Re: Bug in RETURN QUERY

Hello

2008/9/1 Oleg Serov <serovov(at)gmail(dot)com>:
> Hello all SQL BUG CODE:
> BEGIN;
> SELECT version(); -- "PostgreSQL 8.3.3 on i686-redhat-linux-gnu, compiled by
> GCC gcc (GCC) 4.1.2 20070626 (Red Hat 4.1.2-14)"
> CREATE TYPE "buggy_enum_first" AS ENUM ( 'bug1', 'bug2', 'bug3' );
>
> CREATE TABLE "bug_table" (
> "id" BIGINT NOT NULL,
> "buggy_enum_field" "buggy_enum_first" DEFAULT 'bug1'::buggy_enum_first NOT
> NULL,
> CONSTRAINT "test_table_pkey" PRIMARY KEY("id")
> ) WITHOUT OIDS;
>
>
> CREATE FUNCTION buggy_procedure() RETURNS SETOF bug_table
> AS $$
> BEGIN
> -- @todo hide password
> RETURN QUERY (
> SELECT *
> FROM bug_table
> );
> END;
> $$
> LANGUAGE plpgsql STRICT SECURITY DEFINER;
>
> SELECT * FROM buggy_procedure(); -- All Okey
> DROP TYPE buggy_enum_first CASCADE;
> CREATE TYPE "buggy_enum_second" AS ENUM ( 'bug1', 'bug2', 'bug3' );
> ALTER TABLE bug_table ADD COLUMN buggy_enum_field buggy_enum_second;
> SELECT * FROM buggy_procedure(); -- Bug
> ROLLBACK;
> /*NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index
> "test_table_pkey" for table "bug_table"
>
> NOTICE: drop cascades to default for table bug_table column
> buggy_enum_fieldNOTICE: drop cascades to table bug_table column
> buggy_enum_field
> ERROR: structure of query does not match function result type
> CONTEXT: PL/pgSQL function "buggy_procedure" line 3 at RETURN QUERY*/

this isn't bug, it's feature. Informations stored in execution plan
are broken, when some references to removed objects are stored in plan
- objects aren't stored by name, but by object id. So, when you drop
any object, then you have to finish session. Note: actually only drop
of table emits plan cache invalidation signal.

Regards
Pavel Stehule