Partitioning by TO_SECONDS(), TO_DAYS() or UNIX_TIMESTAMP() changes the query result: a row with fractional seconds is not found

--source include/have_partition.inc

CREATE TABLE t1 (d DATETIME(6)) PARTITION BY RANGE (TO_SECONDS(d)) (PARTITION p0 VALUES LESS THAN (TO_SECONDS('2020-01-01 00:00:10')), PARTITION p1 VALUES LESS THAN (TO_SECONDS('2020-01-01 00:00:11')), PARTITION p2 VALUES LESS THAN MAXVALUE);

INSERT INTO t1 VALUES ('2020-01-01 00:00:10.5');

--let $c= query_get_value(SELECT COUNT(*) AS c FROM t1 WHERE d > '2020-01-01 00:00:10.4', c, 1)

if ($c != 1)

{

  --die The row 2020-01-01 00:00:10.5 is not found by d > '2020-01-01 00:00:10.4' on a table partitioned by TO_SECONDS(d)

}

CREATE TABLE t2 (d DATETIME(6)) PARTITION BY RANGE (TO_DAYS(d)) (PARTITION p0 VALUES LESS THAN (TO_DAYS('2020-01-01')), PARTITION p1 VALUES LESS THAN (TO_DAYS('2020-01-02')), PARTITION p2 VALUES LESS THAN MAXVALUE);

INSERT INTO t2 VALUES ('2020-01-01 23:59:59.5');

--let $c= query_get_value(SELECT COUNT(*) AS c FROM t2 WHERE d > '2020-01-01 23:59:59', c, 1)

if ($c != 1)

{

  --die The row 2020-01-01 23:59:59.5 is not found by d > '2020-01-01 23:59:59' on a table partitioned by TO_DAYS(d)

}

CREATE TABLE t3 (ts TIMESTAMP(6)) PARTITION BY RANGE (UNIX_TIMESTAMP(ts)) (PARTITION p0 VALUES LESS THAN (UNIX_TIMESTAMP('2020-01-01 00:00:10')), PARTITION p1 VALUES LESS THAN (UNIX_TIMESTAMP('2020-01-01 00:00:11')), PARTITION p2 VALUES LESS THAN MAXVALUE);

INSERT INTO t3 VALUES ('2020-01-01 00:00:10.5');

--let $c= query_get_value(SELECT COUNT(*) AS c FROM t3 WHERE ts > '2020-01-01 00:00:10.4', c, 1)

if ($c != 1)

{

  --die The row 2020-01-01 00:00:10.5 is not found by ts > '2020-01-01 00:00:10.4' on a table partitioned by UNIX_TIMESTAMP(ts)

}

DROP TABLE t1, t2, t3;

mysqltest: At line 8: The row 2020-01-01 00:00:10.5 is not found by d > '2020-01-01 00:00:10.4' on a table partitioned by TO_SECONDS(d)