Incorrect behavior for DELETE statements on a GTT table

SET autocommit=0;

SET SQL_MODE='ORACLE';

CREATE GLOBAL TEMPORARY TABLE gtt (c INT) ON COMMIT PRESERVE ROWS;

INSERT INTO gtt(c) VALUES (1);

COMMIT;

SELECT COUNT(*) AS ct FROM gtt;

DELETE FROM gtt WHERE c=1;

SELECT COUNT(*) AS ct FROM gtt;

-- Cleanup

TRUNCATE TABLE gtt;

COMMIT;

DROP TABLE gtt;

SQL>

	CT

----------

	 0

12.2.0-opt>SELECT COUNT(*) AS ct FROM gtt;

+----+

| ct |

+----+

|  1 |

+----+

1 row in set (0.000 sec)

SET autocommit=0;

SET SQL_MODE='ORACLE';

CREATE TEMPORARY TABLE tt (c INT);

INSERT INTO tt(c) VALUES (1);

COMMIT;

SELECT COUNT(*) AS ct FROM tt;

DELETE FROM tt WHERE c=1;

SELECT COUNT(*) AS ct FROM tt;

-- Cleanup

TRUNCATE TABLE tt;

COMMIT;

DROP TABLE tt;

12.2.0-opt>SELECT COUNT(*) AS ct FROM tt;

+----+

| ct |

+----+

|  0 |

+----+

1 row in set (0.000 sec)

SET autocommit=0;

SET SQL_MODE='ORACLE';

CREATE TABLE t (c INT);

INSERT INTO t(c) VALUES (1);

COMMIT;

SELECT COUNT(*) AS ct FROM t;

DELETE FROM t WHERE c=1;

SELECT COUNT(*) AS ct FROM t;

-- Cleanup

TRUNCATE TABLE t;

COMMIT;

DROP TABLE t;

12.2.0-opt>SELECT COUNT(*) AS ct FROM t;

+----+

| ct |

+----+

|  0 |

+----+

1 row in set (0.000 sec)