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-- test that we can insert the result of a get_changes call into a
-- logged relation. That's really not a good idea in practical terms,
-- but provides a nice test.
-- predictability
SET synchronous_commit = on;
SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot', 'test_decoding');
?column?
----------
init
(1 row)
-- slot works
SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data
------
(0 rows)
-- create some changes
CREATE TABLE somechange(id serial primary key);
INSERT INTO somechange DEFAULT VALUES;
CREATE TABLE changeresult AS
SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
SELECT * FROM changeresult;
data
------------------------------------------------
BEGIN
table public.somechange: INSERT: id[integer]:1
COMMIT
(3 rows)
INSERT INTO changeresult
SELECT data FROM pg_logical_slot_peek_changes('regression_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
INSERT INTO changeresult
SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
SELECT * FROM changeresult;
data
--------------------------------------------------------------------------------------------------------------------------------------------------
BEGIN
table public.somechange: INSERT: id[integer]:1
COMMIT
BEGIN
table public.changeresult: INSERT: data[text]:'BEGIN'
table public.changeresult: INSERT: data[text]:'table public.somechange: INSERT: id[integer]:1'
table public.changeresult: INSERT: data[text]:'COMMIT'
COMMIT
BEGIN
table public.changeresult: INSERT: data[text]:'BEGIN'
table public.changeresult: INSERT: data[text]:'table public.somechange: INSERT: id[integer]:1'
table public.changeresult: INSERT: data[text]:'COMMIT'
COMMIT
BEGIN
table public.changeresult: INSERT: data[text]:'BEGIN'
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''BEGIN'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.somechange: INSERT: id[integer]:1'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''COMMIT'''
table public.changeresult: INSERT: data[text]:'COMMIT'
COMMIT
(20 rows)
DROP TABLE changeresult;
DROP TABLE somechange;
-- check calling logical decoding from pl/pgsql
CREATE FUNCTION slot_changes_wrapper(slot_name name) RETURNS SETOF TEXT AS $$
BEGIN
RETURN QUERY
SELECT data FROM pg_logical_slot_peek_changes(slot_name, NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
END$$ LANGUAGE plpgsql;
SELECT * FROM slot_changes_wrapper('regression_slot');
slot_changes_wrapper
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
BEGIN
table public.changeresult: INSERT: data[text]:'BEGIN'
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''BEGIN'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.somechange: INSERT: id[integer]:1'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''COMMIT'''
table public.changeresult: INSERT: data[text]:'COMMIT'
table public.changeresult: INSERT: data[text]:'BEGIN'
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''BEGIN'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.changeresult: INSERT: data[text]:''''BEGIN'''''''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.changeresult: INSERT: data[text]:''''table public.somechange: INSERT: id[integer]:1'''''''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.changeresult: INSERT: data[text]:''''COMMIT'''''''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''COMMIT'''
table public.changeresult: INSERT: data[text]:'COMMIT'
COMMIT
(14 rows)
SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
data
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
BEGIN
table public.changeresult: INSERT: data[text]:'BEGIN'
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''BEGIN'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.somechange: INSERT: id[integer]:1'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''COMMIT'''
table public.changeresult: INSERT: data[text]:'COMMIT'
table public.changeresult: INSERT: data[text]:'BEGIN'
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''BEGIN'''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.changeresult: INSERT: data[text]:''''BEGIN'''''''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.changeresult: INSERT: data[text]:''''table public.somechange: INSERT: id[integer]:1'''''''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''table public.changeresult: INSERT: data[text]:''''COMMIT'''''''
table public.changeresult: INSERT: data[text]:'table public.changeresult: INSERT: data[text]:''COMMIT'''
table public.changeresult: INSERT: data[text]:'COMMIT'
COMMIT
(14 rows)
SELECT 'stop' FROM pg_drop_replication_slot('regression_slot');
?column?
----------
stop
(1 row)
|
