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  1. MariaDB Server
  2. MDEV-3876

Wrong result (extra rows) with ALL subquery from a MERGE view

        Details

        • Type: Bug
        • Status: Closed
        • Priority: Major
        • Resolution: Duplicate
        • Affects Version/s: 10.0.0, 5.5.28, 5.3.10
        • Fix Version/s: 10.0.1, 5.5.28a, 5.3.11
        • Component/s: None
        • Labels:
          None

          Description

          The test case below returns different results when a query is run with a MERGE view comparing to a TEMPTABLE view or a base table. I believe that the TEMPTABLE/base table result is correct.
          It can be related to MDEV-3873, there are similarities.

          CREATE TABLE t1 (a INT NOT NULL) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1),(2);

CREATE TABLE t2 (b INT NOT NULL) ENGINE=MyISAM;
INSERT INTO t2 VALUES (1),(3);

CREATE OR REPLACE ALGORITHM=MERGE VIEW v AS SELECT * FROM t2;

SELECT a FROM t1 AS alias
WHERE a >= ALL ( 
SELECT b FROM t1 LEFT JOIN v ON (a = b) 
WHERE a = alias.a );

          Actual result: 

          a
----
1
2

          Result with a TEMPTABLE view or a base table:
          Result: 

          a
----
1

          EXPLAIN with the MERGE view:

          id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	alias	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
2	DEPENDENT SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where; Using join buffer (flat, BNL join)
Warnings:
Note	1276	Field or reference 'test.alias.a' of SELECT #2 was resolved in SELECT #1
Note	1003	select `test`.`alias`.`a` AS `a` from `test`.`t1` `alias` where <not>(<expr_cache><`test`.`alias`.`a`>(<in_optimizer>(`test`.`alias`.`a`,<exists>(select `test`.`t2`.`b` from `test`.`t1` left join (`test`.`t2`) on((`test`.`t2`.`b` = `test`.`t1`.`a`)) where ((`test`.`t1`.`a` = `test`.`alias`.`a`) and (<cache>(`test`.`alias`.`a`) < `test`.`t2`.`b`))))))

          branch: maria/5.3
bzr version-info
revision-id: sergii@pisem.net-20121117155015-4ab41ncach4iavao
date: 2012-11-17 16:50:15 +0100
revno: 3603

          Also reproducible on MariaDB 5.5, 10.0.
          Not reproducible on MariaDB 5.2, MySQL 5.5, 5.6.

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                relates to

                Bug - A problem which impairs or prevents the functions of the product. MDEV-3873 Wrong result (extra rows) with NOT IN and a subquery from a MERGE view

                • Major - Major loss of function.
                • Closed

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                  sanja Oleksandr Byelkin added a comment -

                  Duplicate of https://mariadb.atlassian.net/browse/MDEV-3873

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                  sanja Oleksandr Byelkin added a comment - Duplicate of https://mariadb.atlassian.net/browse/MDEV-3873

                    People

                    • Assignee:
                      sanja Oleksandr Byelkin
                      Reporter:
                      elenst Elena Stepanova
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                      • Created:
                        Updated:
                        Resolved: