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https://github.com/MariaDB/server.git
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Added test cases for preceding test
This includes all test changes from
"Changing all cost calculation to be given in milliseconds"
and forwards.
Some of the things that caused changes in the result files:
- As part of fixing tests, I added 'echo' to some comments to be able to
easier find out where things where wrong.
- MATERIALIZED has now a higher cost compared to X than before. Because
of this some MATERIALIZED types have changed to DEPENDEND SUBQUERY.
- Some test cases that required MATERIALIZED to repeat a bug was
changed by adding more rows to force MATERIALIZED to happen.
- 'Filtered' in SHOW EXPLAIN has in many case changed from 100.00 to
something smaller. This is because now filtered also takes into
account the smallest possible ref access and filters, even if they
where not used. Another reason for 'Filtered' being smaller is that
we now also take into account implicit filtering done for subqueries
using FIRSTMATCH.
(main.subselect_no_exists_to_in)
This is caluculated in best_access_path() and stored in records_out.
- Table orders has changed because more accurate costs.
- 'index' and 'ALL' for small tables has changed to use 'range' or
'ref' because of optimizer_scan_setup_cost.
- index can be changed to 'range' as 'range' optimizer assumes we don't
have to read the blocks from disk that range optimizer has already read.
This can be confusing in the case where there is no obvious where clause
but instead there is a hidden 'key_column > NULL' added by the optimizer.
(main.subselect_no_exists_to_in)
- Scan on primary clustered key does not report 'Using Index' anymore
(It's a table scan, not an index scan).
- For derived tables, the number of rows is now 100 instead of 2,
which can be seen in EXPLAIN.
- More tests have "Using index for group by" as the cost of this
optimization is now more correct (lower).
- A primary key could be preferred for a normal key, even if it would
access more rows, as it's faster to do 1 lokoup and 3 'index_next' on a
clustered primary key than one lookup trough a secondary.
(main.stat_tables_innodb)
Notes:
- There was a 4.7% more calls to best_extension_by_limited_search() in
the main.greedy_optimizer test. However examining the test results
it looked that the plans where slightly better (eq_ref where more
chained together) so I assume this is ok.
- I have verified a few test cases where there was notable/unexpected
changes in the plan and in all cases the new optimizer plans where
faster. (main.greedy_optimizer and some others)
This commit is contained in:
Monty
Sergei Petrunia
@ -1433,6 +1433,9 @@ drop table if exists t1;
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(SELECT 1 as a) UNION (SELECT 1) ORDER BY (SELECT a+0);
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a
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1
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#
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# IN subselect optimization test
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#
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create table t1 (a int not null, b int, primary key (a));
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create table t2 (a int not null, primary key (a));
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create table t3 (a int not null, b int, primary key (a));
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@ -1479,42 +1482,48 @@ insert into t1 values (1,10), (2,20), (3,30), (4,40);
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create table t0(a int);
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insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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insert into t1
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select rand()*100000+200,rand()*100000 from t0 A, t0 B, t0 C, t0 D;
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select rand()*100000+200,rand(1)*100000 from t0 A, t0 B, t0 C, t0 D;
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insert into t2 values (2), (3), (4), (5);
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insert into t3 values (10,3), (20,4), (30,5);
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explain extended select * from t2 where t2.a in (select a from t1);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
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1 PRIMARY t1 ref a a 5 test.t2.a 101 0.99 Using index; FirstMatch(t2)
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Warnings:
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where `test`.`t1`.`a` = `test`.`t2`.`a`
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select * from t2 where t2.a in (select a from t1);
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a
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2
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3
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4
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explain extended select * from t2 where t2.a in (select a from t1);
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explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
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1 PRIMARY t1 ref a a 5 test.t2.a 101 100.00 Using index; FirstMatch(t2)
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1 PRIMARY t1 ref a a 5 test.t2.a 101 0.99 Using where; Using index; FirstMatch(t2)
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Warnings:
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where `test`.`t1`.`a` = `test`.`t2`.`a`
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where `test`.`t1`.`a` = `test`.`t2`.`a` and `test`.`t1`.`b` <> 30
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select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
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a
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2
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4
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explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
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explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
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1 PRIMARY t1 ref a a 5 test.t2.a 101 100.00 Using where; Using index; FirstMatch(t2)
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1 PRIMARY t3 range a a 5 NULL 3 100.00 Using where; Using index
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1 PRIMARY t1 ref a a 10 test.t2.a,test.t3.a 116 0.29 Using index; FirstMatch(t2)
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Warnings:
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where `test`.`t1`.`a` = `test`.`t2`.`a` and `test`.`t1`.`b` <> 30
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1` join `test`.`t3`) where `test`.`t1`.`b` = `test`.`t3`.`a` and `test`.`t1`.`a` = `test`.`t2`.`a`
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select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
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a
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2
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3
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explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
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insert into t1 values (3,31);
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explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
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1 PRIMARY t3 index a a 5 NULL 3 100.00 Using where; Using index
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1 PRIMARY t1 ref a a 10 test.t2.a,test.t3.a 116 100.00 Using index; FirstMatch(t2)
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1 PRIMARY t1 ref a a 5 test.t2.a 101 0.99 Using where; Using index; FirstMatch(t2)
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Warnings:
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1` join `test`.`t3`) where `test`.`t1`.`b` = `test`.`t3`.`a` and `test`.`t1`.`a` = `test`.`t2`.`a`
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insert into t1 values (3,31);
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where `test`.`t1`.`a` = `test`.`t2`.`a` and `test`.`t1`.`b` <> 30
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select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
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a
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2
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@ -1524,12 +1533,6 @@ select * from t2 where t2.a in (select a from t1 where t1.b <> 30 and t1.b <> 31
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a
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2
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4
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explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
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1 PRIMARY t1 ref a a 5 test.t2.a 101 100.00 Using where; Using index; FirstMatch(t2)
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Warnings:
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Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where `test`.`t1`.`a` = `test`.`t2`.`a` and `test`.`t1`.`b` <> 30
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drop table t0, t1, t2, t3;
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create table t1 (a int, b int);
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create table t2 (a int, b int);
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@ -1591,6 +1594,9 @@ Note 1003 (select 'tttt' AS `s1` from dual)
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s1
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tttt
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drop table t1;
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#
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# IN optimisation test results
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#
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create table t1 (s1 char(5), index s1(s1));
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create table t2 (s1 char(5), index s1(s1));
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insert into t1 values ('a1'),('a2'),('a3');
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@ -1618,21 +1624,21 @@ a3 1
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explain extended select s1, s1 NOT IN (SELECT s1 FROM t2) from t1;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t1 index NULL s1 6 NULL 3 100.00 Using index
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2 DEPENDENT SUBQUERY t2 index s1 s1 6 NULL 2 100.00 Using where; Using index
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2 SUBQUERY t2 index_subquery s1 s1 6 func 2 100.00 Using index; Full scan on NULL key
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Warnings:
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Note 1003 /* select#1 */ select `test`.`t1`.`s1` AS `s1`,!<expr_cache><`test`.`t1`.`s1`>(<in_optimizer>(`test`.`t1`.`s1`,<exists>(/* select#2 */ select `test`.`t2`.`s1` from `test`.`t2` where trigcond(<cache>(`test`.`t1`.`s1`) = `test`.`t2`.`s1` or `test`.`t2`.`s1` is null) having trigcond(`test`.`t2`.`s1` is null)))) AS `s1 NOT IN (SELECT s1 FROM t2)` from `test`.`t1`
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Note 1003 /* select#1 */ select `test`.`t1`.`s1` AS `s1`,!<expr_cache><`test`.`t1`.`s1`>(<in_optimizer>(`test`.`t1`.`s1`,<exists>(<index_lookup>(<cache>(`test`.`t1`.`s1`) in t2 on s1 checking NULL having trigcond(`test`.`t2`.`s1` is null))))) AS `s1 NOT IN (SELECT s1 FROM t2)` from `test`.`t1`
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explain extended select s1, s1 = ANY (SELECT s1 FROM t2) from t1;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t1 index NULL s1 6 NULL 3 100.00 Using index
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2 DEPENDENT SUBQUERY t2 index s1 s1 6 NULL 2 100.00 Using where; Using index
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2 SUBQUERY t2 index_subquery s1 s1 6 func 2 100.00 Using index; Full scan on NULL key
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Warnings:
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Note 1003 /* select#1 */ select `test`.`t1`.`s1` AS `s1`,<expr_cache><`test`.`t1`.`s1`>(<in_optimizer>(`test`.`t1`.`s1`,<exists>(/* select#2 */ select `test`.`t2`.`s1` from `test`.`t2` where trigcond(<cache>(`test`.`t1`.`s1`) = `test`.`t2`.`s1` or `test`.`t2`.`s1` is null) having trigcond(`test`.`t2`.`s1` is null)))) AS `s1 = ANY (SELECT s1 FROM t2)` from `test`.`t1`
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Note 1003 /* select#1 */ select `test`.`t1`.`s1` AS `s1`,<expr_cache><`test`.`t1`.`s1`>(<in_optimizer>(`test`.`t1`.`s1`,<exists>(<index_lookup>(<cache>(`test`.`t1`.`s1`) in t2 on s1 checking NULL having trigcond(`test`.`t2`.`s1` is null))))) AS `s1 = ANY (SELECT s1 FROM t2)` from `test`.`t1`
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explain extended select s1, s1 <> ALL (SELECT s1 FROM t2) from t1;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t1 index NULL s1 6 NULL 3 100.00 Using index
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2 DEPENDENT SUBQUERY t2 index s1 s1 6 NULL 2 100.00 Using where; Using index
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2 SUBQUERY t2 index_subquery s1 s1 6 func 2 100.00 Using index; Full scan on NULL key
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Warnings:
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Note 1003 /* select#1 */ select `test`.`t1`.`s1` AS `s1`,!<expr_cache><`test`.`t1`.`s1`>(<in_optimizer>(`test`.`t1`.`s1`,<exists>(/* select#2 */ select `test`.`t2`.`s1` from `test`.`t2` where trigcond(<cache>(`test`.`t1`.`s1`) = `test`.`t2`.`s1` or `test`.`t2`.`s1` is null) having trigcond(`test`.`t2`.`s1` is null)))) AS `s1 <> ALL (SELECT s1 FROM t2)` from `test`.`t1`
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Note 1003 /* select#1 */ select `test`.`t1`.`s1` AS `s1`,!<expr_cache><`test`.`t1`.`s1`>(<in_optimizer>(`test`.`t1`.`s1`,<exists>(<index_lookup>(<cache>(`test`.`t1`.`s1`) in t2 on s1 checking NULL having trigcond(`test`.`t2`.`s1` is null))))) AS `s1 <> ALL (SELECT s1 FROM t2)` from `test`.`t1`
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explain extended select s1, s1 NOT IN (SELECT s1 FROM t2 WHERE s1 < 'a2') from t1;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY t1 index NULL s1 6 NULL 3 100.00 Using index
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@ -2424,21 +2430,22 @@ a
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1
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3
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DROP TABLE t1;
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#
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# SELECT(EXISTS * ...)optimisation
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#
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create table t1 (a int, b int);
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insert into t1 values (1,2),(3,4),(5,6),(7,8);
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select * from t1 up where exists (select * from t1 where t1.a=up.a);
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a b
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1 2
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3 4
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5 6
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7 8
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explain extended select * from t1 up where exists (select * from t1 where t1.a=up.a);
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insert into t1 select seq,seq from seq_20_to_40;
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select sum(a+b) from t1 up where exists (select * from t1 where t1.a=up.a);
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sum(a+b)
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1296
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explain extended select sum(a+b) from t1 up where exists (select * from t1 where t1.a=up.a);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY up ALL NULL NULL NULL NULL 4 100.00 Using where
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2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 4 100.00 Using where
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1 PRIMARY up ALL NULL NULL NULL NULL 25 100.00 Using where
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2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 25 100.00 Using where
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Warnings:
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Note 1276 Field or reference 'test.up.a' of SELECT #2 was resolved in SELECT #1
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Note 1003 /* select#1 */ select `test`.`up`.`a` AS `a`,`test`.`up`.`b` AS `b` from `test`.`t1` `up` where <expr_cache><`test`.`up`.`a`>(exists(/* select#2 */ select 1 from `test`.`t1` where `test`.`t1`.`a` = `test`.`up`.`a` limit 1))
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Note 1003 /* select#1 */ select sum(`test`.`up`.`a` + `test`.`up`.`b`) AS `sum(a+b)` from `test`.`t1` `up` where <expr_cache><`test`.`up`.`a`>(exists(/* select#2 */ select 1 from `test`.`t1` where `test`.`t1`.`a` = `test`.`up`.`a` limit 1))
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drop table t1;
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CREATE TABLE t1 (t1_a int);
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INSERT INTO t1 VALUES (1);
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@ -3106,6 +3113,10 @@ retailerID statusID changed
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0048 1 2006-01-06 12:37:50
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0059 1 2006-01-06 12:37:50
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drop table t1;
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#
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# Bug#21180 Subselect with index for both WHERE and ORDER BY
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# produces empty result
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#
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create table t1(a int, primary key (a));
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insert into t1 values (10);
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create table t2 (a int primary key, b varchar(32), c int, unique key cb(c, b));
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@ -3121,7 +3132,7 @@ ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 system PRIMARY NULL NULL NULL 1
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1 PRIMARY r const PRIMARY PRIMARY 4 const 1
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2 SUBQUERY t2 ref cb cb 5 const 1 Using where
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2 SUBQUERY t2 range cb cb 40 NULL 3 Using where
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SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
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ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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ORDER BY t2.c DESC, t2.b DESC LIMIT 1) WHERE t1.a = 10;
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@ -3133,7 +3144,7 @@ ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 system PRIMARY NULL NULL NULL 1
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1 PRIMARY r const PRIMARY PRIMARY 4 const 1
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2 SUBQUERY t2 ref cb cb 5 const 1 Using index condition; Using where
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2 SUBQUERY t2 range cb cb 40 NULL 3 Using index condition
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SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
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ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
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ORDER BY t2.c, t2.b LIMIT 1) WHERE t1.a = 10;
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@ -4233,8 +4244,8 @@ INSERT INTO t2 VALUES (7), (5), (1), (3);
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SELECT id, st FROM t1
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WHERE st IN ('GA','FL') AND EXISTS(SELECT 1 FROM t2 WHERE t2.id=t1.id);
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id st
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3 FL
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1 GA
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3 FL
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7 FL
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SELECT id, st FROM t1
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WHERE st IN ('GA','FL') AND EXISTS(SELECT 1 FROM t2 WHERE t2.id=t1.id)
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@ -4335,6 +4346,9 @@ SELECT ((a1,a2) IN (SELECT * FROM t2 WHERE b2 > 0)) IS NULL FROM t1;
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0
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0
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DROP TABLE t1, t2;
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#
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# Bug#28076 inconsistent binary/varbinary comparison
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#
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CREATE TABLE t1 (s1 BINARY(5), s2 VARBINARY(5));
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INSERT INTO t1 VALUES (0x41,0x41), (0x42,0x42), (0x43,0x43);
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SELECT s1, s2 FROM t1 WHERE s2 IN (SELECT s1 FROM t1);
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@ -4396,8 +4410,8 @@ CREATE INDEX I1 ON t1 (a);
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CREATE INDEX I2 ON t1 (b);
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EXPLAIN SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1);
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t1 ALL I2 NULL NULL NULL 2 Using where
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1 PRIMARY t1 ref I1 I1 2 test.t1.b 2 Using where; Using index; FirstMatch(t1)
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1 PRIMARY t1 index I1 I1 2 NULL 2 Using where; Using index; LooseScan
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1 PRIMARY t1 ref I2 I2 13 test.t1.a 2 Using index condition
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SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1);
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a b
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CREATE TABLE t2 (a VARCHAR(1), b VARCHAR(10));
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@ -4406,15 +4420,15 @@ CREATE INDEX I1 ON t2 (a);
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CREATE INDEX I2 ON t2 (b);
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EXPLAIN SELECT a,b FROM t2 WHERE b IN (SELECT a FROM t2);
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t2 ALL I2 NULL NULL NULL 2 Using where
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1 PRIMARY t2 ref I1 I1 4 test.t2.b 2 Using where; Using index; FirstMatch(t2)
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1 PRIMARY t2 index I1 I1 4 NULL 2 Using where; Using index; LooseScan
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1 PRIMARY t2 ref I2 I2 13 test.t2.a 2 Using index condition
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SELECT a,b FROM t2 WHERE b IN (SELECT a FROM t2);
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a b
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EXPLAIN
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SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1 WHERE LENGTH(a)<500);
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||||
id select_type table type possible_keys key key_len ref rows Extra
|
||||
1 PRIMARY t1 ALL I2 NULL NULL NULL 2 Using where
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||||
1 PRIMARY t1 ref I1 I1 2 test.t1.b 2 Using where; Using index; FirstMatch(t1)
|
||||
1 PRIMARY t1 index I1 I1 2 NULL 2 Using where; Using index; LooseScan
|
||||
1 PRIMARY t1 ref I2 I2 13 test.t1.a 2 Using index condition
|
||||
SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1 WHERE LENGTH(a)<500);
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a b
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DROP TABLE t1,t2;
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@ -5709,6 +5723,7 @@ CREATE TABLE t1 (a int) ;
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INSERT INTO t1 VALUES (NULL), (1), (NULL), (2);
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CREATE TABLE t2 (a int, INDEX idx(a)) ;
|
||||
INSERT INTO t2 VALUES (NULL), (1), (NULL),(1000);
|
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insert into t2 select seq from seq_3_to_500;
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SELECT * FROM t1
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WHERE EXISTS (SELECT a FROM t2 USE INDEX () WHERE t2.a = t1.a);
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a
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@ -5718,7 +5733,7 @@ SELECT * FROM t1
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WHERE EXISTS (SELECT a FROM t2 USE INDEX() WHERE t2.a = t1.a);
|
||||
id select_type table type possible_keys key key_len ref rows Extra
|
||||
1 PRIMARY t1 ALL NULL NULL NULL NULL 4 Using where
|
||||
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 4 Using where
|
||||
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 502 Using where
|
||||
SELECT * FROM t1
|
||||
WHERE EXISTS (SELECT a FROM t2 WHERE t2.a = t1.a);
|
||||
a
|
||||
@ -5728,7 +5743,7 @@ SELECT * FROM t1
|
||||
WHERE EXISTS (SELECT a FROM t2 WHERE t2.a = t1.a);
|
||||
id select_type table type possible_keys key key_len ref rows Extra
|
||||
1 PRIMARY t1 ALL NULL NULL NULL NULL 4 Using where
|
||||
2 DEPENDENT SUBQUERY t2 ref idx idx 5 test.t1.a 2 Using index
|
||||
2 DEPENDENT SUBQUERY t2 ref idx idx 5 test.t1.a 58 Using index
|
||||
DROP TABLE t1,t2;
|
||||
#
|
||||
# BUG#752992: Wrong results for a subquery with 'semijoin=on'
|
||||
@ -5745,9 +5760,9 @@ SET @save_join_cache_level=@@join_cache_level;
|
||||
SET join_cache_level=0;
|
||||
EXPLAIN SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
|
||||
id select_type table type possible_keys key key_len ref rows Extra
|
||||
1 PRIMARY t1 ALL PRIMARY NULL NULL NULL 3
|
||||
1 PRIMARY it eq_ref PRIMARY PRIMARY 4 test.t1.pk 1 Using index
|
||||
1 PRIMARY t2 index NULL PRIMARY 4 NULL 3 Using index; FirstMatch(it)
|
||||
1 PRIMARY it index PRIMARY PRIMARY 4 NULL 3 Using index
|
||||
1 PRIMARY t1 eq_ref PRIMARY PRIMARY 4 test.it.pk 1
|
||||
1 PRIMARY t2 index NULL PRIMARY 4 NULL 3 Using index; FirstMatch(t1)
|
||||
SELECT * FROM t1 WHERE pk IN (SELECT it.pk FROM t2 JOIN t2 AS it ON 1);
|
||||
pk i
|
||||
11 0
|
||||
|
||||
Reference in New Issue
Block a user