[MCOL-4700] Wrong result of a UNION for INT and INT UNSIGNED - Jira

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This problem was found by Gagan Goel while working on ~~MCOL-4612~~ and ~~MCOL-4613~~.

DROP TABLE IF EXISTS t1;

CREATE TABLE t1 (a INT, b INT UNSIGNED) ENGINE=ColumnStore;

INSERT INTO t1 VALUES (-1,1);

SELECT * FROM (SELECT a FROM t1 UNION SELECT b FROM t1) tu;

+------------+

| a          |

+------------+

| 4294967295 |

|          1 |

+------------+

Looks wrong. The expected result would be:

DROP TABLE IF EXISTS t1;

CREATE TABLE t1 (a INT, b INT UNSIGNED) ENGINE=InnoDB;

INSERT INTO t1 VALUES (-1,1);

SELECT * FROM (SELECT a FROM t1 UNION SELECT b FROM t1) tu;

{code:sql}

+------+

| a    |

+------+

|   -1 |

|    1 |

+------+

relates to

MCOL-641 Full DECIMAL support in ColumnStore

MCOL-4612 A subquery with a union for DECIMAL and BIGINT returns zeros

MCOL-4613 Garbage result of a union between huge narrow DECIMAL and BIGINT