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Bug#43612 crash with explain extended, union, order by

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In UNION if we use last SELECT without braces and this
SELECT have ORDER BY clause, such clause belongs to
global UNION. It is parsed like last SELECT
part and used further as 'unit->global_parameters->order_list' value.
During DESCRIBE EXTENDED we call select_lex->print_order() for
last SELECT where order fields refer to tmp table 
which already freed. It leads to crash.
The fix is clean up global_parameters->order_list
instead of fake_select_lex->order_list.
This commit is contained in:
Sergey Glukhov
2009-05-15 12:03:34 +05:00
parent 1ae3d2ac68
commit f024bde473
3 changed files with 39 additions and 2 deletions
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13
mysql-test/r/union.result
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@@ -1518,4 +1518,17 @@ SHOW FIELDS FROM t2;
Field Type Null Key Default Extra
d double(9,6) YES NULL
DROP TABLE t1, t2;
CREATE TABLE t1(a INT);
EXPLAIN EXTENDED
SELECT a FROM t1
UNION
SELECT a FROM t1
ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 system NULL NULL NULL NULL 0 const row not found
2 UNION t1 system NULL NULL NULL NULL 0 const row not found
NULL UNION RESULT <union1,2> ALL NULL NULL NULL NULL NULL Using filesort
Warnings:
Note 1003 select '0' AS `a` from `test`.`t1` union select '0' AS `a` from `test`.`t1` order by `a`
DROP TABLE t1;
End of 5.0 tests