UNIQUE USING HASH on a partitioned table accepts a duplicate when the statement is pruned

--source include/have_partition.inc

CREATE TABLE t1 (a INT, b VARCHAR(10), UNIQUE (b) USING HASH) PARTITION BY HASH (a) PARTITIONS 4;

INSERT INTO t1 VALUES (1,'x'),(3,'y');

# The row with b='x' is in p1. The WHERE clause prunes the UPDATE to p3

--error 0,ER_DUP_ENTRY

UPDATE t1 SET b='x' WHERE a=3;

--let $c= query_get_value(SELECT COUNT(*) AS c FROM t1 WHERE b='x', c, 1)

if ($c != 1)

{

  --die The UNIQUE USING HASH column b holds $c rows with the value 'x' after UPDATE ... WHERE a=3

}

CREATE TABLE t2 (a INT, b VARCHAR(10), UNIQUE (b) USING HASH) PARTITION BY HASH (a) PARTITIONS 4;

INSERT INTO t2 VALUES (1,'x');

--error 0,ER_DUP_ENTRY

INSERT INTO t2 PARTITION (p2) VALUES (2,'x');

--let $c= query_get_value(SELECT COUNT(*) AS c FROM t2 WHERE b='x', c, 1)

if ($c != 1)

{

  --die The UNIQUE USING HASH column b holds $c rows with the value 'x' after INSERT ... PARTITION (p2)

}

DROP TABLE t1, t2;

mysqltest: At line 11: The UNIQUE USING HASH column b holds 2 rows with the value 'x' after UPDATE ... WHERE a=3