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|
drop table if exists t1,t2;
set @a := foo;
ERROR 42S22: Unknown column 'foo' in 'field list'
set @a := connection_id() + 3;
select @a - connection_id();
@a - connection_id()
3
set @b := 1;
select @b;
@b
1
CREATE TABLE t1 ( i int not null, v int not null,index (i));
insert into t1 values (1,1),(1,3),(2,1);
create table t2 (i int not null, unique (i));
insert into t2 select distinct i from t1;
select * from t2;
i
1
2
select distinct t2.i,@vv1:=if(sv1.i,1,0),@vv2:=if(sv2.i,1,0),@vv3:=if(sv3.i,1,0), @vv1+@vv2+@vv3 from t2 left join t1 as sv1 on sv1.i=t2.i and sv1.v=1 left join t1 as sv2 on sv2.i=t2.i and sv2.v=2 left join t1 as sv3 on sv3.i=t2.i and sv3.v=3;
i @vv1:=if(sv1.i,1,0) @vv2:=if(sv2.i,1,0) @vv3:=if(sv3.i,1,0) @vv1+@vv2+@vv3
1 1 0 1 2
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
select @vv1,i,v from t1 where i=@vv1;
@vv1 i v
1 1 1
1 1 3
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
explain select @vv1:=i from t1 where i=@vv1;
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
drop table t1,t2;
set @a=0,@b=0;
select @a:=10, @b:=1, @a > @b, @a < @b;
@a:=10 @b:=1 @a > @b @a < @b
10 1 1 0
select @a:="10", @b:="1", @a > @b, @a < @b;
@a:="10" @b:="1" @a > @b @a < @b
10 1 1 0
select @a:=10, @b:=2, @a > @b, @a < @b;
@a:=10 @b:=2 @a > @b @a < @b
10 2 0 1
select @a:="10", @b:="2", @a > @b, @a < @b;
@a:="10" @b:="2" @a > @b @a < @b
10 2 1 0
select @a:=1;
@a:=1
1
select @a, @a:=1;
@a @a:=1
1 1
create table t1 (id int, d double, c char(10));
insert into t1 values (1,2.0, "test");
select @c:=0;
@c:=0
0
update t1 SET id=(@c:=@c+1);
select @c;
@c
1
select @c:=0;
@c:=0
0
update t1 set id=(@c:=@c+1);
select @c;
@c
1
select @c:=0;
@c:=0
0
select @c:=@c+1;
@c:=@c+1
1
select @d,(@d:=id),@d from t1;
@d (@d:=id) @d
NULL 1 1
select @e,(@e:=d),@e from t1;
@e (@e:=d) @e
NULL 2 2
select @f,(@f:=c),@f from t1;
@f (@f:=c) @f
NULL test test
set @g=1;
select @g,(@g:=c),@g from t1;
@g (@g:=c) @g
1 test 0
select @c, @d, @e, @f;
@c @d @e @f
1 1 2 test
select @d:=id, @e:=id, @f:=id, @g:=@id from t1;
@d:=id @e:=id @f:=id @g:=@id
1 1 1 NULL
select @c, @d, @e, @f, @g;
@c @d @e @f @g
1 1 1 1 NULL
drop table t1;
select @a:=10, @b:=2, @a>@b, @a:="10", @b:="2", @a>@b, @a:=10, @b:=2, @a>@b, @a:="10", @b:="2", @a>@b;
@a:=10 @b:=2 @a>@b @a:="10" @b:="2" @a>@b @a:=10 @b:=2 @a>@b @a:="10" @b:="2" @a>@b
10 2 1 10 2 1 10 2 1 10 2 1
create table t1 (i int not null);
insert t1 values (1),(2),(2),(3),(3),(3);
select @a:=0;
@a:=0
0
select @a, @a:=@a+count(*), count(*), @a from t1 group by i;
@a @a:=@a+count(*) count(*) @a
0 1 1 0
0 2 2 0
0 3 3 0
select @a:=0;
@a:=0
0
select @a+0, @a:=@a+0+count(*), count(*), @a+0 from t1 group by i;
@a+0 @a:=@a+0+count(*) count(*) @a+0
0 1 1 0
1 3 2 0
3 6 3 0
set @a=0;
select @a,@a:="hello",@a,@a:=3,@a,@a:="hello again" from t1 group by i;
@a @a:="hello" @a @a:=3 @a @a:="hello again"
0 hello 0 3 0 hello again
0 hello 0 3 0 hello again
0 hello 0 3 0 hello again
select @a,@a:="hello",@a,@a:=3,@a,@a:="hello again" from t1 group by i;
@a @a:="hello" @a @a:=3 @a @a:="hello again"
hello again hello hello again 3 hello again hello again
hello again hello hello again 3 hello again hello again
hello again hello hello again 3 hello again hello again
drop table t1;
set @a='test';
select collation(@a),coercibility(@a);
collation(@a) coercibility(@a)
utf8_general_ci 2
select @a='TEST';
@a='TEST'
1
select @a='TEST' collate utf8_bin;
@a='TEST' collate utf8_bin
0
set @a='test' collate utf8_general_ci;
select collation(@a),coercibility(@a);
collation(@a) coercibility(@a)
utf8_general_ci 2
select @a='TEST';
@a='TEST'
1
select @a='TEST' collate utf8_bin;
@a='TEST' collate utf8_bin
0
select collation(@a:='test');
collation(@a:='test')
utf8_general_ci
select coercibility(@a:='test');
coercibility(@a:='test')
2
select collation(@a:='test' collate utf8_bin);
collation(@a:='test' collate utf8_bin)
utf8_bin
select coercibility(@a:='test' collate utf8_bin);
coercibility(@a:='test' collate utf8_bin)
2
select (@a:='test' collate utf8_bin) = 'TEST';
(@a:='test' collate utf8_bin) = 'TEST'
0
select collation(@a),coercibility(@a);
collation(@a) coercibility(@a)
utf8_bin 2
select (@a:='test' collate utf8_bin) = 'TEST' collate utf8_general_ci;
(@a:='test' collate utf8_bin) = 'TEST' collate utf8_general_ci
1
set @var= NULL ;
select FIELD( @var,'1it','Hit') as my_column;
my_column
0
select @v, coercibility(@v);
@v coercibility(@v)
NULL 2
set @v1=null, @v2=1, @v3=1.1, @v4=now();
select coercibility(@v1),coercibility(@v2),coercibility(@v3),coercibility(@v4);
coercibility(@v1) coercibility(@v2) coercibility(@v3) coercibility(@v4)
2 2 2 2
set session @honk=99;
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle server version for the right syntax to use near '@honk=99' at line 1
select @@local.max_allowed_packet;
@@local.max_allowed_packet
#
select @@session.max_allowed_packet;
@@session.max_allowed_packet
#
select @@global.max_allowed_packet;
@@global.max_allowed_packet
#
select @@max_allowed_packet;
@@max_allowed_packet
#
select @@Max_Allowed_Packet;
@@Max_Allowed_Packet
#
select @@version;
@@version
#
select @@global.version;
@@global.version
#
End of 4.1 tests
set @first_var= NULL;
create table t1 select @first_var;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`@first_var` blob
) ENGINE=DEFAULT
drop table t1;
set @first_var= cast(NULL as integer);
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle server version for the right syntax to use near 'integer)' at line 1
set @first_var= NULL;
create table t1 select @first_var;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`@first_var` blob
) ENGINE=DEFAULT
drop table t1;
set @first_var= concat(NULL);
create table t1 select @first_var;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`@first_var` blob
) ENGINE=DEFAULT
drop table t1;
set @first_var=1;
set @first_var= cast(NULL as CHAR);
create table t1 select @first_var;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`@first_var` text
) ENGINE=DEFAULT
drop table t1;
set @a=18446744071710965857;
select @a;
@a
18446744071710965857
CREATE TABLE `bigfailure` (
`afield` BIGINT NOT NULL
);
INSERT INTO `bigfailure` VALUES (18446744071710965857);
SELECT * FROM bigfailure;
afield
-1998585759
select * from (SELECT afield FROM bigfailure) as b;
afield
-1998585759
select * from bigfailure where afield = (SELECT afield FROM bigfailure);
afield
-1998585759
select * from bigfailure where afield = 18446744071710965857;
afield
-1998585759
select * from bigfailure where afield = '18446744071710965857';
afield
select * from bigfailure where afield = 18446744071710965856+1;
afield
-1998585759
SET @a := (SELECT afield FROM bigfailure);
SELECT @a;
@a
-1998585759
SET @a := (select afield from (SELECT afield FROM bigfailure) as b);
SELECT @a;
@a
-1998585759
SET @a := (select * from bigfailure where afield = (SELECT afield FROM bigfailure));
SELECT @a;
@a
-1998585759
drop table bigfailure;
create table t1(f1 int, f2 int);
insert into t1 values (1,2),(2,3),(3,1);
select @var:=f2 from t1 group by f1 order by f2 desc limit 1;
@var:=f2
3
select @var;
@var
3
drop table t1;
insert into city 'blah';
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your Drizzle server version for the right syntax to use near ''blah'' at line 1
SHOW COUNT(*) WARNINGS;
@@session.warning_count
1
SHOW COUNT(*) ERRORS;
@@session.error_count
1
create table t1(f1 int, f2 varchar(2), f3 float, f4 decimal(2,1));
insert into t1 values
(1, "a", 1.5, 1.6), (1, "a", 1.5, 1.6), (2, "b", 2.5, 2.6),
(3, "c", 3.5, 3.6), (4, "d", 4.5, 4.6), (1, "a", 1.5, 1.6),
(3, "c", 3.5, 3.6), (1, "a", 1.5, 1.6);
select @a:=f1, count(f1) from t1 group by 1 desc;
@a:=f1 count(f1)
4 1
3 2
2 1
1 4
select @a:=f1, count(f1) from t1 group by 1 asc;
@a:=f1 count(f1)
1 4
2 1
3 2
4 1
select @a:=f2, count(f2) from t1 group by 1 desc;
@a:=f2 count(f2)
d 1
c 2
b 1
a 4
select @a:=f3, count(f3) from t1 group by 1 desc;
@a:=f3 count(f3)
4.5 1
3.5 2
2.5 1
1.5 4
select @a:=f4, count(f4) from t1 group by 1 desc;
@a:=f4 count(f4)
4.6 1
3.6 2
2.6 1
1.6 4
drop table t1;
create table t1 (f1 int);
insert into t1 values (2), (1);
select @i := f1 as j from t1 order by 1;
j
1
2
drop table t1;
create table t1(a int);
insert into t1 values(5),(4),(4),(3),(2),(2),(2),(1);
set @rownum := 0;
set @rank := 0;
set @prev_score := NULL;
select @rownum := @rownum + 1 as row,
@rank := IF(@prev_score!=a, @rownum, @rank) as rank,
@prev_score := a as score
from t1 order by score desc;
drop table t1;
End of 5.1 tests
|