From 8e60c2423acd31fd0507059b025a13efe69d02cd Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 9 Jul 2010 22:57:47 +0000 Subject: [PATCH] Avoid an Assert failure in deconstruct_array() by making get_attstatsslot() use the actual element type of the array it's disassembling, rather than trusting the type OID passed in by its caller. This is needed because sometimes the planner passes in a type OID that's only binary-compatible with the target column's type, rather than being an exact match. Per an example from Bernd Helmle. Possibly we should refactor get_attstatsslot/free_attstatsslot to not expect the caller to supply type ID data at all, but for now I'll just do the minimum-change fix. Back-patch to 7.4. Bernd's test case only crashes back to 8.0, but since these subroutines are the same in 7.4, I suspect there may be variant cases that would crash 7.4 as well. --- src/backend/utils/cache/lsyscache.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c index cc33c459a2..db5b3c7596 100644 --- a/src/backend/utils/cache/lsyscache.c +++ b/src/backend/utils/cache/lsyscache.c @@ -7,7 +7,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/cache/lsyscache.c,v 1.170 2010/04/24 16:20:32 sriggs Exp $ + * $PostgreSQL: pgsql/src/backend/utils/cache/lsyscache.c,v 1.170.2.1 2010/07/09 22:57:47 tgl Exp $ * * NOTES * Eventually, the index information should go through here, too. @@ -2463,6 +2463,10 @@ get_attavgwidth(Oid relid, AttrNumber attnum) * If the attribute type is pass-by-reference, the values referenced by * the values array are themselves palloc'd. The palloc'd stuff can be * freed by calling free_attstatsslot. + * + * Note: at present, atttype/atttypmod aren't actually used here at all. + * But the caller must have the correct (or at least binary-compatible) + * type ID to pass to free_attstatsslot later. */ bool get_attstatsslot(HeapTuple statstuple, @@ -2478,6 +2482,7 @@ get_attstatsslot(HeapTuple statstuple, Datum val; bool isnull; ArrayType *statarray; + Oid arrayelemtype; int narrayelem; HeapTuple typeTuple; Form_pg_type typeForm; @@ -2503,15 +2508,22 @@ get_attstatsslot(HeapTuple statstuple, elog(ERROR, "stavalues is null"); statarray = DatumGetArrayTypeP(val); - /* Need to get info about the array element type */ - typeTuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(atttype)); + /* + * Need to get info about the array element type. We look at the + * actual element type embedded in the array, which might be only + * binary-compatible with the passed-in atttype. The info we + * extract here should be the same either way, but deconstruct_array + * is picky about having an exact type OID match. + */ + arrayelemtype = ARR_ELEMTYPE(statarray); + typeTuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(arrayelemtype)); if (!HeapTupleIsValid(typeTuple)) - elog(ERROR, "cache lookup failed for type %u", atttype); + elog(ERROR, "cache lookup failed for type %u", arrayelemtype); typeForm = (Form_pg_type) GETSTRUCT(typeTuple); /* Deconstruct array into Datum elements; NULLs not expected */ deconstruct_array(statarray, - atttype, + arrayelemtype, typeForm->typlen, typeForm->typbyval, typeForm->typalign,