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|
----
-- Regression test to Global Temporary Table implementation
--
-- Test for GTT with ON COMMIT DELETE ROWS clause.
--
-- Test drop of GTT when in use throwing error and effective
-- when done in a separate session.
--
----
-- Create a GTT like table to test ON COMMIT DELETE ROWS
CREATE GLOBAL TEMPORARY TABLE t_glob_temptable1 (id integer, lbl text) ON COMMIT DELETE ROWS;
WARNING: GLOBAL is deprecated in temporary table creation
LINE 1: CREATE GLOBAL TEMPORARY TABLE t_glob_temptable1 (id integer,...
^
-- Look at Global Temporary Table definition
SELECT nspname, relname, preserved, code FROM pgtt_schema.pg_global_temp_tables;
nspname | relname | preserved | code
-------------+-------------------+-----------+----------------------
pgtt_schema | t_glob_temptable1 | f | id integer, lbl text
(1 row)
-- A "template" unlogged table should exists
SELECT n.nspname, c.relname FROM pg_class c JOIN pg_namespace n ON (c.relnamespace=n.oid) WHERE relname = 't_glob_temptable1';
nspname | relname
-------------+-------------------
pgtt_schema | t_glob_temptable1
(1 row)
BEGIN;
-- With the first insert some value in the temporary table
INSERT INTO t_glob_temptable1 VALUES (1, 'One');
-- Look if we have two tables now
SELECT regexp_replace(n.nspname, '\d+', 'x', 'g'), c.relname FROM pg_class c JOIN pg_namespace n ON (c.relnamespace=n.oid) WHERE relname = 't_glob_temptable1';
regexp_replace | relname
----------------+-------------------
pgtt_schema | t_glob_temptable1
pg_temp_x | t_glob_temptable1
(2 rows)
-- Second insert, the temporary table exists
INSERT INTO t_glob_temptable1 VALUES (2, 'Two');
-- Look at content of the template for Global Temporary Table, must be empty
SET pgtt.enabled TO off;
SELECT * FROM pgtt_schema.t_glob_temptable1;
id | lbl
----+-----
(0 rows)
SET pgtt.enabled TO on;
-- Look at content of the Global Temporary Table
SELECT * FROM t_glob_temptable1;
id | lbl
----+-----
1 | One
2 | Two
(2 rows)
COMMIT;
-- No row must perstist after the commit
SELECT * FROM t_glob_temptable1;
id | lbl
----+-----
(0 rows)
-- With holdabe cursor the rows must remain
BEGIN;
INSERT INTO t_glob_temptable1 VALUES (1, 'One');
INSERT INTO t_glob_temptable1 VALUES (2, 'Two');
DECLARE curs1 CURSOR WITH HOLD FOR SELECT * FROM t_glob_temptable1;
FETCH curs1;
id | lbl
----+-----
1 | One
(1 row)
COMMIT;
-- No row must perstist after the commit for the cursor
FETCH curs1;
id | lbl
----+-----
2 | Two
(1 row)
-- But not for a new select
SELECT * FROM t_glob_temptable1;
id | lbl
----+-----
(0 rows)
CLOSE curs1;
-- Drop the global temporary table: fail because it is in use
DROP TABLE t_glob_temptable1;
ERROR: can not drop a GTT that is in use.
-- Reconnect and drop it
\c - -
SHOW search_path;
search_path
------------------------------
"$user", public, pgtt_schema
(1 row)
DROP TABLE t_glob_temptable1;
VACUUM pg_class;
SELECT pg_sleep(1);
pg_sleep
----------
(1 row)
-- Look at Global Temporary Table definition
SELECT nspname, relname, preserved, code FROM pgtt_schema.pg_global_temp_tables; -- should be empty
nspname | relname | preserved | code
---------+---------+-----------+------
(0 rows)
-- The "template" unlogged table should not exists anymore
SELECT n.nspname, c.relname FROM pg_class c JOIN pg_namespace n ON (c.relnamespace=n.oid) WHERE relname = 't_glob_temptable1';
nspname | relname
---------+---------
(0 rows)
|
