# MERGE INSERT UPDATE # # This looks at how we handle concurrent INSERTs, illustrating how the # behavior differs from INSERT ... ON CONFLICT setup { CREATE TABLE target (key int primary key, val text); } teardown { DROP TABLE target; } session "s1" setup { BEGIN ISOLATION LEVEL READ COMMITTED; } step "merge1" { MERGE INTO target t USING (SELECT 1 as key, 'merge1' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge1'; } step "delete1" { DELETE FROM target WHERE key = 1; } step "insert1" { INSERT INTO target VALUES (1, 'insert1'); } step "c1" { COMMIT; } step "a1" { ABORT; } session "s2" setup { BEGIN ISOLATION LEVEL READ COMMITTED; } step "merge2" { MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN NOT MATCHED THEN INSERT VALUES (s.key, s.val) WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2'; } step "merge2i" { MERGE INTO target t USING (SELECT 1 as key, 'merge2' as val) s ON s.key = t.key WHEN MATCHED THEN UPDATE set val = t.val || ' updated by merge2'; } step "select2" { SELECT * FROM target; } step "c2" { COMMIT; } step "a2" { ABORT; } # Basic effects permutation "merge1" "c1" "select2" "c2" permutation "merge1" "c1" "merge2" "select2" "c2" # check concurrent inserts permutation "insert1" "merge2" "c1" "select2" "c2" permutation "merge1" "merge2" "c1" "select2" "c2" permutation "merge1" "merge2" "a1" "select2" "c2" # check how we handle when visible row has been concurrently deleted, then same key re-inserted permutation "delete1" "insert1" "c1" "merge2" "select2" "c2" permutation "delete1" "insert1" "merge2" "c1" "select2" "c2" permutation "delete1" "insert1" "merge2i" "c1" "select2" "c2"