Commit 1731161f authored by monty@tik.mysql.fi's avatar monty@tik.mysql.fi
Browse files

Fixed optimizer bug in ORDER BY where some ORDER BY parts where ignored. 

Extended default arguments to be up to 4095 characters
parent 1ebd29ac

Docs/manual.texi

+51 −1030

File changed.

Preview size limit exceeded, changes collapsed.

mysql-test/r/order_by.result

+31 −0
Original line number Diff line number Diff line
@@ -111,3 +111,34 @@ DateOfAction TransactionID 
member_id	nickname	voornaam

1		

2		

gid	sid	uid

104620	5	15

103867	5	27

103962	5	27

104619	5	75

104505	5	117

103853	5	250

gid	sid	uid

104620	5	15

103867	5	27

103962	5	27

104619	5	75

104505	5	117

103853	5	250

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	index	PRIMARY	PRIMARY	4	NULL	6	Using index

t2	eq_ref	PRIMARY,uid	PRIMARY	4	t1.gid	1	

t3	eq_ref	PRIMARY	PRIMARY	2	t2.uid	1	where used; Using index

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	index	PRIMARY	PRIMARY	4	NULL	6	Using index

t3	eq_ref	PRIMARY	PRIMARY	2	t1.gid	1	where used

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	index	PRIMARY	PRIMARY	4	NULL	6	Using index; Using temporary; Using filesort

t2	eq_ref	PRIMARY,uid	PRIMARY	4	t1.gid	1	

t3	eq_ref	PRIMARY	PRIMARY	2	t2.uid	1	where used; Using index

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	index	PRIMARY	PRIMARY	4	NULL	6	Using index; Using temporary; Using filesort

t3	eq_ref	PRIMARY	PRIMARY	2	t1.gid	1	where used

table	type	possible_keys	key	key_len	ref	rows	Extra

t1	ALL	NULL	NULL	NULL	NULL	6	Using temporary; Using filesort

t3	eq_ref	PRIMARY	PRIMARY	2	t1.skr	1	where used

mysql-test/t/order_by.test

+47 −5
Original line number Diff line number Diff line
@@ -168,8 +168,8 @@ drop table t1,t2,t3; 


#bug reported by Wouter de Jong



drop table if exists members;

CREATE TABLE members (

drop table if exists t1;

CREATE TABLE t1 (

  member_id int(11) NOT NULL auto_increment,

  inschrijf_datum varchar(20) NOT NULL default '',

  lastchange_datum varchar(20) NOT NULL default '',
@@ -200,8 +200,50 @@ CREATE TABLE members ( 
  PRIMARY KEY  (member_id)

) TYPE=MyISAM PACK_KEYS=1;



insert into members (member_id) values (1),(2),(3);

select member_id, nickname, voornaam FROM members

insert into t1 (member_id) values (1),(2),(3);

select member_id, nickname, voornaam FROM t1

ORDER by lastchange_datum DESC LIMIT 2;

drop table members;

drop table t1;



#

# Test optimizing bug with EQ_REF tables, where some ORDER BY parts where

# wrongly removed.



CREATE TABLE t1 (

  gid int(10) unsigned NOT NULL auto_increment,

  cid smallint(5) unsigned NOT NULL default '0',

  PRIMARY KEY  (gid),

  KEY component_id (cid)

) TYPE=MyISAM;

INSERT INTO t1 VALUES (103853,108),(103867,108),(103962,108),(104505,108),(104619,108),(104620,108);

ALTER TABLE t1 add skr int(10) not null;



CREATE TABLE t2 (

  gid int(10) unsigned NOT NULL default '0',

  uid smallint(5) unsigned NOT NULL default '1',

  sid tinyint(3) unsigned NOT NULL default '1',

  PRIMARY KEY  (gid),

  KEY uid (uid),

  KEY status_id (sid)

) TYPE=MyISAM;

INSERT INTO t2 VALUES (103853,250,5),(103867,27,5),(103962,27,5),(104505,117,5),(104619,75,5),(104620,15,5);



CREATE TABLE t3 (

  uid smallint(6) NOT NULL auto_increment,

  PRIMARY KEY  (uid)

) TYPE=MyISAM;

INSERT INTO t3 VALUES (1),(15),(27),(75),(117),(250);

ALTER TABLE t3 add skr int(10) not null;



select t1.gid, t2.sid, t3.uid from t2, t1, t3 where t2.gid = t1.gid and t2.uid = t3.uid order by t3.uid, t1.gid;

select t1.gid, t2.sid, t3.uid from t3, t2, t1 where t2.gid = t1.gid and t2.uid = t3.uid order by t3.uid, t1.gid;



# The following ORDER BY can be optimimized

EXPLAIN select t1.gid, t2.sid, t3.uid from t3, t2, t1 where t2.gid = t1.gid and t2.uid = t3.uid order by t1.gid, t3.uid;

EXPLAIN SELECT t1.gid, t3.uid from t1, t3 where t1.gid = t3.uid order by t1.gid,t3.skr;



# The following ORDER BY can't be optimimized

EXPLAIN SELECT t1.gid, t2.sid, t3.uid from t2, t1, t3 where t2.gid = t1.gid and t2.uid = t3.uid order by t3.uid, t1.gid;

EXPLAIN SELECT t1.gid, t3.uid from t1, t3 where t1.gid = t3.uid order by t3.skr,t1.gid;

EXPLAIN SELECT t1.gid, t3.uid from t1, t3 where t1.skr = t3.uid order by t1.gid,t3.skr;

drop table t1,t2,t3;

mysys/default.c

+1 −1
Original line number Diff line number Diff line
@@ -222,7 +222,7 @@ static my_bool search_default_file(DYNAMIC_ARRAY *args, MEM_ROOT *alloc, 
				   const char *dir, const char *config_file,

				   const char *ext, TYPELIB *group)

{

  char name[FN_REFLEN+10],buff[FN_REFLEN+1],*ptr,*end,*value,*tmp;

  char name[FN_REFLEN+10],buff[4096],*ptr,*end,*value,*tmp;

  FILE *fp;

  uint line=0;

  my_bool read_values=0,found_group=0;

sql/sql_select.cc

+6 −6
Original line number Diff line number Diff line
@@ -2649,12 +2649,12 @@ static void update_depend_map(JOIN *join) 
    for (i=0 ; i < ref->key_parts ; i++,item++)

      depend_map|=(*item)->used_tables();

    ref->depend_map=depend_map;

    for (JOIN_TAB *join_tab2=join->join_tab;

    for (JOIN_TAB **tab=join->map2table;

	 depend_map ;

	 join_tab2++,depend_map>>=1 )

	 tab++,depend_map>>=1 )

    {

      if (depend_map & 1)

	ref->depend_map|=join_tab2->ref.depend_map;

	ref->depend_map|=(*tab)->ref.depend_map;

    }

  }

}
@@ -2671,12 +2671,12 @@ static void update_depend_map(JOIN *join, ORDER *order) 
    order->depend_map=depend_map=order->item[0]->used_tables();

    if (!(order->depend_map & RAND_TABLE_BIT))	// Not item_sum() or RAND()

    {

      for (JOIN_TAB *join_tab=join->join_tab;

      for (JOIN_TAB **tab=join->map2table;

	   depend_map ;

	   join_tab++, depend_map>>=1)

	   tab++, depend_map>>=1)

      {

	if (depend_map & 1)

	  order->depend_map|=join_tab->ref.depend_map;

	  order->depend_map|=(*tab)->ref.depend_map;

      }

    }

  }