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The following test case produces different result sets for the first and the second SELECT. SELECT is the same, only the value of record_cond_statistics differs.
The same query on 10.0-base or on MariaDB 5.3 or on MySQL 5.6 produces 2 rows, which I assume to be a correct result.
CREATE TABLE t1 (i1 INT) ENGINE=MyISAM;
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INSERT INTO t1 VALUES (9),(8);
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CREATE TABLE t2 (id2 INT, i2 INT) ENGINE=MyISAM;
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INSERT INTO t2 VALUES (1,5),(2,6);
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CREATE TABLE t3 (pk3 INT PRIMARY KEY, i3 INT) ENGINE=MyISAM;
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INSERT INTO t3 VALUES (1,0),(2,6);
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SELECT * FROM t1 AS outer_t1, t2, t3
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WHERE pk3 = id2 AND i2 < SOME ( SELECT i1 FROM t1 WHERE i1 < outer_t1.i1 );
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SET optimizer_switch='record_cond_statistics=on';
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SELECT * FROM t1 AS outer_t1, t2, t3
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WHERE pk3 = id2 AND i2 < SOME ( SELECT i1 FROM t1 WHERE i1 < outer_t1.i1 );
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Results:
SELECT * FROM t1 AS outer_t1, t2, t3
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WHERE pk3 = id2 AND i2 < SOME ( SELECT i1 FROM t1 WHERE i1 < outer_t1.i1 );
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i1 id2 i2 pk3 i3
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9 1 5 1 0
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9 2 6 2 6
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SET optimizer_switch='record_cond_statistics=on';
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SELECT * FROM t1 AS outer_t1, t2, t3
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WHERE pk3 = id2 AND i2 < SOME ( SELECT i1 FROM t1 WHERE i1 < outer_t1.i1 );
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i1 id2 i2 pk3 i3
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9 1 5 1 0
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8 1 5 1 0
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9 2 6 2 6
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8 2 6 2 6
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EXPLAIN with record_cond_statistics=off:
id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY outer_t1 ALL NULL NULL NULL NULL 2 100.00
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1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Subqueries: 2; Using join buffer (flat, BNL join)
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1 PRIMARY t3 eq_ref PRIMARY PRIMARY 4 test.t2.id2 1 100.00
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2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 2 100.00 Using where
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Warnings:
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Note 1276 Field or reference 'test.outer_t1.i1' of SELECT #2 was resolved in SELECT #1
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Note 1003 select `test`.`outer_t1`.`i1` AS `i1`,`test`.`t2`.`id2` AS `id2`,`test`.`t2`.`i2` AS `i2`,`test`.`t3`.`pk3` AS `pk3`,`test`.`t3`.`i3` AS `i3` from `test`.`t1` `outer_t1` join `test`.`t2` join `test`.`t3` where ((`test`.`t3`.`pk3` = `test`.`t2`.`id2`) and <nop>(<expr_cache><`test`.`t2`.`i2`,`test`.`outer_t1`.`i1`>(<in_optimizer>(`test`.`t2`.`i2`,<exists>(select `test`.`t1`.`i1` from `test`.`t1` where ((`test`.`t1`.`i1` < `test`.`outer_t1`.`i1`) and trigcond(((<cache>(`test`.`t2`.`i2`) < `test`.`t1`.`i1`) or isnull(`test`.`t1`.`i1`)))) having trigcond(<is_not_null_test>(`test`.`t1`.`i1`)))))))
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EXPLAIN with record_cond_statistics=on:
id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY outer_t1 ALL NULL NULL NULL NULL 2 100.00
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1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Subqueries: 2; Using join buffer (flat, BNL join)
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1 PRIMARY t3 eq_ref PRIMARY PRIMARY 4 test.t2.id2 1 100.00 Using where
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2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 2 100.00 Using where
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Warnings:
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Note 1276 Field or reference 'test.outer_t1.i1' of SELECT #2 was resolved in SELECT #1
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Note 1003 select `test`.`outer_t1`.`i1` AS `i1`,`test`.`t2`.`id2` AS `id2`,`test`.`t2`.`i2` AS `i2`,`test`.`t3`.`pk3` AS `pk3`,`test`.`t3`.`i3` AS `i3` from `test`.`t1` `outer_t1` join `test`.`t2` join `test`.`t3` where ((`test`.`t3`.`pk3` = `test`.`t2`.`id2`) and <nop>(<expr_cache><`test`.`t2`.`i2`,`test`.`outer_t1`.`i1`>(<in_optimizer>(`test`.`t2`.`i2`,<exists>(select `test`.`t1`.`i1` from `test`.`t1` where ((`test`.`t1`.`i1` < `test`.`outer_t1`.`i1`) and trigcond(((<cache>(`test`.`t2`.`i2`) < `test`.`t1`.`i1`) or isnull(`test`.`t1`.`i1`)))) having trigcond(<is_not_null_test>(`test`.`t1`.`i1`)))))))
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