set @a := foo; ERROR42S22: Unknown column 'foo' in 'SET' 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 11012 21001
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 2
select @vv1,i,v from t1 where i=@vv1;
@vv1 i v 111 113
explain select * from t1 where @vv1:=@vv1+1and 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 2
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 10110
select @a:="10", @b:="1", @a > @b, @a < @b;
@a:="10" @b:="1" @a > @b @a < @b 10110
select @a:=10, @b:=2, @a > @b, @a < @b;
@a:=10 @b:=2 @a > @b @a < @b 10201
select @a:="10", @b:="2", @a > @b, @a < @b;
@a:="10" @b:="2" @a > @b @a < @b 10210
select @a:=1;
@a:=1 1
select @a, @a:=1;
@a @a:=1 11
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 11
select @e,(@e:=d),@e from t1;
@e (@e:=d) @e
NULL 22
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 112 test
select @d:=id, @e:=id, @f:=id, @g:=@id from t1;
@d:=id @e:=id @f:=id @g:=@id 111 NULL
select @c, @d, @e, @f, @g;
@c @d @e @f @g 1111 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 1021102110211021
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 0110 0220 0330
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 0110 0220 0330 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 030 hello again 0 hello 030 hello again 0 hello 030 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=_latin2'test';
select charset(@a),collation(@a),coercibility(@a);
charset(@a) collation(@a) coercibility(@a)
latin2 latin2_general_ci 5
select @a=_latin2'TEST';
@a=_latin2'TEST' 1
select @a=_latin2'TEST' collate latin2_bin;
@a=_latin2'TEST' collate latin2_bin 0 set @a=_latin2'test' collate latin2_general_ci;
select charset(@a),collation(@a),coercibility(@a);
charset(@a) collation(@a) coercibility(@a)
latin2 latin2_general_ci 5
select @a=_latin2'TEST';
@a=_latin2'TEST' 1
select @a=_latin2'TEST' collate latin2_bin;
@a=_latin2'TEST' collate latin2_bin 0
select charset(@a:=_latin2'test');
charset(@a:=_latin2'test')
latin2
select collation(@a:=_latin2'test');
collation(@a:=_latin2'test')
latin2_general_ci
select coercibility(@a:=_latin2'test');
coercibility(@a:=_latin2'test') 6
select collation(@a:=_latin2'test' collate latin2_bin);
collation(@a:=_latin2'test' collate latin2_bin)
latin2_bin
select coercibility(@a:=_latin2'test' collate latin2_bin);
coercibility(@a:=_latin2'test' collate latin2_bin) 6
select (@a:=_latin2'test' collate latin2_bin) = _latin2'TEST';
(@a:=_latin2'test' collate latin2_bin) = _latin2'TEST' 0
select charset(@a),collation(@a),coercibility(@a);
charset(@a) collation(@a) coercibility(@a)
latin2 latin2_bin 5
select (@a:=_latin2'test' collate latin2_bin) = _latin2'TEST' collate latin2_general_ci;
(@a:=_latin2'test' collate latin2_bin) = _latin2'TEST' collate latin2_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 5 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) 5775 set session @honk=99; ERROR42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB 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` longblob DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
drop table t1; set @first_var= cast(NULL as signed integer);
create table t1 select @first_var;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`@first_var` bigint(20) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
drop table t1; set @first_var= NULL;
create table t1 select @first_var;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`@first_var` bigint(20) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
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` longblob DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
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` longtext CHARACTER SET latin1 COLLATE latin1_swedish_ci DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
drop table t1; set @a=18446744071710965857;
select @a;
@a 18446744071710965857
CREATE TABLE `bigfailure` (
`afield` BIGINT UNSIGNED NOT NULL
);
INSERT INTO `bigfailure` VALUES (18446744071710965857);
SELECT * FROM bigfailure;
afield 18446744071710965857
select * from (SELECT afield FROM bigfailure) as b;
afield 18446744071710965857
select * from bigfailure where afield = (SELECT afield FROM bigfailure);
afield 18446744071710965857
select * from bigfailure where afield = 18446744071710965857;
afield 18446744071710965857
select * from bigfailure where afield = 18446744071710965856+1;
afield 18446744071710965857 SET @a := (SELECT afield FROM bigfailure);
SELECT @a;
@a 18446744071710965857 SET @a := (select afield from (SELECT afield FROM bigfailure) as b);
SELECT @a;
@a 18446744071710965857 SET @a := (select * from bigfailure where afield = (SELECT afield FROM bigfailure));
SELECT @a;
@a 18446744071710965857
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
create table t2 as select @var:=f2 from t1 group by f1 order by f2 desc limit 1;
select * from t2;
@var:=f2 3
select @var;
@var 3
drop table t1,t2;
insert into city 'blah'; ERROR42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB 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) 41 32 21 14
select @a:=f1, count(f1) from t1 group by 1 asc;
@a:=f1 count(f1) 14 21 32 41
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) 4.51 3.52 2.51 1.54
select @a:=f4, count(f4) from t1 group by 1 desc;
@a:=f4 count(f4) 4.61 3.62 2.61 1.64
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;
create table t1(b bigint);
insert into t1 (b) values (10), (30), (10), (10); set @var := 0;
explain select if(b=@var, 999, b) , @var := b from t1 order by b;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using filesort set @var := 0;
select if(b=@var, 999, b) , @var := b from t1 order by b; if(b=@var, 999, b) @var := b 1010 3030 99910 99910
drop table t1;
create temporary table t1 (id int);
insert into t1 values (2), (3), (3), (4); set @lastid=-1;
select @lastid != id, @lastid, @lastid := id from t1;
@lastid != id @lastid @lastid := id 1 -12 123 033 134
drop table t1;
create temporary table t1 (id bigint);
insert into t1 values (2), (3), (3), (4); set @lastid=-1;
select @lastid != id, @lastid, @lastid := id from t1;
@lastid != id @lastid @lastid := id 1 -12 123 033 134
drop table t1;
CREATE TABLE t1(a INT, b INT);
INSERT INTO t1 VALUES (0, 0), (2, 1), (2, 3), (1, 1), (30, 20);
SELECT a, b INTO @a, @b FROM t1 WHERE a=2AND b=3 GROUP BY a, b;
SELECT @a, @b;
@a @b 23
SELECT a, b FROM t1 WHERE a=2AND b=3 GROUP BY a, b;
a b 23
DROP TABLE t1;
CREATE TABLE t1 (f1 int(11) default NULL, f2 int(11) default NULL);
CREATE TABLE t2 (f1 int(11) default NULL, f2 int(11) default NULL, foo int(11));
CREATE TABLE t3 (f1 int(11) default NULL, f2 int(11) default NULL);
INSERT INTO t1 VALUES(10, 10);
INSERT INTO t1 VALUES(10, 10);
INSERT INTO t2 VALUES(10, 10, 10);
INSERT INTO t2 VALUES(10, 10, 10);
INSERT INTO t3 VALUES(10, 10);
INSERT INTO t3 VALUES(10, 10);
SELECT MIN(t2.f1),
@bar:= (SELECT MIN(t3.f2) FROM t3 WHERE t3.f2 > foo)
FROM t1,t2 WHERE t1.f1 = t2.f1 ORDER BY t2.f1; MIN(t2.f1) @bar:= (SELECT MIN(t3.f2) FROM t3 WHERE t3.f2 > foo) 10 NULL
DROP TABLE t1, t2, t3;
End of 5.0 tests
CREATE TABLE t1 (i INT);
CREATE TRIGGER t_after_insert AFTER INSERT ON t1 FOR EACH ROW SET @bug42188 = 10;
INSERT INTO t1 VALUES (1);
change_user root,,test;
INSERT INTO t1 VALUES (1);
DROP TABLE t1;
CREATE TABLE t1(a INT);
INSERT INTO t1 VALUES (0),(0);
# BUG#55615 : should not crash
SELECT (@a:=(SELECT @a:=1 FROM t1 LIMIT 1)) AND COUNT(1) FROM t1 GROUP BY @a;
(@a:=(SELECT @a:=1 FROM t1 LIMIT 1)) AND COUNT(1) 1 1
# BUG#55564 : should not crash
SELECT IF(
@v:=LEAST((SELECT 1 FROM t1 t2 LEFT JOIN t1 ON (@v) GROUP BY t1.a), a),
count(*), 1)
FROM t1 GROUP BY a LIMIT 1; IF(
@v:=LEAST((SELECT 1 FROM t1 t2 LEFT JOIN t1 ON (@v) GROUP BY t1.a), a),
count(*), 1) 1
DROP TABLE t1;
select @v:=@v:=sum(1) from dual;
@v:=@v:=sum(1) 1
CREATE TABLE t1(a DECIMAL(31,21));
INSERT INTO t1 VALUES (0);
SELECT (@v:=a) <> (@v:=1) FROM t1;
(@v:=a) <> (@v:=1) 1
DROP TABLE t1;
CREATE TABLE t1(a int);
INSERT INTO t1 VALUES (1), (2);
SELECT DISTINCT @a:=MIN(t1.a) FROM t1, t1 AS t2
GROUP BY @b:=(SELECT COUNT(*) > t2.a);
@a:=MIN(t1.a) 1
DROP TABLE t1; SET @bug12408412=1;
SELECT GROUP_CONCAT(@bug12408412 ORDER BY 1) INTO @bug12408412;
End of 5.1 tests
CREATE TABLE t1(a INT);
INSERT INTO t1 VALUES (0);
SELECT DISTINCT POW(COUNT(*), @a:=(SELECT 1 FROM t1 LEFT JOIN t1 AS t2 ON @a))
AS b FROM t1 GROUP BY a;
b 1
SELECT @a;
@a 1
DROP TABLE t1;
CREATE TABLE t1(f1 INT, f2 INT);
INSERT INTO t1 VALUES (1,2),(2,3),(3,1);
CREATE TABLE t2(a INT);
INSERT INTO t2 VALUES (1); SET @var=NULL;
SELECT @var:=(SELECT f2 FROM t2 WHERE @var) FROM t1 GROUP BY f1 ORDER BY f2 DESC
LIMIT 1;
@var:=(SELECT f2 FROM t2 WHERE @var)
NULL
SELECT @var;
@var
NULL
DROP TABLE t1, t2;
CREATE TABLE t1(a INT);
INSERT INTO t1 VALUES (0),(1),(3);
SELECT DISTINCT POW(COUNT(distinct a), @a:=(SELECT 1 FROM t1 LEFT JOIN t1 AS t2 ON @a limit 1)) AS b FROM t1 GROUP BY a;
b 1
SELECT @a;
@a 1
DROP TABLE t1;
End of 5.2 tests
CREATE TABLE t1(f1 INT AUTO_INCREMENT, PRIMARY KEY(f1));
INSERT INTO t1 SET f1 = NULL ; SET @aux = NULL ;
INSERT INTO t1 SET f1 = @aux ; SET @aux1 = 0.123E-1; SET @aux1 = NULL;
INSERT INTO t1 SET f1 = @aux1 ;
SELECT * FROM t1;
f1 1 2 3
DROP TABLE t1;
CREATE TABLE t1(f1 VARCHAR(257) , f2 INT, PRIMARY KEY(f2));
CREATE TRIGGER trg1 BEFORE INSERT ON t1 FOR EACH ROW SET @aux = 1; SET @aux = 1; SET @aux = NULL;
INSERT INTO test.t1 (f1, f2) VALUES (1, 1), (@aux, 2); SET @aux = 'text'; SET @aux = NULL;
INSERT INTO t1(f1, f2) VALUES (1, 3), (@aux, 4);
SELECT f1, f2 FROM t1 ORDER BY f2;
f1 f2 11 12 13 14
DROP TRIGGER trg1;
DROP TABLE t1;
#
# Bug #12408412: GROUP_CONCAT + ORDER BY + INPUT/OUTPUT
# SAME USER VARIABLE = CRASH
# SET @bug12408412=1;
SELECT GROUP_CONCAT(@bug12408412 ORDER BY 1) INTO @bug12408412;
CREATE TABLE t1(a INT);
INSERT INTO t1 VALUES (0);
SELECT DISTINCT POW(COUNT(*), @a:=(SELECT 1 FROM t1 LEFT JOIN t1 AS t2 ON @a))
AS b FROM t1 GROUP BY a;
b 1
SELECT @a;
@a 1
DROP TABLE t1;
CREATE TABLE t1(f1 INT, f2 INT);
INSERT INTO t1 VALUES (1,2),(2,3),(3,1);
CREATE TABLE t2(a INT);
INSERT INTO t2 VALUES (1); SET @var=NULL;
SELECT @var:=(SELECT f2 FROM t2 WHERE @var) FROM t1 GROUP BY f1 ORDER BY f2 DESC
LIMIT 1;
@var:=(SELECT f2 FROM t2 WHERE @var)
NULL
SELECT @var;
@var
NULL
DROP TABLE t1, t2;
CREATE TABLE t1(a INT);
INSERT INTO t1 VALUES (0),(1),(3);
SELECT DISTINCT POW(COUNT(distinct a), @a:=(SELECT 1 FROM t1 LEFT JOIN t1 AS t2 ON @a limit 1)) AS b FROM t1 GROUP BY a;
b 1
SELECT @a;
@a 1
DROP TABLE t1;
# End of 5.5 tests
#
# Check that used memory extends if we set a variable
# set @var= repeat('a',30000); 1
explain select @a:=max(seq) from seq_1_to_1000000;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
#
# Start of 10.3 tests
#
#
# MDEV-12859 Out-of-range error for CREATE..SELECT @a:=EXTRACT(MINUTE_MICROSECOND FROM..
# SET sql_mode=STRICT_ALL_TABLES;
CREATE ORREPLACE TABLE t1 AS
SELECT @a:=EXTRACT(MINUTE_MICROSECOND FROM '2001-01-01 11:22:33.999999') AS c1;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c1` bigint(11) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
SELECT * FROM t1;
c1 2233999999
DROP TABLE t1; SET sql_mode=DEFAULT;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.15 Sekunden
(vorverarbeitet am 2026-10-08)
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