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now all tables of query are locked in one place (including derived tables)

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fixed BUG#2120 and other problem with EXPLAINing derived tables
This commit is contained in:
bell@sanja.is.com.ua
2004-02-01 15:30:32 +02:00
parent 95fcfaf63c
commit 2a9cd37cd6
18 changed files with 311 additions and 248 deletions
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23
mysql-test/r/derived.result
View File

@ -59,7 +59,7 @@ explain select * from t1 as x1, (select * from t1) as x2;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY x1 ALL NULL NULL NULL NULL 4
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 4
2 DERIVED x1 ALL NULL NULL NULL NULL 4
2 DERIVED t1 ALL NULL NULL NULL NULL 4
drop table if exists t2,t3;
select * from (select 1) as a;
1
@ -141,7 +141,7 @@ a t
explain select count(*) from t1 as tt1, (select * from t1) as tt2;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
2 DERIVED tt1 ALL NULL NULL NULL NULL 10000
2 DERIVED t1 index NULL a 4 NULL 10000 Using index
drop table t1;
SELECT * FROM (SELECT (SELECT * FROM (SELECT 1 as a) as a )) as b;
(SELECT * FROM (SELECT 1 as a) as a )
@ -189,13 +189,13 @@ id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY m2 ALL NULL NULL NULL NULL 9
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 6 Using where
2 DERIVED mp ALL NULL NULL NULL NULL 9 Using temporary; Using filesort
2 DERIVED m2 index NULL PRIMARY 3 NULL 9 Using index
2 DERIVED m1 index NULL PRIMARY 3 NULL 9 Using index
explain SELECT STRAIGHT_JOIN d.pla_id, m2.test FROM t1 m2 INNER JOIN (SELECT mp.pla_id, MIN(m1.matintnum) AS matintnum FROM t2 mp INNER JOIN t1 m1 ON mp.mat_id=m1.mat_id GROUP BY mp.pla_id) d ON d.matintnum=m2.matintnum;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY m2 ALL NULL NULL NULL NULL 9
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 6 Using where
2 DERIVED mp ALL NULL NULL NULL NULL 9 Using temporary; Using filesort
2 DERIVED m2 index NULL PRIMARY 3 NULL 9 Using index
2 DERIVED m1 index NULL PRIMARY 3 NULL 9 Using index
drop table t1,t2;
SELECT a.x FROM (SELECT 1 AS x) AS a HAVING a.x = 1;
x
@ -229,8 +229,8 @@ explain select count(*) from t1 INNER JOIN (SELECT A.E1, A.E2, A.E3 FROM t1 AS A
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 2
1 PRIMARY t1 eq_ref PRIMARY PRIMARY 4 THEMAX.E2 1 Using where
2 DERIVED t1 ALL NULL NULL NULL NULL 2 Using where
3 DEPENDENT SUBQUERY B ALL NULL NULL NULL NULL 2 Using where
2 DERIVED A index NULL PRIMARY 4 NULL 2 Using where; Using index
3 DEPENDENT SUBQUERY B index NULL PRIMARY 4 NULL 2 Using where; Using index
drop table t1;
create table t1 (a int);
insert into t1 values (1),(2);
@ -298,3 +298,14 @@ INSERT INTO t3 VALUES (1000,0.00),(1001,0.25),(1002,0.50),(1003,0.75),(1008,1.00
select 497, TMP.ID, NULL from (select 497 as ID, MAX(t3.DATA) as DATA from t1 join t2 on (t1.ObjectID = t2.ID) join t3 on (t1.ObjectID = t3.ID) group by t2.ParID order by DATA DESC) as TMP;
497 ID NULL
drop table t1, t2, t3;
CREATE TABLE t1 (name char(1) default NULL, val int(5) default NULL);
INSERT INTO t1 VALUES ('a',1), ('a',2), ('a',2), ('a',2), ('a',3), ('a',6), ('a',7), ('a',11), ('a',11), ('a',12), ('a',13), ('a',13), ('a',20), ('b',2), ('b',3), ('b',4), ('b',5);
SELECT s.name, AVG(s.val) AS median FROM (SELECT x.name, x.val FROM t1 x, t1 y WHERE x.name=y.name GROUP BY x.name, x.val HAVING SUM(y.val <= x.val) >= COUNT(*)/2 AND SUM(y.val >= x.val) >= COUNT(*)/2) AS s GROUP BY s.name;
name median
a 7.0000
b 3.5000
explain SELECT s.name, AVG(s.val) AS median FROM (SELECT x.name, x.val FROM t1 x, t1 y WHERE x.name=y.name GROUP BY x.name, x.val HAVING SUM(y.val <= x.val) >= COUNT(*)/2 AND SUM(y.val >= x.val) >= COUNT(*)/2) AS s GROUP BY s.name;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 3 Using temporary; Using filesort
2 DERIVED x ALL NULL NULL NULL NULL 17 Using temporary; Using filesort
2 DERIVED y ALL NULL NULL NULL NULL 17 Using where

9
mysql-test/t/derived.test
View File

@ -183,3 +183,12 @@ CREATE TABLE t3 (
INSERT INTO t3 VALUES (1000,0.00),(1001,0.25),(1002,0.50),(1003,0.75),(1008,1.00),(1009,1.25),(1010,1.50),(1011,1.75);
select 497, TMP.ID, NULL from (select 497 as ID, MAX(t3.DATA) as DATA from t1 join t2 on (t1.ObjectID = t2.ID) join t3 on (t1.ObjectID = t3.ID) group by t2.ParID order by DATA DESC) as TMP;
drop table t1, t2, t3;
#
# explain derived
#
CREATE TABLE t1 (name char(1) default NULL, val int(5) default NULL);
INSERT INTO t1 VALUES ('a',1), ('a',2), ('a',2), ('a',2), ('a',3), ('a',6), ('a',7), ('a',11), ('a',11), ('a',12), ('a',13), ('a',13), ('a',20), ('b',2), ('b',3), ('b',4), ('b',5);
SELECT s.name, AVG(s.val) AS median FROM (SELECT x.name, x.val FROM t1 x, t1 y WHERE x.name=y.name GROUP BY x.name, x.val HAVING SUM(y.val <= x.val) >= COUNT(*)/2 AND SUM(y.val >= x.val) >= COUNT(*)/2) AS s GROUP BY s.name;
explain SELECT s.name, AVG(s.val) AS median FROM (SELECT x.name, x.val FROM t1 x, t1 y WHERE x.name=y.name GROUP BY x.name, x.val HAVING SUM(y.val <= x.val) >= COUNT(*)/2 AND SUM(y.val >= x.val) >= COUNT(*)/2) AS s GROUP BY s.name;