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MariaDB [test]> select * FROM t1 where d1 in (select d1 from t1 );
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+------+---------------------+
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| id | d1 |
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+------+---------------------+
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| 1 | 2022-11-15 11:00:00 |
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| 1 | 2022-11-15 10:00:00 |
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| 1 | 2022-11-14 11:00:00 |
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+------+---------------------+
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3 rows in set (0,002 sec)
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MariaDB [test]> set optimizer_switch='semijoin=off';
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Query OK, 0 rows affected (0,000 sec)
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MariaDB [test]> select * FROM t1 where d1 in (select d1 from t1 );
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Empty set (0,002 sec)
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MariaDB [test]> analyze select * FROM t1 where d1 in (select t1.d1 from t1 );
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+------+--------------+-------+------+---------------+------+---------+------+------+--------+----------+------------+-------------+
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| id | select_type | table | type | possible_keys | key | key_len | ref | rows | r_rows | filtered | r_filtered | Extra |
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+------+--------------+-------+------+---------------+------+---------+------+------+--------+----------+------------+-------------+
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| 1 | PRIMARY | t1 | ALL | NULL | NULL | NULL | NULL | 3 | 3.00 | 100.00 | 0.00 | Using where |
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| 2 | MATERIALIZED | t1 | ALL | NULL | NULL | NULL | NULL | 3 | NULL | 100.00 | NULL | |
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+------+--------------+-------+------+---------------+------+---------+------+------+--------+----------+------------+-------------+
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2 rows in set (0,002 sec)
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