Commit e77888f5 authored by unknown's avatar unknown
Browse files

Fixed bug #18237. 

The code in opt_sum_query that prevented the COUNT/MIN/MAX 
optimization from being applied to outer joins  was not adjusted 
after introducing nested joins. As a result if an outer join
contained a reference to a view as an inner table the code of
opt_sum_query missed the presence of an on expressions and
erroneously applied the mentioned optimization.


mysql-test/r/view.result:
  Added a test case for bug #18237.
mysql-test/t/view.test:
  Added a test case for bug #18237.
parent 8eb2b474

mysql-test/r/view.result

+17 −0
Original line number Diff line number Diff line
@@ -2562,3 +2562,20 @@ my_sqrt 
1.4142135623731

DROP VIEW v1;

DROP TABLE t1;

CREATE TABLE t1 (id int PRIMARY KEY);

CREATE TABLE t2 (id int PRIMARY KEY);

INSERT INTO t1 VALUES (1), (3);

INSERT INTO t2 VALUES (1), (2), (3);

CREATE VIEW v2 AS SELECT * FROM t2;

SELECT COUNT(*) FROM t1 LEFT JOIN t2 ON t1.id=t2.id;

COUNT(*)

2

SELECT * FROM t1 LEFT JOIN t2 ON t1.id=t2.id;

id	id

1	1

3	3

SELECT COUNT(*) FROM t1 LEFT JOIN v2 ON t1.id=v2.id;

COUNT(*)

2

DROP VIEW v2;

DROP TABLE t1, t2;

mysql-test/t/view.test

+21 −0
Original line number Diff line number Diff line
@@ -2413,3 +2413,24 @@ SELECT my_sqrt FROM v1 ORDER BY my_sqrt; 


DROP VIEW v1;

DROP TABLE t1;



#

# Bug #18237: invalid count optimization applied to an outer join with a view 

#             



CREATE TABLE t1 (id int PRIMARY KEY);

CREATE TABLE t2 (id int PRIMARY KEY);



INSERT INTO t1 VALUES (1), (3);

INSERT INTO t2 VALUES (1), (2), (3);



CREATE VIEW v2 AS SELECT * FROM t2;



SELECT COUNT(*) FROM t1 LEFT JOIN t2 ON t1.id=t2.id;

SELECT * FROM t1 LEFT JOIN t2 ON t1.id=t2.id;



SELECT COUNT(*) FROM t1 LEFT JOIN v2 ON t1.id=v2.id;



DROP VIEW v2;



DROP TABLE t1, t2;

sql/opt_sum.cc

+7 −1
Original line number Diff line number Diff line
@@ -96,8 +96,14 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) 
  */

  for (TABLE_LIST *tl= tables; tl; tl= tl->next_leaf)

  {

    TABLE_LIST *embedded;

    for (embedded= tl ; embedded; embedded= embedded->embedding)

    {

      if (embedded->on_expr)

        break;

    }

    if (embedded)

    /* Don't replace expression on a table that is part of an outer join */

    if (tl->on_expr)

    {

      outer_tables|= tl->table->map;