1berry/MariaDB-server
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

samall optimisation (any independent query will not save data for rexecution)

Browse Source 
saving/restoring join_tab array (to save it of chnging by create_sort_index() before reexecuting)
(BUG#1523)
This commit is contained in:
bell@laptop.sanja.is.com.ua 2003-10-10 21:49:48 +03:00
parent d6d6c5e1bb
commit 99fe76453e
4 changed files with 52 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
mysql-test/r/subselect.result
View File

@ -1439,3 +1439,14 @@ id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 3 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
drop table if exists t2, t3;
CREATE TABLE t1 (number char(11) NOT NULL default '') TYPE=MyISAM CHARSET=latin1;
INSERT INTO t1 VALUES ('69294728265'),('18621828126'),('89356874041'),('95895001874');
CREATE TABLE t2 (code char(5) NOT NULL default '',UNIQUE KEY code (code)) TYPE=MyISAM CHARSET=latin1;
INSERT INTO t2 VALUES ('1'),('1226'),('1245'),('1862'),('18623'),('1874'),('1967'),('6');
select c.number as phone,(select p.code from t2 p where c.number like concat(p.code, '%') order by length(p.code) desc limit 1) as code from t1 c;
phone code
69294728265 6
18621828126 1862
89356874041 NULL
95895001874 NULL
drop table t1, t2;

10
mysql-test/t/subselect.test
View File

@ -965,3 +965,13 @@ insert into t2 values (2,2), (2,1), (3,3), (3,1);
select * from t3 where a > all (select max(b) from t2 group by a);
explain select * from t3 where a > all (select max(b) from t2 group by a);
drop table if exists t2, t3;
#
# filesort in subquery (restoring join_tab)
#
CREATE TABLE t1 (number char(11) NOT NULL default '') TYPE=MyISAM CHARSET=latin1;
INSERT INTO t1 VALUES ('69294728265'),('18621828126'),('89356874041'),('95895001874');
CREATE TABLE t2 (code char(5) NOT NULL default '',UNIQUE KEY code (code)) TYPE=MyISAM CHARSET=latin1;
INSERT INTO t2 VALUES ('1'),('1226'),('1245'),('1862'),('18623'),('1874'),('1967'),('6');
select c.number as phone,(select p.code from t2 p where c.number like concat(p.code, '%') order by length(p.code) desc limit 1) as code from t1 c;
drop table t1, t2;

30
sql/sql_select.cc
View File

@ -980,8 +980,7 @@ JOIN::optimize()
}
}
if (select_lex != &thd->lex.select_lex &&
select_lex->linkage != DERIVED_TABLE_TYPE)
if (select_lex->master_unit()->dependent)
{
if (!(tmp_join= (JOIN*)thd->alloc(sizeof(JOIN))))
DBUG_RETURN(-1);
@ -994,10 +993,10 @@ JOIN::optimize()
DBUG_RETURN(0);
}
/*
Restore values in temporary join
*/
void JOIN::restore_tmp()
{
memcpy(tmp_join, this, (size_t) sizeof(JOIN));
@ -1039,12 +1038,29 @@ JOIN::reinit()
if (items0)
set_items_ref_array(items0);
if (join_tab_save)
memcpy(join_tab, join_tab_save, sizeof(JOIN_TAB) * tables);
if (tmp_join)
restore_tmp();
DBUG_RETURN(0);
}
bool
JOIN::save_join_tab()
{
if (!join_tab_save && select_lex->master_unit()->dependent)
{
if (!(join_tab_save= (JOIN_TAB*) thd->alloc(sizeof(JOIN_TAB) * tables)))
return 1;
memcpy(join_tab_save, join_tab, sizeof(JOIN_TAB) * tables);
}
return 0;
}
/*
Exec select
*/
@ -1246,6 +1262,10 @@ JOIN::exec()
if (curr_join->group_list)
{
thd->proc_info= "Creating sort index";
if (curr_join->join_tab == join_tab && save_join_tab())
{
DBUG_VOID_RETURN;
}
if (create_sort_index(thd, curr_join, curr_join->group_list,
HA_POS_ERROR, HA_POS_ERROR) ||
make_group_fields(this, curr_join))
@ -1427,6 +1447,10 @@ JOIN::exec()
}
}
}
if (curr_join->join_tab == join_tab && save_join_tab())
{
DBUG_VOID_RETURN;
}
if (create_sort_index(thd, curr_join,
curr_join->group_list ?
curr_join->group_list : curr_join->order,

6
sql/sql_select.h
View File

@ -131,6 +131,7 @@ class JOIN :public Sql_alloc
{
public:
JOIN_TAB *join_tab,**best_ref,**map2table;
JOIN_TAB *join_tab_save; //saved join_tab for subquery reexecution
TABLE **table,**all_tables,*sort_by_table;
uint tables,const_tables;
uint send_group_parts;
@ -202,7 +203,7 @@ class JOIN :public Sql_alloc
void init(THD *thd_arg, List<Item> &fields, ulong select_options_arg,
select_result *result_arg)
{
join_tab= 0;
join_tab= join_tab_save= 0;
table= 0;
tables= 0;
const_tables= 0;
@ -242,7 +243,7 @@ class JOIN :public Sql_alloc
zero_result_cause= 0;
optimized= 0;
fields_list = fields;
fields_list= fields;
bzero((char*) &keyuse,sizeof(keyuse));
tmp_table_param.copy_field=0;
tmp_table_param.end_write_records= HA_POS_ERROR;
@ -280,6 +281,7 @@ class JOIN :public Sql_alloc
int rollup_send_data(uint idx);
bool test_in_subselect(Item **where);
void clear();
bool save_join_tab();
};