SET optimizer_switch='exists_to_in=on';

CREATE TABLE t1 (a INT) ENGINE=MyISAM;

INSERT INTO t1 VALUES (1),(2);

CREATE ALGORITHM=MERGE VIEW v1 AS SELECT * FROM t1;

CREATE TABLE t2 (b INT) ENGINE=MyISAM;

INSERT INTO t2 VALUES (2),(3);

SELECT * FROM v1 WHERE EXISTS ( SELECT * FROM t2 t2x, t2 t2y WHERE t2y.b = a );

PREPARE stmt FROM "SELECT * FROM v1 WHERE EXISTS ( SELECT * FROM t2 t2x, t2 t2y WHERE t2y.b = a )";

EXECUTE stmt;

EXECUTE stmt;

MariaDB [test]> SELECT * FROM v1 WHERE EXISTS ( SELECT * FROM t2 t2x, t2 t2y WHERE t2y.b = a );

+------+

| a    |

+------+

|    2 |

+------+

1 row in set (0.01 sec)

MariaDB [test]> PREPARE stmt FROM "SELECT * FROM v1 WHERE EXISTS ( SELECT * FROM t2 t2x, t2 t2y WHERE t2y.b = a );";

Query OK, 0 rows affected (0.00 sec)

Statement prepared

MariaDB [test]> EXECUTE stmt;

+------+

| a    |

+------+

|    2 |

+------+

1 row in set (0.00 sec)

MariaDB [test]> EXECUTE stmt;

Empty set (0.00 sec)