-- Test functions for copying intermediate results CREATE SCHEMA intermediate_results; SET search_path TO 'intermediate_results'; -- in the same transaction we can read a result BEGIN; SELECT create_intermediate_result('squares', 'SELECT s, s*s FROM generate_series(1,5) s'); create_intermediate_result ---------------------------- 5 (1 row) SELECT * FROM read_intermediate_result('squares', 'binary') AS res (x int, x2 int); x | x2 ---+---- 1 | 1 2 | 4 3 | 9 4 | 16 5 | 25 (5 rows) COMMIT; -- in separate transactions, the result is no longer available SELECT create_intermediate_result('squares', 'SELECT s, s*s FROM generate_series(1,5) s'); create_intermediate_result ---------------------------- 5 (1 row) SELECT * FROM read_intermediate_result('squares', 'binary') AS res (x int, x2 int); ERROR: result "squares" does not exist BEGIN; CREATE TABLE interesting_squares (user_id text, interested_in text); SELECT create_distributed_table('interesting_squares', 'user_id'); create_distributed_table -------------------------- (1 row) INSERT INTO interesting_squares VALUES ('jon', '2'), ('jon', '5'), ('jack', '3'); -- put an intermediate result on all workers SELECT broadcast_intermediate_result('squares', 'SELECT s, s*s FROM generate_series(1,5) s'); broadcast_intermediate_result ------------------------------- 5 (1 row) -- query the intermediate result in a router query SELECT x, x2 FROM interesting_squares JOIN (SELECT * FROM read_intermediate_result('squares', 'binary') AS res (x int, x2 int)) squares ON (x::text = interested_in) WHERE user_id = 'jon' ORDER BY x; x | x2 ---+---- 2 | 4 5 | 25 (2 rows) END; BEGIN; -- put an intermediate result on all workers SELECT broadcast_intermediate_result('squares', 'SELECT s, s*s FROM generate_series(1,5) s'); broadcast_intermediate_result ------------------------------- 5 (1 row) -- query the intermediate result in a distributed query SELECT x, x2 FROM interesting_squares JOIN (SELECT * FROM read_intermediate_result('squares', 'binary') AS res (x int, x2 int)) squares ON (x::text = interested_in) ORDER BY x; x | x2 ---+---- 2 | 4 3 | 9 5 | 25 (3 rows) END; CREATE FUNCTION raise_failed_execution_int_result(query text) RETURNS void AS $$ BEGIN EXECUTE query; EXCEPTION WHEN OTHERS THEN IF SQLERRM LIKE '%does not exist%' THEN RAISE 'Task failed to execute'; ELSIF SQLERRM LIKE '%could not receive query results%' THEN RAISE 'Task failed to execute'; END IF; END; $$LANGUAGE plpgsql; -- don't print the worker port \set VERBOSITY terse SET client_min_messages TO ERROR; -- files should now be cleaned up SELECT raise_failed_execution_int_result($$ SELECT x, x2 FROM interesting_squares JOIN (SELECT * FROM read_intermediate_result('squares', 'binary') AS res (x text, x2 int)) squares ON (x = interested_in) WHERE user_id = 'jon' ORDER BY x; $$); ERROR: Task failed to execute \set VERBOSITY DEFAULT SET client_min_messages TO DEFAULT; -- try to read the file as text, will fail because of binary encoding BEGIN; SELECT create_intermediate_result('squares', 'SELECT s, s*s FROM generate_series(1,5) s'); create_intermediate_result ---------------------------- 5 (1 row) SELECT * FROM read_intermediate_result('squares', 'binary') AS res (x text, x2 int); ERROR: invalid byte sequence for encoding "UTF8": 0x00 END; -- try to read the file with wrong encoding BEGIN; SELECT create_intermediate_result('squares', 'SELECT s, s*s FROM generate_series(1,5) s'); create_intermediate_result ---------------------------- 5 (1 row) SELECT * FROM read_intermediate_result('squares', 'csv') AS res (x int, x2 int); ERROR: invalid input syntax for type integer: "PGCOPY" END; -- try a composite type CREATE TYPE intermediate_results.square_type AS (x text, x2 int); CREATE TABLE stored_squares (user_id text, square intermediate_results.square_type, metadata jsonb); INSERT INTO stored_squares VALUES ('jon', '(2,4)'::intermediate_results.square_type, '{"value":2}'); INSERT INTO stored_squares VALUES ('jon', '(3,9)'::intermediate_results.square_type, '{"value":3}'); INSERT INTO stored_squares VALUES ('jon', '(4,16)'::intermediate_results.square_type, '{"value":4}'); INSERT INTO stored_squares VALUES ('jon', '(5,25)'::intermediate_results.square_type, '{"value":5}'); -- composite types change the format to text BEGIN; SELECT create_intermediate_result('stored_squares', 'SELECT square FROM stored_squares'); create_intermediate_result ---------------------------- 4 (1 row) SELECT * FROM read_intermediate_result('stored_squares', 'binary') AS res (s intermediate_results.square_type); ERROR: COPY file signature not recognized COMMIT; BEGIN; SELECT create_intermediate_result('stored_squares', 'SELECT square FROM stored_squares'); create_intermediate_result ---------------------------- 4 (1 row) SELECT * FROM read_intermediate_result('stored_squares', 'text') AS res (s intermediate_results.square_type); s -------- (2,4) (3,9) (4,16) (5,25) (4 rows) COMMIT; BEGIN; -- put an intermediate result in text format on all workers SELECT broadcast_intermediate_result('stored_squares', 'SELECT square, metadata FROM stored_squares'); broadcast_intermediate_result ------------------------------- 4 (1 row) -- query the intermediate result in a router query using text format SELECT * FROM interesting_squares JOIN ( SELECT * FROM read_intermediate_result('stored_squares', 'text') AS res (s intermediate_results.square_type, m jsonb) ) squares ON ((s).x = interested_in) WHERE user_id = 'jon' ORDER BY 1,2; user_id | interested_in | s | m ---------+---------------+--------+-------------- jon | 2 | (2,4) | {"value": 2} jon | 5 | (5,25) | {"value": 5} (2 rows) -- query the intermediate result in a real-time query using text format SELECT * FROM interesting_squares JOIN ( SELECT * FROM read_intermediate_result('stored_squares', 'text') AS res (s intermediate_results.square_type, m jsonb) ) squares ON ((s).x = interested_in) ORDER BY 1,2; user_id | interested_in | s | m ---------+---------------+--------+-------------- jack | 3 | (3,9) | {"value": 3} jon | 2 | (2,4) | {"value": 2} jon | 5 | (5,25) | {"value": 5} (3 rows) END; BEGIN; -- accurate row count estimates for primitive types SELECT create_intermediate_result('squares', 'SELECT s, s*s FROM generate_series(1,632) s'); create_intermediate_result ---------------------------- 632 (1 row) EXPLAIN (COSTS OFF) SELECT * FROM read_intermediate_result('squares', 'binary') AS res (x int, x2 int); QUERY PLAN ----------------------------------------------- Function Scan on read_intermediate_result res (1 row) -- less accurate results for variable types SELECT create_intermediate_result('hellos', $$SELECT s, 'hello-'||s FROM generate_series(1,63) s$$); create_intermediate_result ---------------------------- 63 (1 row) EXPLAIN (COSTS OFF) SELECT * FROM read_intermediate_result('hellos', 'binary') AS res (x int, y text); QUERY PLAN ----------------------------------------------- Function Scan on read_intermediate_result res (1 row) -- not very accurate results for text encoding SELECT create_intermediate_result('stored_squares', 'SELECT square FROM stored_squares'); create_intermediate_result ---------------------------- 4 (1 row) EXPLAIN (COSTS OFF) SELECT * FROM read_intermediate_result('stored_squares', 'text') AS res (s intermediate_results.square_type); QUERY PLAN ----------------------------------------------- Function Scan on read_intermediate_result res (1 row) END; -- pipe query output into a result file and create a table to check the result COPY (SELECT s, s*s FROM generate_series(1,5) s) TO PROGRAM $$psql -h localhost -p 57636 -U postgres -d regression -c "BEGIN; COPY squares FROM STDIN WITH (format result); CREATE TABLE intermediate_results.squares AS SELECT * FROM read_intermediate_result('squares', 'text') AS res(x int, x2 int); END;"$$ WITH (FORMAT text); SELECT * FROM squares ORDER BY x; x | x2 ---+---- 1 | 1 2 | 4 3 | 9 4 | 16 5 | 25 (5 rows) -- empty shard interval array should raise error SELECT worker_hash_partition_table(42,1,'SELECT a FROM generate_series(1,100) AS a', 'a', 23, ARRAY[0]); ERROR: invalid distribution column value -- cannot use DDL commands select broadcast_intermediate_result('a', 'create table foo(int serial)'); ERROR: cannot execute utility commands select broadcast_intermediate_result('a', 'prepare foo as select 1'); ERROR: cannot execute utility commands select create_intermediate_result('a', 'create table foo(int serial)'); ERROR: cannot execute utility commands -- -- read_intermediate_results -- BEGIN; SELECT create_intermediate_result('squares_1', 'SELECT s, s*s FROM generate_series(1,3) s'), create_intermediate_result('squares_2', 'SELECT s, s*s FROM generate_series(4,6) s'), create_intermediate_result('squares_3', 'SELECT s, s*s FROM generate_series(7,10) s'); create_intermediate_result | create_intermediate_result | create_intermediate_result ----------------------------+----------------------------+---------------------------- 3 | 3 | 4 (1 row) SELECT count(*) FROM read_intermediate_results(ARRAY[]::text[], 'binary') AS res (x int, x2 int); count ------- 0 (1 row) SELECT * FROM read_intermediate_results(ARRAY['squares_1']::text[], 'binary') AS res (x int, x2 int); x | x2 ---+---- 1 | 1 2 | 4 3 | 9 (3 rows) SELECT * FROM read_intermediate_results(ARRAY['squares_1', 'squares_2', 'squares_3']::text[], 'binary') AS res (x int, x2 int); x | x2 ----+----- 1 | 1 2 | 4 3 | 9 4 | 16 5 | 25 6 | 36 7 | 49 8 | 64 9 | 81 10 | 100 (10 rows) COMMIT; -- in separate transactions, the result is no longer available SELECT create_intermediate_result('squares_1', 'SELECT s, s*s FROM generate_series(1,5) s'); create_intermediate_result ---------------------------- 5 (1 row) SELECT * FROM read_intermediate_results(ARRAY['squares_1']::text[], 'binary') AS res (x int, x2 int); ERROR: result "squares_1" does not exist -- error behaviour, and also check that results are deleted on rollback BEGIN; SELECT create_intermediate_result('squares_1', 'SELECT s, s*s FROM generate_series(1,3) s'); create_intermediate_result ---------------------------- 3 (1 row) SAVEPOINT s1; SELECT * FROM read_intermediate_results(ARRAY['notexistingfile', 'squares_1'], 'binary') AS res (x int, x2 int); ERROR: result "notexistingfile" does not exist ROLLBACK TO SAVEPOINT s1; SELECT * FROM read_intermediate_results(ARRAY['squares_1', 'notexistingfile'], 'binary') AS res (x int, x2 int); ERROR: result "notexistingfile" does not exist ROLLBACK TO SAVEPOINT s1; SELECT * FROM read_intermediate_results(ARRAY['squares_1', NULL], 'binary') AS res (x int, x2 int); ERROR: null array element not allowed in this context ROLLBACK TO SAVEPOINT s1; -- after rollbacks we should be able to run vail read_intermediate_results still. SELECT count(*) FROM read_intermediate_results(ARRAY['squares_1']::text[], 'binary') AS res (x int, x2 int); count ------- 3 (1 row) SELECT count(*) FROM read_intermediate_results(ARRAY[]::text[], 'binary') AS res (x int, x2 int); count ------- 0 (1 row) END; SELECT * FROM read_intermediate_results(ARRAY['squares_1']::text[], 'binary') AS res (x int, x2 int); ERROR: result "squares_1" does not exist -- Test non-binary format: read_intermediate_results(..., 'text') BEGIN; -- ROW(...) types switch the output format to text SELECT broadcast_intermediate_result('stored_squares_1', 'SELECT s, s*s, ROW(1::text, 2) FROM generate_series(1,3) s'), broadcast_intermediate_result('stored_squares_2', 'SELECT s, s*s, ROW(2::text, 3) FROM generate_series(4,6) s'); broadcast_intermediate_result | broadcast_intermediate_result -------------------------------+------------------------------- 3 | 3 (1 row) -- query the intermediate result in a router query using text format SELECT * FROM interesting_squares JOIN ( SELECT * FROM read_intermediate_results(ARRAY['stored_squares_1', 'stored_squares_2'], 'binary') AS res (x int, x2 int, z intermediate_results.square_type) ) squares ON (squares.x::text = interested_in) WHERE user_id = 'jon' ORDER BY 1,2; user_id | interested_in | x | x2 | z ---------+---------------+---+----+------- jon | 2 | 2 | 4 | (1,2) jon | 5 | 5 | 25 | (2,3) (2 rows) END; DROP SCHEMA intermediate_results CASCADE; NOTICE: drop cascades to 5 other objects DETAIL: drop cascades to table interesting_squares drop cascades to function raise_failed_execution_int_result(text) drop cascades to type square_type drop cascades to table stored_squares drop cascades to table squares