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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)
SELECT pg_create_logical_replication_slot('foo', 'nonexistent');
ERROR: could not access file "nonexistent": No such file or directory
-- 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
-- monitoring functions for slot directories
SELECT count(*) >= 0 AS ok FROM pg_ls_logicalmapdir();
ok
----
t
(1 row)
SELECT count(*) >= 0 AS ok FROM pg_ls_logicalsnapdir();
ok
----
t
(1 row)
SELECT count(*) >= 0 AS ok FROM pg_ls_replslotdir('regression_slot_p');
ok
----
t
(1 row)
SELECT count(*) >= 0 AS ok FROM pg_ls_replslotdir('not_existing_slot'); -- fails
ERROR: replication slot "not_existing_slot" 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
-- slot advance with physical slot, error with non-reserved slot
SELECT slot_name FROM pg_create_physical_replication_slot('regression_slot3');
slot_name
------------------
regression_slot3
(1 row)
SELECT pg_replication_slot_advance('regression_slot3', '0/0'); -- invalid LSN
ERROR: invalid target WAL LSN
SELECT pg_replication_slot_advance('regression_slot3', '0/1'); -- error
ERROR: replication slot "regression_slot3" cannot be advanced
DETAIL: This slot has never previously reserved WAL, or it has been invalidated.
SELECT pg_drop_replication_slot('regression_slot3');
pg_drop_replication_slot
--------------------------
(1 row)
--
-- Test copy functions for logical replication slots
--
-- Create and copy logical slots
SELECT 'init' FROM pg_create_logical_replication_slot('orig_slot1', 'test_decoding', false);
?column?
----------
init
(1 row)
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot1', 'copied_slot1_no_change');
?column?
----------
copy
(1 row)
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot1', 'copied_slot1_change_plugin', false, 'pgoutput');
?column?
----------
copy
(1 row)
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot1', 'copied_slot1_change_plugin_temp', true, 'pgoutput');
?column?
----------
copy
(1 row)
-- Check all copied slots status
SELECT
o.slot_name, o.plugin, o.temporary, c.slot_name, c.plugin, c.temporary
FROM
(SELECT * FROM pg_replication_slots WHERE slot_name LIKE 'orig%') as o
LEFT JOIN pg_replication_slots as c ON o.restart_lsn = c.restart_lsn AND o.confirmed_flush_lsn = c.confirmed_flush_lsn
WHERE
o.slot_name != c.slot_name
ORDER BY o.slot_name, c.slot_name;
slot_name | plugin | temporary | slot_name | plugin | temporary
------------+---------------+-----------+---------------------------------+---------------+-----------
orig_slot1 | test_decoding | f | copied_slot1_change_plugin | pgoutput | f
orig_slot1 | test_decoding | f | copied_slot1_change_plugin_temp | pgoutput | t
orig_slot1 | test_decoding | f | copied_slot1_no_change | test_decoding | f
(3 rows)
-- Now we have maximum 4 replication slots. Check slots are properly
-- released even when raise error during creating the target slot.
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot1', 'failed'); -- error
ERROR: all replication slots are in use
HINT: Free one or increase max_replication_slots.
-- temporary slots were dropped automatically
SELECT pg_drop_replication_slot('orig_slot1');
pg_drop_replication_slot
--------------------------
(1 row)
SELECT pg_drop_replication_slot('copied_slot1_no_change');
pg_drop_replication_slot
--------------------------
(1 row)
SELECT pg_drop_replication_slot('copied_slot1_change_plugin');
pg_drop_replication_slot
--------------------------
(1 row)
-- Test based on the temporary logical slot
SELECT 'init' FROM pg_create_logical_replication_slot('orig_slot2', 'test_decoding', true);
?column?
----------
init
(1 row)
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot2', 'copied_slot2_no_change');
?column?
----------
copy
(1 row)
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot2', 'copied_slot2_change_plugin', true, 'pgoutput');
?column?
----------
copy
(1 row)
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot2', 'copied_slot2_change_plugin_temp', false, 'pgoutput');
?column?
----------
copy
(1 row)
-- Check all copied slots status
SELECT
o.slot_name, o.plugin, o.temporary, c.slot_name, c.plugin, c.temporary
FROM
(SELECT * FROM pg_replication_slots WHERE slot_name LIKE 'orig%') as o
LEFT JOIN pg_replication_slots as c ON o.restart_lsn = c.restart_lsn AND o.confirmed_flush_lsn = c.confirmed_flush_lsn
WHERE
o.slot_name != c.slot_name
ORDER BY o.slot_name, c.slot_name;
slot_name | plugin | temporary | slot_name | plugin | temporary
------------+---------------+-----------+---------------------------------+---------------+-----------
orig_slot2 | test_decoding | t | copied_slot2_change_plugin | pgoutput | t
orig_slot2 | test_decoding | t | copied_slot2_change_plugin_temp | pgoutput | f
orig_slot2 | test_decoding | t | copied_slot2_no_change | test_decoding | t
(3 rows)
-- Cannot copy a logical slot to a physical slot
SELECT 'copy' FROM pg_copy_physical_replication_slot('orig_slot2', 'failed'); -- error
ERROR: cannot copy physical replication slot "orig_slot2" as a logical replication slot
-- temporary slots were dropped automatically
SELECT pg_drop_replication_slot('copied_slot2_change_plugin_temp');
pg_drop_replication_slot
--------------------------
(1 row)
--
-- Test copy functions for physical replication slots
--
-- Create and copy physical slots
SELECT 'init' FROM pg_create_physical_replication_slot('orig_slot1', true);
?column?
----------
init
(1 row)
SELECT 'init' FROM pg_create_physical_replication_slot('orig_slot2', false);
?column?
----------
init
(1 row)
SELECT 'copy' FROM pg_copy_physical_replication_slot('orig_slot1', 'copied_slot1_no_change');
?column?
----------
copy
(1 row)
SELECT 'copy' FROM pg_copy_physical_replication_slot('orig_slot1', 'copied_slot1_temp', true);
?column?
----------
copy
(1 row)
-- Check all copied slots status. Since all slots don't reserve WAL we check only other fields.
SELECT slot_name, slot_type, temporary FROM pg_replication_slots;
slot_name | slot_type | temporary
------------------------+-----------+-----------
orig_slot1 | physical | f
orig_slot2 | physical | f
copied_slot1_no_change | physical | f
copied_slot1_temp | physical | t
(4 rows)
-- Cannot copy a physical slot to a logical slot
SELECT 'copy' FROM pg_copy_logical_replication_slot('orig_slot1', 'failed'); -- error
ERROR: cannot copy logical replication slot "orig_slot1" as a physical replication slot
-- Cannot copy a physical slot that doesn't reserve WAL
SELECT 'copy' FROM pg_copy_physical_replication_slot('orig_slot2', 'failed'); -- error
ERROR: cannot copy a replication slot that doesn't reserve WAL
-- temporary slots were dropped automatically
SELECT pg_drop_replication_slot('orig_slot1');
pg_drop_replication_slot
--------------------------
(1 row)
SELECT pg_drop_replication_slot('orig_slot2');
pg_drop_replication_slot
--------------------------
(1 row)
SELECT pg_drop_replication_slot('copied_slot1_no_change');
pg_drop_replication_slot
--------------------------
(1 row)
-- Test based on the temporary physical slot
SELECT 'init' FROM pg_create_physical_replication_slot('orig_slot2', true, true);
?column?
----------
init
(1 row)
SELECT 'copy' FROM pg_copy_physical_replication_slot('orig_slot2', 'copied_slot2_no_change');
?column?
----------
copy
(1 row)
SELECT 'copy' FROM pg_copy_physical_replication_slot('orig_slot2', 'copied_slot2_notemp', false);
?column?
----------
copy
(1 row)
-- Check all copied slots status
SELECT
o.slot_name, o.temporary, c.slot_name, c.temporary
FROM
(SELECT * FROM pg_replication_slots WHERE slot_name LIKE 'orig%') as o
LEFT JOIN pg_replication_slots as c ON o.restart_lsn = c.restart_lsn
WHERE
o.slot_name != c.slot_name
ORDER BY o.slot_name, c.slot_name;
slot_name | temporary | slot_name | temporary
------------+-----------+------------------------+-----------
orig_slot2 | t | copied_slot2_no_change | t
orig_slot2 | t | copied_slot2_notemp | f
(2 rows)
SELECT pg_drop_replication_slot('orig_slot2');
pg_drop_replication_slot
--------------------------
(1 row)
SELECT pg_drop_replication_slot('copied_slot2_no_change');
pg_drop_replication_slot
--------------------------
(1 row)
SELECT pg_drop_replication_slot('copied_slot2_notemp');
pg_drop_replication_slot
--------------------------
(1 row)
|