# MERGE MATCHED RECHECK # # This test looks at what happens when we have complex # WHEN MATCHED AND conditions and a concurrent UPDATE causes a # recheck of the AND condition on the new row setup { CREATE TABLE target (key int primary key, balance integer, status text, val text); INSERT INTO target VALUES (1, 160, 's1', 'setup'); CREATE TABLE target_pa (key int, balance integer, status text, val text) PARTITION BY RANGE (balance); CREATE TABLE target_pa1 PARTITION OF target_pa FOR VALUES FROM (0) TO (200); CREATE TABLE target_pa2 PARTITION OF target_pa FOR VALUES FROM (200) TO (1000); INSERT INTO target_pa VALUES (1, 160, 's1', 'setup'); CREATE TABLE target_tg (key int primary key, balance integer, status text, val text); CREATE FUNCTION target_tg_trig_fn() RETURNS trigger LANGUAGE plpgsql AS $$ BEGIN IF tg_op = 'INSERT' THEN RAISE NOTICE 'Insert: %', NEW; RETURN NEW; ELSIF tg_op = 'UPDATE' THEN RAISE NOTICE 'Update: % -> %', OLD, NEW; RETURN NEW; ELSE RAISE NOTICE 'Delete: %', OLD; RETURN OLD; END IF; END $$; CREATE TRIGGER target_tg_trig BEFORE INSERT OR UPDATE OR DELETE ON target_tg FOR EACH ROW EXECUTE FUNCTION target_tg_trig_fn(); INSERT INTO target_tg VALUES (1, 160, 's1', 'setup'); } teardown { DROP TABLE target; DROP TABLE target_pa; DROP TABLE target_tg; DROP FUNCTION target_tg_trig_fn; } session "s1" setup { BEGIN ISOLATION LEVEL READ COMMITTED; } step "merge_status" { MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED AND status = 's1' THEN UPDATE SET status = 's2', val = t.val || ' when1' WHEN MATCHED AND status = 's2' THEN UPDATE SET status = 's3', val = t.val || ' when2' WHEN MATCHED AND status = 's3' THEN UPDATE SET status = 's4', val = t.val || ' when3'; } step "merge_status_tg" { MERGE INTO target_tg t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED AND status = 's1' THEN UPDATE SET status = 's2', val = t.val || ' when1' WHEN MATCHED AND status = 's2' THEN UPDATE SET status = 's3', val = t.val || ' when2' WHEN MATCHED AND status = 's3' THEN UPDATE SET status = 's4', val = t.val || ' when3'; } step "merge_bal" { MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED AND balance < 100 THEN UPDATE SET balance = balance * 2, val = t.val || ' when1' WHEN MATCHED AND balance < 200 THEN UPDATE SET balance = balance * 4, val = t.val || ' when2' WHEN MATCHED AND balance < 300 THEN UPDATE SET balance = balance * 8, val = t.val || ' when3'; } step "merge_bal_pa" { MERGE INTO target_pa t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED AND balance < 100 THEN UPDATE SET balance = balance * 2, val = t.val || ' when1' WHEN MATCHED AND balance < 200 THEN UPDATE SET balance = balance * 4, val = t.val || ' when2' WHEN MATCHED AND balance < 300 THEN UPDATE SET balance = balance * 8, val = t.val || ' when3'; } step "merge_bal_tg" { MERGE INTO target_tg t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED AND balance < 100 THEN UPDATE SET balance = balance * 2, val = t.val || ' when1' WHEN MATCHED AND balance < 200 THEN UPDATE SET balance = balance * 4, val = t.val || ' when2' WHEN MATCHED AND balance < 300 THEN UPDATE SET balance = balance * 8, val = t.val || ' when3'; } step "merge_delete" { MERGE INTO target t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED AND balance < 100 THEN UPDATE SET balance = balance * 2, val = t.val || ' when1' WHEN MATCHED AND balance < 200 THEN DELETE; } step "merge_delete_tg" { MERGE INTO target_tg t USING (SELECT 1 as key) s ON s.key = t.key WHEN MATCHED AND balance < 100 THEN UPDATE SET balance = balance * 2, val = t.val || ' when1' WHEN MATCHED AND balance < 200 THEN DELETE; } step "select1" { SELECT * FROM target; } step "select1_pa" { SELECT * FROM target_pa; } step "select1_tg" { SELECT * FROM target_tg; } step "c1" { COMMIT; } session "s2" setup { BEGIN ISOLATION LEVEL READ COMMITTED; } step "update1" { UPDATE target t SET balance = balance + 10, val = t.val || ' updated by update1' WHERE t.key = 1; } step "update1_tg" { UPDATE target_tg t SET balance = balance + 10, val = t.val || ' updated by update1_tg' WHERE t.key = 1; } step "update2" { UPDATE target t SET status = 's2', val = t.val || ' updated by update2' WHERE t.key = 1; } step "update2_tg" { UPDATE target_tg t SET status = 's2', val = t.val || ' updated by update2_tg' WHERE t.key = 1; } step "update3" { UPDATE target t SET status = 's3', val = t.val || ' updated by update3' WHERE t.key = 1; } step "update3_tg" { UPDATE target_tg t SET status = 's3', val = t.val || ' updated by update3_tg' WHERE t.key = 1; } step "update5" { UPDATE target t SET status = 's5', val = t.val || ' updated by update5' WHERE t.key = 1; } step "update5_tg" { UPDATE target_tg t SET status = 's5', val = t.val || ' updated by update5_tg' WHERE t.key = 1; } step "update_bal1" { UPDATE target t SET balance = 50, val = t.val || ' updated by update_bal1' WHERE t.key = 1; } step "update_bal1_pa" { UPDATE target_pa t SET balance = 50, val = t.val || ' updated by update_bal1_pa' WHERE t.key = 1; } step "update_bal1_tg" { UPDATE target_tg t SET balance = 50, val = t.val || ' updated by update_bal1_tg' WHERE t.key = 1; } step "c2" { COMMIT; } # merge_status sees concurrently updated row and rechecks WHEN conditions, but recheck passes and final status = 's2' permutation "update1" "merge_status" "c2" "select1" "c1" permutation "update1_tg" "merge_status_tg" "c2" "select1_tg" "c1" # merge_status sees concurrently updated row and rechecks WHEN conditions, recheck fails, so final status = 's3' not 's2' permutation "update2" "merge_status" "c2" "select1" "c1" permutation "update2_tg" "merge_status_tg" "c2" "select1_tg" "c1" # merge_status sees concurrently updated row and rechecks WHEN conditions, recheck fails, so final status = 's4' not 's2' permutation "update3" "merge_status" "c2" "select1" "c1" permutation "update3_tg" "merge_status_tg" "c2" "select1_tg" "c1" # merge_status sees concurrently updated row and rechecks WHEN conditions, recheck fails, but we skip update and MERGE does nothing permutation "update5" "merge_status" "c2" "select1" "c1" permutation "update5_tg" "merge_status_tg" "c2" "select1_tg" "c1" # merge_bal sees concurrently updated row and rechecks WHEN conditions, recheck fails, so final balance = 100 not 640 permutation "update_bal1" "merge_bal" "c2" "select1" "c1" permutation "update_bal1_pa" "merge_bal_pa" "c2" "select1_pa" "c1" permutation "update_bal1_tg" "merge_bal_tg" "c2" "select1_tg" "c1" # merge_delete sees concurrently updated row and rechecks WHEN conditions, but recheck passes and row is deleted permutation "update1" "merge_delete" "c2" "select1" "c1" permutation "update1_tg" "merge_delete_tg" "c2" "select1_tg" "c1" # merge_delete sees concurrently updated row and rechecks WHEN conditions, recheck fails, so final balance is 100 permutation "update_bal1" "merge_delete" "c2" "select1" "c1" permutation "update_bal1_tg" "merge_delete_tg" "c2" "select1_tg" "c1"