Details
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Bug
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Status: Stalled (View Workflow)
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Major
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Resolution: Unresolved
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10.3(EOL), 10.4(EOL), 10.5, 10.6, 10.7(EOL), 10.8(EOL), 10.9(EOL), 10.10(EOL), 10.11
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None
Description
The problem was introduced in 5.5 tree with the following revision:
revno: 4030
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revision-id: monty@askmonty.org-20140124125018-qwln430o4bu3pued
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parent: monty@askmonty.org-20140124123019-2ts6q2ip6076gmqg
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committer: Michael Widenius <monty@askmonty.org>
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branch nick: maria-5.5
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timestamp: Fri 2014-01-24 14:50:18 +0200
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message:
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Fix for MDEV-5531: double call procedure in one session - hard shutdown the server
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Main fix was to not cache derivied tables as they may be temporary tables that are deleted before the next query.
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This was a bit tricky as Item_field::fix_fields depended on cached_tables to be set to resolve some columns.
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CREATE TABLE t1 (a INT, b INT) ENGINE=MyISAM; |
CREATE TABLE t2 (c INT) ENGINE=MyISAM; |
INSERT INTO t1 VALUES (1,1),(2,2); |
INSERT INTO t2 VALUES (3),(4); |
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PREPARE stmt FROM 'SELECT * FROM ( SELECT DISTINCT * FROM t1 ) AS sq WHERE a IN ( SELECT c FROM t2 WHERE c <= sq.b )'; |
EXECUTE stmt; |
EXECUTE stmt; |
query 'EXECUTE stmt' failed: 1054: Unknown column 'sq.b' in 'where clause'
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Attachments
Issue Links
- relates to
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- Closed
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simplified prepare (easier to debug):
PREPARE stmt FROM 'SELECT 1 FROM ( SELECT DISTINCT * FROM t1 ) AS sq WHERE a IN ( SELECT 1 FROM t2 WHERE sq.b <= c)';
The problem is that during the first execute, we call, as part of sub query optimization:
void Item_field::fix_after_pullout(st_select_lex *new_parent, Item **ref)
This sets ctx->outer_contex = NULL for the new context.
This causes setup_without_group-> setup_conds for the second execution to not find the outer ref field sq.b.
One can't use the old outer_context for the new context as in fix_outer_field we do:
Item_subselect *prev_subselect_item=
last_checked_context->select_lex->master_unit()->item;
Which is 0 for the new context that was created.