File: ut-T.sql

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pg-hint-plan-18 1.8.0-3
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-- ut-T: tests for table hints
-- This test is focusing on hint retrieval from table

LOAD 'pg_hint_plan';
SET pg_hint_plan.enable_hint TO on;
SET pg_hint_plan.debug_print TO on;
SET client_min_messages TO LOG;
SET search_path TO public;

-- This hint affects queries with an equivalent query ID when executed as
-- a subquery.
SET pg_hint_plan.enable_hint_table TO on;
SELECT get_query_id('SELECT * FROM t1 WHERE id = 1;') AS query_id \gset
INSERT INTO hint_plan.hints VALUES (DEFAULT, :'query_id', '', 'SeqScan(t1)');

PREPARE p1 AS SELECT * FROM t1 WHERE id = 100;

-- These queries uses IndexScan without hints
SET pg_hint_plan.enable_hint_table to off;
EXPLAIN (COSTS false) SELECT * FROM t1 WHERE id = 100;
EXPLAIN (COSTS false) EXECUTE p1;
DEALLOCATE p1;
PREPARE p1 AS SELECT * FROM t1 WHERE id = 100;
EXPLAIN (COSTS false) CREATE TABLE ct1 AS EXECUTE p1;

DEALLOCATE p1;
PREPARE p1 AS SELECT * FROM t1 WHERE id = 100;

-- Forced to use SeqScan by table hints
SET pg_hint_plan.enable_hint_table to on;
EXPLAIN (COSTS false) SELECT * FROM t1 WHERE id = 100;
EXPLAIN (COSTS false) EXECUTE p1;
DEALLOCATE p1;
PREPARE p1 AS SELECT * FROM t1 WHERE id = 100;
EXPLAIN (COSTS false) CREATE TABLE ct1 AS EXECUTE p1;

DEALLOCATE p1;

SET pg_hint_plan.enable_hint_table to off;
DELETE FROM hint_plan.hints;