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|
-- predictability
SET synchronous_commit = on;
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot_p', 'test_decoding');
?column?
----------
init
(1 row)
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot_t', 'test_decoding', true);
?column?
----------
init
(1 row)
SELECT pg_drop_replication_slot('regression_slot_p');
pg_drop_replication_slot
--------------------------
(1 row)
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot_p', 'test_decoding', false);
?column?
----------
init
(1 row)
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot_t2', 'test_decoding', true);
?column?
----------
init
(1 row)
-- here we want to start a new session and wait till old one is gone
select pg_backend_pid() as oldpid \gset
\c -
SET synchronous_commit = on;
do 'declare c int = 0;
begin
while (select count(*) from pg_replication_slots where active_pid = '
:'oldpid'
') > 0 loop c := c + 1; perform pg_sleep(0.01); end loop;
raise log ''slot test looped % times'', c;
end';
-- should fail because the temporary slots were dropped automatically
SELECT pg_drop_replication_slot('regression_slot_t');
ERROR: replication slot "regression_slot_t" does not exist
SELECT pg_drop_replication_slot('regression_slot_t2');
ERROR: replication slot "regression_slot_t2" does not exist
-- permanent slot has survived
SELECT pg_drop_replication_slot('regression_slot_p');
pg_drop_replication_slot
--------------------------
(1 row)
-- test switching between slots in a session
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot1', 'test_decoding', true);
?column?
----------
init
(1 row)
CREATE TABLE replication_example(id SERIAL PRIMARY KEY, somedata int, text varchar(120));
BEGIN;
INSERT INTO replication_example(somedata, text) VALUES (1, 1);
INSERT INTO replication_example(somedata, text) VALUES (1, 2);
COMMIT;
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot2', 'test_decoding', true);
?column?
----------
init
(1 row)
INSERT INTO replication_example(somedata, text) VALUES (1, 3);
SELECT data FROM pg_logical_slot_get_changes('regression_slot1', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data
---------------------------------------------------------------------------------------------------------
BEGIN
table public.replication_example: INSERT: id[integer]:1 somedata[integer]:1 text[character varying]:'1'
table public.replication_example: INSERT: id[integer]:2 somedata[integer]:1 text[character varying]:'2'
COMMIT
BEGIN
table public.replication_example: INSERT: id[integer]:3 somedata[integer]:1 text[character varying]:'3'
COMMIT
(7 rows)
SELECT data FROM pg_logical_slot_get_changes('regression_slot2', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data
---------------------------------------------------------------------------------------------------------
BEGIN
table public.replication_example: INSERT: id[integer]:3 somedata[integer]:1 text[character varying]:'3'
COMMIT
(3 rows)
INSERT INTO replication_example(somedata, text) VALUES (1, 4);
INSERT INTO replication_example(somedata, text) VALUES (1, 5);
SELECT pg_current_wal_lsn() AS wal_lsn \gset
INSERT INTO replication_example(somedata, text) VALUES (1, 6);
SELECT end_lsn FROM pg_replication_slot_advance('regression_slot1', :'wal_lsn') \gset
SELECT slot_name FROM pg_replication_slot_advance('regression_slot2', pg_current_wal_lsn());
slot_name
------------------
regression_slot2
(1 row)
SELECT :'wal_lsn' = :'end_lsn';
?column?
----------
t
(1 row)
SELECT data FROM pg_logical_slot_get_changes('regression_slot1', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data
---------------------------------------------------------------------------------------------------------
BEGIN
table public.replication_example: INSERT: id[integer]:6 somedata[integer]:1 text[character varying]:'6'
COMMIT
(3 rows)
SELECT data FROM pg_logical_slot_get_changes('regression_slot2', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data
------
(0 rows)
DROP TABLE replication_example;
-- error
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot1', 'test_decoding', true);
ERROR: replication slot "regression_slot1" already exists
-- both should error as they should be dropped on error
SELECT pg_drop_replication_slot('regression_slot1');
ERROR: replication slot "regression_slot1" does not exist
SELECT pg_drop_replication_slot('regression_slot2');
ERROR: replication slot "regression_slot2" does not exist
|