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--
-- DMLs on test table
--
SET pg_stat_statements.track_utility = FALSE;
CREATE TEMP TABLE pgss_dml_tab (a int, b char(20));
INSERT INTO pgss_dml_tab VALUES(generate_series(1, 10), 'aaa');
UPDATE pgss_dml_tab SET b = 'bbb' WHERE a > 7;
DELETE FROM pgss_dml_tab WHERE a > 9;
-- explicit transaction
BEGIN;
UPDATE pgss_dml_tab SET b = '111' WHERE a = 1 ;
COMMIT;
BEGIN \;
UPDATE pgss_dml_tab SET b = '222' WHERE a = 2 \;
COMMIT ;
UPDATE pgss_dml_tab SET b = '333' WHERE a = 3 \;
UPDATE pgss_dml_tab SET b = '444' WHERE a = 4 ;
BEGIN \;
UPDATE pgss_dml_tab SET b = '555' WHERE a = 5 \;
UPDATE pgss_dml_tab SET b = '666' WHERE a = 6 \;
COMMIT ;
-- many INSERT values
INSERT INTO pgss_dml_tab (a, b) VALUES (1, 'a'), (2, 'b'), (3, 'c');
-- SELECT with constants
SELECT * FROM pgss_dml_tab WHERE a > 5 ORDER BY a ;
a | b
---+----------------------
6 | 666
7 | aaa
8 | bbb
9 | bbb
(4 rows)
SELECT *
FROM pgss_dml_tab
WHERE a > 9
ORDER BY a ;
a | b
---+---
(0 rows)
-- these two need to be done on a different table
-- SELECT without constants
SELECT * FROM pgss_dml_tab ORDER BY a;
a | b
---+----------------------
1 | a
1 | 111
2 | b
2 | 222
3 | c
3 | 333
4 | 444
5 | 555
6 | 666
7 | aaa
8 | bbb
9 | bbb
(12 rows)
-- SELECT with IN clause
SELECT * FROM pgss_dml_tab WHERE a IN (1, 2, 3, 4, 5);
a | b
---+----------------------
1 | 111
2 | 222
3 | 333
4 | 444
5 | 555
1 | a
2 | b
3 | c
(8 rows)
SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
calls | rows | query
-------+------+---------------------------------------------------------------------
1 | 1 | DELETE FROM pgss_dml_tab WHERE a > $1
1 | 3 | INSERT INTO pgss_dml_tab (a, b) VALUES ($1, $2), ($3, $4), ($5, $6)
1 | 10 | INSERT INTO pgss_dml_tab VALUES(generate_series($1, $2), $3)
1 | 12 | SELECT * FROM pgss_dml_tab ORDER BY a
2 | 4 | SELECT * FROM pgss_dml_tab WHERE a > $1 ORDER BY a
1 | 8 | SELECT * FROM pgss_dml_tab WHERE a IN ($1, $2, $3, $4, $5)
1 | 1 | SELECT pg_stat_statements_reset()
1 | 0 | SET pg_stat_statements.track_utility = FALSE
6 | 6 | UPDATE pgss_dml_tab SET b = $1 WHERE a = $2
1 | 3 | UPDATE pgss_dml_tab SET b = $1 WHERE a > $2
(10 rows)
SELECT pg_stat_statements_reset();
pg_stat_statements_reset
--------------------------
(1 row)
-- MERGE
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= 4)
WHEN MATCHED THEN UPDATE SET b = st.b || st.a::text;
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= 4)
WHEN MATCHED THEN UPDATE SET b = pgss_dml_tab.b || st.a::text;
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= 4)
WHEN MATCHED AND length(st.b) > 1 THEN UPDATE SET b = pgss_dml_tab.b || st.a::text;
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a)
WHEN NOT MATCHED THEN INSERT (a, b) VALUES (0, NULL);
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a)
WHEN NOT MATCHED THEN INSERT VALUES (0, NULL); -- same as above
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a)
WHEN NOT MATCHED THEN INSERT (b, a) VALUES (NULL, 0);
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a)
WHEN NOT MATCHED THEN INSERT (a) VALUES (0);
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= 4)
WHEN MATCHED THEN DELETE;
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= 4)
WHEN MATCHED THEN DO NOTHING;
MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= 4)
WHEN NOT MATCHED THEN DO NOTHING;
DROP TABLE pgss_dml_tab;
SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
calls | rows | query
-------+------+-----------------------------------------------------------------------------------------
1 | 6 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= $1)+
| | WHEN MATCHED AND length(st.b) > $2 THEN UPDATE SET b = pgss_dml_tab.b || st.a::text
1 | 6 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= $1)+
| | WHEN MATCHED THEN DELETE
1 | 0 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= $1)+
| | WHEN MATCHED THEN DO NOTHING
1 | 6 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= $1)+
| | WHEN MATCHED THEN UPDATE SET b = pgss_dml_tab.b || st.a::text
1 | 6 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= $1)+
| | WHEN MATCHED THEN UPDATE SET b = st.b || st.a::text
1 | 0 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a AND st.a >= $1)+
| | WHEN NOT MATCHED THEN DO NOTHING
1 | 0 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a) +
| | WHEN NOT MATCHED THEN INSERT (a) VALUES ($1)
2 | 0 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a) +
| | WHEN NOT MATCHED THEN INSERT (a, b) VALUES ($1, $2)
1 | 0 | MERGE INTO pgss_dml_tab USING pgss_dml_tab st ON (st.a = pgss_dml_tab.a) +
| | WHEN NOT MATCHED THEN INSERT (b, a) VALUES ($1, $2)
1 | 1 | SELECT pg_stat_statements_reset()
(10 rows)
-- check that [temp] table relation extensions are tracked as writes
CREATE TABLE pgss_extend_tab (a int, b text);
CREATE TEMP TABLE pgss_extend_temp_tab (a int, b text);
SELECT pg_stat_statements_reset();
pg_stat_statements_reset
--------------------------
(1 row)
INSERT INTO pgss_extend_tab (a, b) SELECT generate_series(1, 1000), 'something';
INSERT INTO pgss_extend_temp_tab (a, b) SELECT generate_series(1, 1000), 'something';
WITH sizes AS (
SELECT
pg_relation_size('pgss_extend_tab') / current_setting('block_size')::int8 AS rel_size,
pg_relation_size('pgss_extend_temp_tab') / current_setting('block_size')::int8 AS temp_rel_size
)
SELECT
SUM(local_blks_written) >= (SELECT temp_rel_size FROM sizes) AS temp_written_ok,
SUM(local_blks_dirtied) >= (SELECT temp_rel_size FROM sizes) AS temp_dirtied_ok,
SUM(shared_blks_written) >= (SELECT rel_size FROM sizes) AS written_ok,
SUM(shared_blks_dirtied) >= (SELECT rel_size FROM sizes) AS dirtied_ok
FROM pg_stat_statements;
temp_written_ok | temp_dirtied_ok | written_ok | dirtied_ok
-----------------+-----------------+------------+------------
t | t | t | t
(1 row)
SELECT pg_stat_statements_reset();
pg_stat_statements_reset
--------------------------
(1 row)
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