which share the same operators).
*/
op_input_types(opno, &lefttype, &righttype);
Assert(OidIsValid(lefttype));
/*
* Find all the pg_amop entries containing the operator.
*/
catlist = SearchSysCacheList(AMOPOPID, 1,
ObjectIdGetDatum(opno),
0, 0, 0);
/*
* If we can't find any opclass containing the op, perhaps it is a <>
* operator. See if it has a negator that is in an opclass.
*/
op_negated = false;
if (catlist->n_members == 0)
{
Oid op_negator = get_negator(opno);
if (OidIsValid(op_negator))
{
op_negated = true;
ReleaseSysCacheList(catlist);
catlist = SearchSysCacheList(AMOPOPID, 1,
ObjectIdGetDatum(op_negator),
0, 0, 0);
}
}
/* Now search the opclasses */
for (i = 0; i < catlist->n_members; i++)
{
HeapTuple op_tuple = &catlist->members[i]->tuple;
Form_pg_amop op_form = (Form_pg_amop) GETSTRUCT(op_tuple);
Oid opclass_id;
StrategyNumber op_strategy;
opclass_id = op_form->amopclaid;
/* must be btree */
if (!opclass_is_btree(opclass_id))
continue;
/* must match operator input type exactly */
if (get_opclass_input_type(opclass_id) != lefttype)
continue;
/* Get the operator's btree strategy number */
op_strategy = (StrategyNumber) op_form->amopstrategy;
Assert(op_strategy >= 1 && op_strategy <= 5);
if (op_negated)
{
/* Only consider negators that are = */
if (op_strategy != BTEqualStrategyNumber)
continue;
op_strategy = ROWCOMPARE_NE;
}
*opclasses = lappend_oid(*opclasses, opclass_id);
*opstrats = lappend_int(*opstrats, op_strategy);
}
ReleaseSysCacheList(catlist);
}
