CREATE TABLE IF NOT EXISTS t0(c0 FLOAT);
CREATE TABLE IF NOT EXISTS t1 LIKE t0;
SET SESSION internal_tmp_mem_storage_engine = MEMORY;
DROP INDEX c0 ON t1;
INSERT INTO t1(c0) VALUES(NULL);
INSERT INTO t1(c0) VALUES(NULL);
INSERT INTO t1(c0) VALUES(1);
INSERT INTO t1(c0) VALUES(2);
UPDATE t1 SET c0=(IF(t1.c0, NULL, t1.c0)) IS FALSE;
UPDATE t1 SET c0=COALESCE((- (t1.c0)), (3) IS TRUE);
INSERT INTO t0(c0) VALUES(NULL);
INSERT INTO t0(c0) VALUES(NULL);
INSERT INTO t0(c0) VALUES("0");
INSERT INTO t0(c0) VALUES(4);
INSERT INTO t0(c0) VALUES(5);
INSERT INTO t0(c0) VALUES(6);

SELECT t0.c0 FROM t0 WHERE NOT EXISTS (SELECT 1 FROM t1 WHERE t0.c0 = t1.c0);
–

{ NULL, NULL, 0, 4, 5, 6 }
SELECT t0.c0 FROM t0 WHERE EXISTS (SELECT 1 FROM t1 WHERE t0.c0 = t1.c0);
--{ 0 }
SELECT t0.c0 FROM t0;
–{ NULL, NULL, 0, 4, 5, 6 }

When using the same join conditions, the output of semi-join and anti-join are contradictory. This indicates that semi join produce wrong results.