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# The server must support partitioning.
--source include/have_partition.inc
--disable_warnings
drop table if exists t1,t2;
--enable_warnings
--echo #
--echo # Bug#50939: Loose Index Scan unduly relies on engine to remember range
--echo # endpoints
--echo #
CREATE TABLE t1 (
a INT,
b INT,
KEY ( a, b )
) PARTITION BY HASH (a) PARTITIONS 1;
CREATE TABLE t2 (
a INT,
b INT,
KEY ( a, b )
);
INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
INSERT INTO t1 SELECT a + 5, b + 5 FROM t1;
INSERT INTO t1 SELECT a + 10, b + 10 FROM t1;
INSERT INTO t1 SELECT a + 20, b + 20 FROM t1;
INSERT INTO t1 SELECT a + 40, b + 40 FROM t1;
INSERT INTO t2 SELECT * FROM t1;
--echo # plans should be identical
EXPLAIN SELECT a, MAX(b) FROM t1 WHERE a IN (10,100) GROUP BY a;
EXPLAIN SELECT a, MAX(b) FROM t2 WHERE a IN (10,100) GROUP BY a;
--disable_ps2_protocol
FLUSH status;
SELECT a, MAX(b) FROM t1 WHERE a IN (10, 100) GROUP BY a;
--echo # Should be no more than 4 reads.
SHOW status LIKE 'handler_read_key';
FLUSH status;
SELECT a, MAX(b) FROM t2 WHERE a IN (10, 100) GROUP BY a;
--echo # Should be no more than 4 reads.
SHOW status LIKE 'handler_read_key';
--enable_ps2_protocol
DROP TABLE t1, t2;
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