Commit 580b8785 authored by igor@rurik.mysql.com's avatar igor@rurik.mysql.com

The output of explain command for some queries has changed

after introducing Item_equal.
parent 0ba4b082
......@@ -646,3 +646,5 @@ vio/test-ssl
vio/test-sslclient
vio/test-sslserver
vio/viotest-ssl
mysql-test/r/index_merge_load.result
mysql-test/t/index_merge.load
......@@ -140,13 +140,13 @@ id parent_id level
1015 102 2
explain select level from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const 1 Using where; Using index
1 SIMPLE t1 ref level level 1 const 1 Using index
explain select level,id from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const 1 Using where; Using index
1 SIMPLE t1 ref level level 1 const 1 Using index
explain select level,id,parent_id from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const 1 Using where
1 SIMPLE t1 ref level level 1 const 1
select level,id from t1 where level=1;
level id
1 1002
......@@ -625,7 +625,7 @@ id parent_id level
1016 102 2
explain select level from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const 1 Using where; Using index
1 SIMPLE t1 ref level level 1 const 1 Using index
select level,id from t1 where level=1;
level id
1 1004
......
......@@ -412,7 +412,7 @@ CHI Los Angeles
explain
select max(a3) from t1 where a2 is null and a2 = 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
select max(a3) from t1 where a2 is null and a2 = 2;
max(a3)
NULL
......
......@@ -74,9 +74,9 @@ select * from t1 where 1 xor 1;
a
explain extended select * from t1 where 1 xor 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
Warnings:
Note 1003 select high_priority test.t1.a AS `a` from test.t1 where (1 xor 1)
Note 1003 select high_priority test.t1.a AS `a` from test.t1
select - a from t1;
- a
-1
......
......@@ -73,7 +73,7 @@ type=heap;
insert into t1 values (1,1),(2,2),(1,3),(2,4),(2,5),(2,6);
explain select * from t1 where x=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref x x 4 const 1 Using where
1 SIMPLE t1 ref x x 4 const 1
select * from t1 where x=1;
x y
1 1
......@@ -134,7 +134,7 @@ a b
1 1
explain select * from tx where b=x;
id select_type table type possible_keys key key_len ref rows Extra
x SIMPLE tx ref b b x const x Using where
x SIMPLE tx ref b b x const x
drop table t1;
create table t1 (id int unsigned not null, primary key using BTREE (id)) type=HEAP;
insert into t1 values(1);
......
......@@ -76,13 +76,13 @@ id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 ALL i1,i2 NULL NULL NULL 1024 Using where
explain select * from t0 where key2 = 45 or key1 is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 range i1,i2 i2 4 NULL 1 Using where
1 SIMPLE t0 ref i2 i2 4 const 1
explain select * from t0 where key2=10 or key3=3 or key4 <=> null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 index_merge i2,i3,i4 i2,i3 4,4 NULL 2 Using where
explain select * from t0 where key2=10 or key3=3 or key4 is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 index_merge i2,i3,i4 i2,i3 4,4 NULL 2 Using where
1 SIMPLE t0 index_merge i2,i3 i2,i3 4,4 NULL 2 Using where
explain select key1 from t0 where (key1 <=> null) or (key2 < 5) or
(key3=10) or (key4 <=> null);
id select_type table type possible_keys key key_len ref rows Extra
......@@ -257,18 +257,18 @@ explain
select * from t0,t1 where (t0.key1=t1.key1) and
(t0.key1=3 or t0.key2=4) and t1.key1<200;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 2 Using where
1 SIMPLE t1 ref i1 i1 4 test.t0.key1 1 Using where
1 SIMPLE t0 range i1,i2 i1 4 NULL 179 Using where
1 SIMPLE t1 ref i1 i1 4 test.t0.key1 1
explain
select * from t0,t1 where (t0.key1=t1.key1) and
(t0.key1=3 or t0.key2<4) and t1.key1=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 ref i1,i2 i1 4 const 1 Using where
1 SIMPLE t1 ref i1 i1 4 const 1 Using where
1 SIMPLE t1 ref i1 i1 4 const 1
explain select * from t0,t1 where t0.key1 = 5 and
(t1.key1 = t0.key1 or t1.key8 = t0.key1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t0 ref i1 i1 4 const 1 Using where
1 SIMPLE t0 ref i1 i1 4 const 1
1 SIMPLE t1 index_merge i1,i8 i1,i8 4,4 NULL 2 Using where
explain select * from t0,t1 where t0.key1 < 3 and
(t1.key1 = t0.key1 or t1.key8 = t0.key1);
......
......@@ -141,13 +141,13 @@ id parent_id level
1015 102 2
explain select level from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const # Using where; Using index
1 SIMPLE t1 ref level level 1 const # Using index
explain select level,id from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const # Using where; Using index
1 SIMPLE t1 ref level level 1 const # Using index
explain select level,id,parent_id from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const # Using where
1 SIMPLE t1 ref level level 1 const #
select level,id from t1 where level=1;
level id
1 1002
......@@ -609,7 +609,7 @@ id parent_id level
1016 102 2
explain select level from t1 where level=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref level level 1 const # Using where; Using index
1 SIMPLE t1 ref level level 1 const # Using index
select level,id from t1 where level=1;
level id
1 1004
......
......@@ -634,7 +634,7 @@ insert into t2 values (10,1),(20,2),(30,3);
explain select * from t2 left join t1 on t1.fooID = t2.fooID and t1.fooID = 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 index NULL PRIMARY 4 NULL 3 Using index
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 2 const 1 Using where; Using index
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 2 const 1 Using index
select * from t2 left join t1 on t1.fooID = t2.fooID and t1.fooID = 30;
fooID barID fooID
10 1 NULL
......
......@@ -12,5 +12,5 @@ select * from t1 where a is null;
a b
explain select * from t1 where b is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
drop table t1;
......@@ -220,24 +220,22 @@ insert into t1 (x) values (1),(2),(3),(4),(5),(6),(7),(8),(9);
update t1 set y=x;
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between 7 and t1.y+0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 4 Using where
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= 7 and t2.x <= t1.y+0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 4 Using where
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between t1.y-1 and t1.y+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 ALL x NULL NULL NULL 9 Range checked for each record (index map: 0x1)
1 SIMPLE t2 range x x 5 NULL 3 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= t1.y-1 and t2.x <= t1.y+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 ALL x NULL NULL NULL 9 Range checked for each record (index map: 0x1)
1 SIMPLE t2 range x x 5 NULL 3 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between 0 and t1.y;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 ALL x NULL NULL NULL 9 Using where
1 SIMPLE t2 range x x 5 NULL 2 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= 0 and t2.x <= t1.y;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
......@@ -255,12 +253,12 @@ CREATE TABLE t2 (keya int(11) NOT NULL default '0', KEY j1 (keya));
INSERT INTO t2 VALUES (0),(0),(1),(1),(2),(2);
explain select * from t1, t2 where (t1.key1 <t2.keya + 1) and t2.keya=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref j1 j1 4 const 1 Using where; Using index
1 SIMPLE t1 ALL i1,i2 NULL NULL NULL 4 Range checked for each record (index map: 0x3)
1 SIMPLE t2 ref j1 j1 4 const 1 Using index
1 SIMPLE t1 range i1,i2 i1 4 NULL 4 Using where; Using index
explain select * from t1 force index(i2), t2 where (t1.key1 <t2.keya + 1) and t2.keya=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref j1 j1 4 const 1 Using where; Using index
1 SIMPLE t1 ALL i2 NULL NULL NULL 4 Range checked for each record (index map: 0x2)
1 SIMPLE t2 ref j1 j1 4 const 1 Using index
1 SIMPLE t1 range i2 i2 4 NULL 4 Using where; Using index
DROP TABLE t1,t2;
CREATE TABLE t1 (
a int(11) default NULL,
......@@ -379,14 +377,26 @@ count(*)
select count(*) from t2;
count(*)
1026
analyze table t1,t2;
Table Op Msg_type Msg_text
test.t1 analyze status OK
test.t2 analyze status Table is already up to date
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 128 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 128 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid != 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 129 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid != 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 129 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
id name uid id name uid
1001 A 1 1001 A 1
......
......@@ -1374,7 +1374,7 @@ id select_type table type possible_keys key key_len ref rows Extra
explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 and t4.companynr > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 1199 Using where
1 SIMPLE t4 eq_ref PRIMARY PRIMARY 1 test.t2.companynr 1 Using where
1 SIMPLE t4 eq_ref PRIMARY PRIMARY 1 test.t2.companynr 1
explain select t2.companynr,companyname from t4 left join t2 using (companynr) where t2.companynr > 0 or t2.companynr is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t4 ALL NULL NULL NULL NULL 12
......@@ -1470,7 +1470,7 @@ explain extended select count(*),min(fld4),max(fld4),sum(fld1),avg(fld1),std(fld
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 1199 Using where
Warnings:
Note 1003 select high_priority count(0) AS `count(*)`,min(test.t2.fld4) AS `min(fld4)`,max(test.t2.fld4) AS `max(fld4)`,sum(test.t2.fld1) AS `sum(fld1)`,avg(test.t2.fld1) AS `avg(fld1)`,std(test.t2.fld1) AS `std(fld1)`,variance(test.t2.fld1) AS `variance(fld1)` from test.t2 where ((test.t2.companynr = 34) and (test.t2.fld4 <> _latin1''))
Note 1003 select high_priority count(0) AS `count(*)`,min(test.t2.fld4) AS `min(fld4)`,max(test.t2.fld4) AS `max(fld4)`,sum(test.t2.fld1) AS `sum(fld1)`,avg(test.t2.fld1) AS `avg(fld1)`,std(test.t2.fld1) AS `std(fld1)`,variance(test.t2.fld1) AS `variance(fld1)` from test.t2 where ((test.t2.fld4 <> _latin1'') and (test.t2.companynr = 34))
select companynr,count(*),min(fld4),max(fld4),sum(fld1),avg(fld1),std(fld1),variance(fld1) from t2 group by companynr limit 3;
companynr count(*) min(fld4) max(fld4) sum(fld1) avg(fld1) std(fld1) variance(fld1)
00 82 Anthony windmills 10355753 126289.6707 115550.9757 13352027981.7087
......
......@@ -309,7 +309,7 @@ id select_type table type possible_keys key key_len ref rows Extra
Warnings:
Note 1275 Field or reference 't2.a' of SELECT #2 was resolved in SELECT #1
Note 1275 Field or reference 't2.a' of SELECT #3 was resolved in SELECT #1
Note 1003 select high_priority (select test.t1.a AS `a` from test.t1 where (test.t1.a = test.t2.a) union select test.t5.a AS `a` from test.t5 where (test.t5.a = test.t2.a)) AS `(select a from t1 where t1.a=t2.a union select a from t5 where t5.a=t2.a)`,test.t2.a AS `a` from test.t2
Note 1003 select high_priority (select test.t1.a AS `a` from test.t1 where (test.t2.a = test.t1.a) union select test.t5.a AS `a` from test.t5 where (test.t2.a = test.t5.a)) AS `(select a from t1 where t1.a=t2.a union select a from t5 where t5.a=t2.a)`,test.t2.a AS `a` from test.t2
select (select a from t1 where t1.a=t2.a union all select a from t5 where t5.a=t2.a), a from t2;
ERROR 21000: Subquery returns more than 1 row
create table t6 (patient_uq int, clinic_uq int, index i1 (clinic_uq));
......@@ -327,7 +327,7 @@ id select_type table type possible_keys key key_len ref rows Extra
2 DEPENDENT SUBQUERY t7 eq_ref PRIMARY PRIMARY 4 test.t6.clinic_uq 1
Warnings:
Note 1275 Field or reference 'clinic_uq' of SELECT #2 was resolved in SELECT #1
Note 1003 select high_priority test.t6.patient_uq AS `patient_uq`,test.t6.clinic_uq AS `clinic_uq` from test.t6 where exists(select test.t7.uq AS `uq`,test.t7.name AS `name` from test.t7 where (test.t7.uq = test.t6.clinic_uq) limit 1)
Note 1003 select high_priority test.t6.patient_uq AS `patient_uq`,test.t6.clinic_uq AS `clinic_uq` from test.t6 where exists(select test.t7.uq AS `uq`,test.t7.name AS `name` from test.t7 where (test.t6.clinic_uq = test.t7.uq) limit 1)
select * from t1 where a= (select a from t2,t4 where t2.b=t4.b);
ERROR 23000: Column: 'a' in field list is ambiguous
drop table if exists t1,t2,t3;
......@@ -540,7 +540,7 @@ id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
Warnings:
Note 1003 select high_priority test.t1.numreponse AS `numreponse` from test.t1 where ((test.t1.numeropost = _latin1'1') and (test.t1.numreponse = 3))
Note 1003 select high_priority test.t1.numreponse AS `numreponse` from test.t1 where ((test.t1.numeropost = _latin1'1') and (test.t1.numreponse = (select max(test.t1.numreponse) AS `MAX(numreponse)` from test.t1 where (test.t1.numeropost = _latin1'1'))))
drop table t1;
CREATE TABLE t1 (a int(1));
INSERT INTO t1 VALUES (1);
......@@ -899,7 +899,7 @@ id select_type table type possible_keys key key_len ref rows Extra
2 DEPENDENT SUBQUERY t2 ref_or_null a a 5 func 2 Using where; Using index
2 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 3 Using where
Warnings:
Note 1003 select high_priority test.t1.a AS `a`,<in_optimizer>(test.t1.a,<exists>(select 1 AS `Not_used` from test.t2 join test.t3 where ((test.t3.a = test.t2.a) and ((<cache>(test.t1.a) = test.t2.a) or isnull(test.t2.a))) having <is_not_null_test>(test.t2.a) limit 1)) AS `t1.a in (select t2.a from t2,t3 where t3.a=t2.a)` from test.t1
Note 1003 select high_priority test.t1.a AS `a`,<in_optimizer>(test.t1.a,<exists>(select 1 AS `Not_used` from test.t2 join test.t3 where (((<cache>(test.t1.a) = test.t2.a) or isnull(test.t2.a)) and (test.t3.a = test.t2.a)) having <is_not_null_test>(test.t2.a) limit 1)) AS `t1.a in (select t2.a from t2,t3 where t3.a=t2.a)` from test.t1
drop table t1,t2,t3;
create table t1 (a float);
select 10.5 IN (SELECT * from t1 LIMIT 1);
......@@ -1168,9 +1168,9 @@ SELECT 0 IN (SELECT 1 FROM t1 a);
EXPLAIN EXTENDED SELECT 0 IN (SELECT 1 FROM t1 a);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL No tables used
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
Warnings:
Note 1003 select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a where isnull(1) having <is_not_null_test>(1) limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
Note 1003 select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a having <is_not_null_test>(1) limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
INSERT INTO t1 (pseudo) VALUES ('test1');
SELECT 0 IN (SELECT 1 FROM t1 a);
0 IN (SELECT 1 FROM t1 a)
......@@ -1178,9 +1178,9 @@ SELECT 0 IN (SELECT 1 FROM t1 a);
EXPLAIN EXTENDED SELECT 0 IN (SELECT 1 FROM t1 a);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL No tables used
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
Warnings:
Note 1003 select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a where isnull(1) having <is_not_null_test>(1) limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
Note 1003 select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a having <is_not_null_test>(1) limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
drop table t1;
CREATE TABLE `t1` (
`i` int(11) NOT NULL default '0',
......@@ -1312,7 +1312,7 @@ id select_type table type possible_keys key key_len ref rows Extra
2 DEPENDENT SUBQUERY t1 eq_ref PRIMARY PRIMARY 4 func 1 Using where
2 DEPENDENT SUBQUERY t3 eq_ref PRIMARY PRIMARY 4 test.t1.b 1 Using where; Using index
Warnings:
Note 1003 select high_priority test.t2.a AS `a` from test.t2 where <in_optimizer>(test.t2.a,<exists>(select 1 AS `Not_used` from test.t1 join test.t3 where ((test.t1.b = test.t3.a) and (<cache>(test.t2.a) = test.t1.a)) limit 1))
Note 1003 select high_priority test.t2.a AS `a` from test.t2 where <in_optimizer>(test.t2.a,<exists>(select 1 AS `Not_used` from test.t1 join test.t3 where ((<cache>(test.t2.a) = test.t1.a) and (test.t3.a = test.t1.b)) limit 1))
drop table t1, t2, t3;
create table t1 (a int, b int, index a (a,b));
create table t2 (a int, index a (a));
......@@ -1348,10 +1348,10 @@ a
explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 index NULL a 5 NULL 4 Using where; Using index
2 DEPENDENT SUBQUERY t3 index a a 5 NULL 3 Using index
2 DEPENDENT SUBQUERY t1 ref a a 10 func,test.t3.a 1000 Using where; Using index
2 DEPENDENT SUBQUERY t1 ref a a 5 func 1001 Using where; Using index
2 DEPENDENT SUBQUERY t3 index a a 5 NULL 3 Using where; Using index
Warnings:
Note 1003 select high_priority test.t2.a AS `a` from test.t2 where <in_optimizer>(test.t2.a,<exists>(select 1 AS `Not_used` from test.t1 join test.t3 where ((test.t1.b = test.t3.a) and (<cache>(test.t2.a) = test.t1.a)) limit 1))
Note 1003 select high_priority test.t2.a AS `a` from test.t2 where <in_optimizer>(test.t2.a,<exists>(select 1 AS `Not_used` from test.t1 join test.t3 where ((<cache>(test.t2.a) = test.t1.a) and (test.t3.a = test.t1.b)) limit 1))
insert into t1 values (3,31);
select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
a
......
......@@ -23,7 +23,7 @@ i @vv1:=if(sv1.i,1,0) @vv2:=if(sv2.i,1,0) @vv3:=if(sv3.i,1,0) @vv1+@vv2+@vv3
2 1 0 0 1
explain select * from t1 where i=@vv1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref i i 4 const 1 Using where
1 SIMPLE t1 ref i i 4 const 1
explain select * from t1 where @vv1:=@vv1+1 and i=@vv1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
......@@ -32,7 +32,7 @@ id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL i 4 NULL 3 Using where; Using index
explain select * from t1 where i=@vv1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref i i 4 const 1 Using where
1 SIMPLE t1 ref i i 4 const 1
drop table t1,t2;
set @a=0,@b=0;
select @a:=10, @b:=1, @a > @b, @a < @b;
......
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