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-- tests for tidscans
CREATE TABLE tidscan(id integer);
-- only insert a few rows, we don't want to spill onto a second table page
INSERT INTO tidscan VALUES (1), (2), (3);
-- show ctids
-- XXX since rows come from different datanodes, some TIDs can be duplicated in
-- XL
SELECT ctid, * FROM tidscan;
-- ctid equality - implemented as tidscan
EXPLAIN (COSTS OFF)
SELECT ctid, * FROM tidscan WHERE ctid = '(0,1)';
SELECT ctid, * FROM tidscan WHERE ctid = '(0,1)';
EXPLAIN (COSTS OFF)
SELECT ctid, * FROM tidscan WHERE '(0,1)' = ctid;
SELECT ctid, * FROM tidscan WHERE '(0,1)' = ctid;
-- ctid = ScalarArrayOp - implemented as tidscan
EXPLAIN (COSTS OFF)
SELECT ctid, * FROM tidscan WHERE ctid = ANY(ARRAY['(0,1)', '(0,2)']::tid[]);
SELECT ctid, * FROM tidscan WHERE ctid = ANY(ARRAY['(0,1)', '(0,2)']::tid[]);
-- ctid != ScalarArrayOp - can't be implemented as tidscan
EXPLAIN (COSTS OFF)
SELECT ctid, * FROM tidscan WHERE ctid != ANY(ARRAY['(0,1)', '(0,2)']::tid[]);
SELECT ctid, * FROM tidscan WHERE ctid != ANY(ARRAY['(0,1)', '(0,2)']::tid[]);
-- tid equality extracted from sub-AND clauses
EXPLAIN (COSTS OFF)
SELECT ctid, * FROM tidscan
WHERE (id = 3 AND ctid IN ('(0,2)', '(0,3)')) OR (ctid = '(0,1)' AND id = 1);
SELECT ctid, * FROM tidscan
WHERE (id = 3 AND ctid IN ('(0,2)', '(0,3)')) OR (ctid = '(0,1)' AND id = 1);
-- exercise backward scan and rewind
BEGIN;
DECLARE c CURSOR FOR
SELECT ctid, * FROM tidscan WHERE ctid = ANY(ARRAY['(0,1)', '(0,2)']::tid[]);
FETCH ALL FROM c;
-- XL does not support BACKWARD scan of RemoteSubplan/RemoteSubquery and
-- hence the next statement fails
FETCH BACKWARD 1 FROM c;
FETCH FIRST FROM c;
ROLLBACK;
-- tidscan via CURRENT OF
BEGIN;
DECLARE c CURSOR FOR SELECT ctid, * FROM tidscan;
FETCH NEXT FROM c; -- skip one row
FETCH NEXT FROM c;
-- perform update
EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF)
-- XL does not support WHERE CURRENT OF and hence the next
-- statement fails
UPDATE tidscan SET id = -id WHERE CURRENT OF c RETURNING *;
FETCH NEXT FROM c;
-- perform update
EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF)
UPDATE tidscan SET id = -id WHERE CURRENT OF c RETURNING *;
SELECT * FROM tidscan;
-- position cursor past any rows
FETCH NEXT FROM c;
-- should error out
EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF)
UPDATE tidscan SET id = -id WHERE CURRENT OF c RETURNING *;
ROLLBACK;
DROP TABLE tidscan;
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