diff options
| -rw-r--r-- | src/backend/commands/tablecmds.c | 57 |
1 files changed, 23 insertions, 34 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 94660e4bd45..5823fce9340 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -10082,6 +10082,8 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel, Oid amid; Oid opfamily; Oid opcintype; + bool for_overlaps; + CompareType cmptype; Oid pfeqop; Oid ppeqop; Oid ffeqop; @@ -10098,40 +10100,27 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel, opcintype = cla_tup->opcintype; ReleaseSysCache(cla_ht); - if (with_period) - { - CompareType cmptype; - bool for_overlaps = with_period && i == numpks - 1; - - cmptype = for_overlaps ? COMPARE_OVERLAP : COMPARE_EQ; - - /* - * An index AM can use whatever strategy numbers it wants, so we - * ask it what number it actually uses. - */ - eqstrategy = IndexAmTranslateCompareType(cmptype, amid, opfamily, opcintype, true); - if (eqstrategy == InvalidStrategy) - ereport(ERROR, - errcode(ERRCODE_UNDEFINED_OBJECT), - for_overlaps - ? errmsg("could not identify an overlaps operator for foreign key") - : errmsg("could not identify an equality operator for foreign key"), - errdetail("Could not translate compare type %d for operator family \"%s\", input type %s, access method \"%s\".", - cmptype, get_opfamily_name(opfamily, false), format_type_be(opcintype), get_am_name(amid))); - } - else - { - /* - * Check it's a btree; currently this can never fail since no - * other index AMs support unique indexes. If we ever did have - * other types of unique indexes, we'd need a way to determine - * which operator strategy number is equality. (We could use - * IndexAmTranslateCompareType.) - */ - if (amid != BTREE_AM_OID) - elog(ERROR, "only b-tree indexes are supported for foreign keys"); - eqstrategy = BTEqualStrategyNumber; - } + /* + * Get strategy number from index AM. + * + * For a normal foreign-key constraint, this should not fail, since we + * already checked that the index is unique and should therefore have + * appropriate equal operators. For a period foreign key, this could + * fail if we selected a non-matching exclusion constraint earlier. + * (XXX Maybe we should do these lookups earlier so we don't end up + * doing that.) + */ + for_overlaps = with_period && i == numpks - 1; + cmptype = for_overlaps ? COMPARE_OVERLAP : COMPARE_EQ; + eqstrategy = IndexAmTranslateCompareType(cmptype, amid, opfamily, opcintype, true); + if (eqstrategy == InvalidStrategy) + ereport(ERROR, + errcode(ERRCODE_UNDEFINED_OBJECT), + for_overlaps + ? errmsg("could not identify an overlaps operator for foreign key") + : errmsg("could not identify an equality operator for foreign key"), + errdetail("Could not translate compare type %d for operator family \"%s\", input type %s, access method \"%s\".", + cmptype, get_opfamily_name(opfamily, false), format_type_be(opcintype), get_am_name(amid))); /* * There had better be a primary equality operator for the index. |