[MDEV-8680] Wrong result for SELECT..WHERE a IN ('a' COLLATE latin1_bin,'b') AND a='a' - Jira

SET NAMES latin1;

DROP TABLE IF EXISTS t1;

CREATE TABLE t1 (a VARCHAR(10));

INSERT INTO t1 VALUES ('a'),('A');

SELECT * FROM t1 WHERE a IN ('a' COLLATE latin1_bin,'b');

SELECT * FROM t1 WHERE a IN ('a' COLLATE latin1_bin,'b') AND a='a';

The first SELECT correctly returns one row.
The second SELECT erroneously returns two rows. One row is expected.

The problem happens in equal field propagation.

blocks

MDEV-8728 Fix a number of problems in equal field and equal expression propagation

relates to

MDEV-8698 Wrong result for SELECT..WHERE a BETWEEN 'a' AND 'c' COLLATE latin1_bin;