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Commit 915a8ae4 authored by Igor Babaev's avatar Igor Babaev
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Fixed bug mdev-4349. 

Range analysis of the condition for a non-indexed column may
return an impossible range. This must be taken into account.
parent 70badba5
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Showing with 171 additions and 21 deletions
mysql-test/r/selectivity.result
View file @ 915a8ae4
......@@ -675,4 +675,44 @@ DROP VIEW v1;
DROP TABLE t1,t2;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
set use_stat_tables=@tmp_use_stat_tables;
#
# Bug mdev-4349: impossible range for non-indexed column
#
set optimizer_use_condition_selectivity=3;
create table t1 (a int);
insert into t1 values
(3), (7), (2), (5), (7), (1), (2), (2);
set optimizer_use_condition_selectivity=1;
explain extended
select * from t1 where a < 1 and a > 7;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 8 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where ((`test`.`t1`.`a` < 1) and (`test`.`t1`.`a` > 7))
select * from t1 where a < 1 and a > 7;
a
set optimizer_use_condition_selectivity=3;
explain extended
select * from t1 where a < 1 and a > 7;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where 0
select * from t1 where a < 1 and a > 7;
a
drop table t1;
create table t1 (a int);
insert into t1 values (1);
create table t2 (b int);
insert into t2 values (2),(3);
explain extended
select * from t1 where a in ( select b from t2 ) AND ( a > 3 );
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1003 select 1 AS `a` from (`test`.`t2`) where 0
select * from t1 where a in ( select b from t2 ) AND ( a > 3 );
a
drop table t1,t2;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
set use_stat_tables=@save_use_stat_tables;
mysql-test/r/selectivity_innodb.result
View file @ 915a8ae4
......@@ -681,6 +681,47 @@ DROP VIEW v1;
DROP TABLE t1,t2;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
set use_stat_tables=@tmp_use_stat_tables;
#
# Bug mdev-4349: impossible range for non-indexed column
#
set optimizer_use_condition_selectivity=3;
create table t1 (a int);
insert into t1 values
(3), (7), (2), (5), (7), (1), (2), (2);
set optimizer_use_condition_selectivity=1;
explain extended
select * from t1 where a < 1 and a > 7;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 8 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where ((`test`.`t1`.`a` < 1) and (`test`.`t1`.`a` > 7))
select * from t1 where a < 1 and a > 7;
a
set optimizer_use_condition_selectivity=3;
explain extended
select * from t1 where a < 1 and a > 7;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where 0
select * from t1 where a < 1 and a > 7;
a
drop table t1;
create table t1 (a int);
insert into t1 values (1);
create table t2 (b int);
insert into t2 values (2),(3);
explain extended
select * from t1 where a in ( select b from t2 ) AND ( a > 3 );
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 1 0.00 Using where
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 0 Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`b` = `test`.`t1`.`a`) and (`test`.`t1`.`a` > 3))
select * from t1 where a in ( select b from t2 ) AND ( a > 3 );
a
drop table t1,t2;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
set use_stat_tables=@save_use_stat_tables;
set optimizer_switch=@save_optimizer_switch_for_selectivity_test;
SET SESSION STORAGE_ENGINE=DEFAULT;
mysql-test/t/selectivity.test
View file @ 915a8ae4
......@@ -267,5 +267,40 @@ DROP TABLE t1,t2;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
set use_stat_tables=@tmp_use_stat_tables;
--echo #
--echo # Bug mdev-4349: impossible range for non-indexed column
--echo #
set optimizer_use_condition_selectivity=3;
create table t1 (a int);
insert into t1 values
(3), (7), (2), (5), (7), (1), (2), (2);
set optimizer_use_condition_selectivity=1;
explain extended
select * from t1 where a < 1 and a > 7;
select * from t1 where a < 1 and a > 7;
set optimizer_use_condition_selectivity=3;
explain extended
select * from t1 where a < 1 and a > 7;
select * from t1 where a < 1 and a > 7;
drop table t1;
create table t1 (a int);
insert into t1 values (1);
create table t2 (b int);
insert into t2 values (2),(3);
explain extended
select * from t1 where a in ( select b from t2 ) AND ( a > 3 );
select * from t1 where a in ( select b from t2 ) AND ( a > 3 );
drop table t1,t2;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
set use_stat_tables=@save_use_stat_tables;
sql/opt_range.cc
View file @ 915a8ae4
......@@ -3325,7 +3325,8 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
table->cond_selectivity= 1.0;
if (!bitmap_is_clear_all(used_fields))
if (thd->variables.optimizer_use_condition_selectivity > 2 &&
!bitmap_is_clear_all(used_fields))
{
PARAM param;
MEM_ROOT alloc;
......@@ -3362,9 +3363,25 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
double rows;
if (*key)
{
#if 0
rows= records_in_column_ranges(&param, idx, *key);
if (rows != HA_POS_ERROR)
(*key)->field->cond_selectivity= rows/table_records;
#else
table->reginfo.impossible_range= 0;
if ((*key)->type == SEL_ARG::IMPOSSIBLE)
{
rows= 0;
table->reginfo.impossible_range= 1;
goto free_alloc;
}
else
{
rows= records_in_column_ranges(&param, idx, *key);
if (rows != HA_POS_ERROR)
(*key)->field->cond_selectivity= rows/table_records;
}
#endif
}
}
......
sql/sql_select.cc
View file @ 915a8ae4
......@@ -3794,6 +3794,8 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
all select distinct fields participate in one index.
*/
add_group_and_distinct_keys(join, s);
table->cond_selectivity= 1.0;
/*
Perform range analysis if there are keys it could use (1).
......@@ -3802,7 +3804,8 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
Don't do range analysis for materialized subqueries (4).
Don't do range analysis for materialized derived tables (5)
*/
if (!s->const_keys.is_clear_all() && // (1)
if ((!s->const_keys.is_clear_all() ||
!bitmap_is_clear_all(&s->table->cond_set)) && // (1)
(!s->table->pos_in_table_list->embedding || // (2)
(s->table->pos_in_table_list->embedding && // (3)
s->table->pos_in_table_list->embedding->sj_on_expr)) && // (3)
......@@ -3810,20 +3813,37 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
!(s->table->pos_in_table_list->derived && // (5)
s->table->pos_in_table_list->is_materialized_derived())) // (5)
{
ha_rows records;
SQL_SELECT *select;
select= make_select(s->table, found_const_table_map,
found_const_table_map,
*s->on_expr_ref ? *s->on_expr_ref : conds,
1, &error);
if (!select)
goto error;
records= get_quick_record_count(join->thd, select, s->table,
&s->const_keys, join->row_limit);
s->quick=select->quick;
s->needed_reg=select->needed_reg;
select->quick=0;
if (records == 0 && s->table->reginfo.impossible_range)
bool impossible_range= FALSE;
ha_rows records= HA_POS_ERROR;
SQL_SELECT *select= 0;
if (!s->const_keys.is_clear_all())
{
select= make_select(s->table, found_const_table_map,
found_const_table_map,
*s->on_expr_ref ? *s->on_expr_ref : conds,
1, &error);
if (!select)
goto error;
records= get_quick_record_count(join->thd, select, s->table,
&s->const_keys, join->row_limit);
s->quick=select->quick;
s->needed_reg=select->needed_reg;
select->quick=0;
impossible_range= records == 0 && s->table->reginfo.impossible_range;
}
if (!impossible_range)
{
if (join->thd->variables.optimizer_use_condition_selectivity > 1)
calculate_cond_selectivity_for_table(join->thd, s->table,
*s->on_expr_ref ?
*s->on_expr_ref : conds);
if (s->table->reginfo.impossible_range)
{
impossible_range= TRUE;
records= 0;
}
}
if (impossible_range)
{
/*
Impossible WHERE or ON expression
......@@ -3848,13 +3868,10 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
s->found_records=records;
s->read_time= s->quick ? s->quick->read_time : 0.0;
}
delete select;
if (select)
delete select;
}
if (join->thd->variables.optimizer_use_condition_selectivity > 1)
calculate_cond_selectivity_for_table(join->thd, s->table,
*s->on_expr_ref ?
*s->on_expr_ref : conds);
}
if (pull_out_semijoin_tables(join))
......
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