Commit 7a3148a7 authored by unknown's avatar unknown
Browse files

Bug #24778: Innodb: No result when using ORDER BY 

This bug was intruduced by the fix for bug#17212 (in 4.1). It is not 
ok to call test_if_skip_sort_order since this function will 
alter the execution plan. By contract it is not ok to call 
test_if_skip_sort_order in this context.

This bug appears only in the case when the optimizer has chosen 
an index for accessing a particular table but finds a covering 
index that enables it to skip ORDER BY. This happens in 
test_if_skip_sort_order.


mysql-test/r/key.result:
  Bug#24778
  
  test case.
  
  The bug causes the result to be the empty set.
mysql-test/t/key.test:
  Bug#24778
  
  The minimal test case that reveals the bug. The reason for such a 
  complicated schema is that we have to convince the optimizer to 
  pick one index, then discard it in order to be able to skip 
  ORDER BY.
sql/sql_select.cc:
  bug#24778
  
  Removed the call to test_if_skip_sort_order that constituted the
  bug.
parent 4ce3624e

mysql-test/r/key.result

+41 −0
Original line number Diff line number Diff line
@@ -489,3 +489,44 @@ EXPLAIN SELECT MAX(a) FROM t1 FORCE INDEX(a); 
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	1	

drop table t1;

CREATE TABLE t1 (

a INTEGER auto_increment PRIMARY KEY,

b INTEGER NOT NULL,

c INTEGER NOT NULL,

d CHAR(64)

);

CREATE TABLE t2 (

a INTEGER auto_increment PRIMARY KEY,

b INTEGER NOT NULL,

c SMALLINT NOT NULL,

d DATETIME NOT NULL,

e SMALLINT NOT NULL,

f INTEGER NOT NULL,

g INTEGER NOT NULL,  

h SMALLINT NOT NULL,

i INTEGER NOT NULL,

j INTEGER NOT NULL,

UNIQUE INDEX (b),

INDEX (b, d, e, f, g, h, i, j, c),

INDEX (c)

);

INSERT INTO t2 VALUES 

(NULL, 1, 254, '1000-01-01 00:00:00', 257, 0, 0, 0, 0, 0),

(NULL, 2, 1, '2004-11-30 12:00:00', 1, 0, 0, 0, 0, 0),

(NULL, 3, 1, '2004-11-30 12:00:00', 1, 0, 0, 2, -21600, 0),

(NULL, 4, 1, '2004-11-30 12:00:00', 1, 0, 0, 2, -10800, 0),

(NULL, 5, 1, '2004-11-30 12:00:00', 1, 0, 0, 5, -10800, 0),

(NULL, 6, 1, '2004-11-30 12:00:00', 102, 0, 0, 0, 0, 0),

(NULL, 7, 1, '2004-11-30 12:00:00', 105, 2, 0, 0, 0, 0),

(NULL, 8, 1, '2004-11-30 12:00:00', 105, 10, 0, 0, 0, 0);

INSERT INTO t1 (b, c, d) VALUES

(3388000, -553000, NULL),

(3388000, -553000, NULL);

SELECT *

FROM t2 c JOIN t1 pa ON c.b = pa.a 

WHERE c.c = 1

ORDER BY c.b, c.d

;

a	b	c	d	e	f	g	h	i	j	a	b	c	d

2	2	1	2004-11-30 12:00:00	1	0	0	0	0	0	2	3388000	-553000	NULL

DROP TABLE t1, t2;

mysql-test/t/key.test

+48 −0
Original line number Diff line number Diff line
@@ -453,3 +453,51 @@ ALTER TABLE t1 DISABLE KEYS; 
EXPLAIN SELECT MAX(a) FROM t1 FORCE INDEX(a);



drop table t1;



#

# Bug #24778: Innodb: No result when using ORDER BY

#

CREATE TABLE t1 (

  a INTEGER auto_increment PRIMARY KEY,

  b INTEGER NOT NULL,

  c INTEGER NOT NULL,

  d CHAR(64)

);



CREATE TABLE t2 (

  a INTEGER auto_increment PRIMARY KEY,

  b INTEGER NOT NULL,

  c SMALLINT NOT NULL,

  d DATETIME NOT NULL,

  e SMALLINT NOT NULL,

  f INTEGER NOT NULL,

  g INTEGER NOT NULL,  

  h SMALLINT NOT NULL,

  i INTEGER NOT NULL,

  j INTEGER NOT NULL,

  UNIQUE INDEX (b),

  INDEX (b, d, e, f, g, h, i, j, c),

  INDEX (c)

);



INSERT INTO t2 VALUES 

  (NULL, 1, 254, '1000-01-01 00:00:00', 257, 0, 0, 0, 0, 0),

  (NULL, 2, 1, '2004-11-30 12:00:00', 1, 0, 0, 0, 0, 0),

  (NULL, 3, 1, '2004-11-30 12:00:00', 1, 0, 0, 2, -21600, 0),

  (NULL, 4, 1, '2004-11-30 12:00:00', 1, 0, 0, 2, -10800, 0),

  (NULL, 5, 1, '2004-11-30 12:00:00', 1, 0, 0, 5, -10800, 0),

  (NULL, 6, 1, '2004-11-30 12:00:00', 102, 0, 0, 0, 0, 0),

  (NULL, 7, 1, '2004-11-30 12:00:00', 105, 2, 0, 0, 0, 0),

  (NULL, 8, 1, '2004-11-30 12:00:00', 105, 10, 0, 0, 0, 0);



INSERT INTO t1 (b, c, d) VALUES

  (3388000, -553000, NULL),

  (3388000, -553000, NULL);



SELECT *

FROM t2 c JOIN t1 pa ON c.b = pa.a 

WHERE c.c = 1

ORDER BY c.b, c.d

;



DROP TABLE t1, t2;

sql/sql_select.cc

+1 −4
Original line number Diff line number Diff line
@@ -6106,10 +6106,7 @@ make_join_readinfo(JOIN *join, ulonglong options) 
    */

    if (!ordered_set && 

        (table == join->sort_by_table &&

         (!join->order || join->skip_sort_order ||

          test_if_skip_sort_order(tab, join->order, join->select_limit,

                                  1, &table->keys_in_use_for_order_by))

        ) ||

         (!join->order || join->skip_sort_order)) ||

        (join->sort_by_table == (TABLE *) 1 && i != join->const_tables))

      ordered_set= 1;