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|
drop table if exists t1;
select (1,2,3) IN ((3,2,3), (1,2,3), (1,3,3));
(1,2,3) IN ((3,2,3), (1,2,3), (1,3,3))
1
select row(10,2,3) IN (row(3,2,3), row(1,2,3), row(1,3,3));
row(10,2,3) IN (row(3,2,3), row(1,2,3), row(1,3,3))
0
select row(1,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3));
row(1,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3))
1
select row(10,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3));
row(10,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3))
0
select row('a',1.5,3) IN (row(1,2,3), row('a',1.5,3), row('a','a','a'));
row('a',1.5,3) IN (row(1,2,3), row('a',1.5,3), row('a','a','a'))
1
Warnings:
Warning 1292 Truncated incorrect DECIMAL value: 'a'
Warning 1292 Truncated incorrect INTEGER value: 'a'
select row('a',0,3) IN (row(3,2,3), row('a','a','3'), row(1,3,3));
row('a',0,3) IN (row(3,2,3), row('a','a','3'), row(1,3,3))
1
Warnings:
Warning 1292 Truncated incorrect INTEGER value: 'a'
select row('a',0,3) IN (row(3,2,3), row('a','0','3'), row(1,3,3));
row('a',0,3) IN (row(3,2,3), row('a','0','3'), row(1,3,3))
1
select row('a',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3));
row('a',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3))
1
select row('b',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3));
row('b',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3))
0
select row('b',1.5,3) IN (row('b',NULL,3), row('a',1.5,3), row(1,3,3));
row('b',1.5,3) IN (row('b',NULL,3), row('a',1.5,3), row(1,3,3))
NULL
select row('b',1.5,3) IN (row('b',NULL,4), row('a',1.5,3), row(1,3,3));
row('b',1.5,3) IN (row('b',NULL,4), row('a',1.5,3), row(1,3,3))
0
select (1,2,(3,4)) IN ((3,2,(3,4)), (1,2,(3,4)));
(1,2,(3,4)) IN ((3,2,(3,4)), (1,2,(3,4)))
1
select row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,4));
ERROR 21000: Operand should contain 2 column(s)
select row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL)));
row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL)))
NULL
explain extended select row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL)));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select ((1,2,(3,4)) in ((3,2,(3,4)),(1,2,(3,NULL)))) AS `row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL)))`
SELECT (1,2,3)=(0,NULL,3);
(1,2,3)=(0,NULL,3)
0
SELECT (1,2,3)=(1,NULL,3);
(1,2,3)=(1,NULL,3)
NULL
SELECT (1,2,3)=(1,NULL,0);
(1,2,3)=(1,NULL,0)
0
SELECT ROW(1,2,3)=ROW(1,2,3);
ROW(1,2,3)=ROW(1,2,3)
1
SELECT ROW(2,2,3)=ROW(1+1,2,3);
ROW(2,2,3)=ROW(1+1,2,3)
1
SELECT ROW(1,2,3)=ROW(1+1,2,3);
ROW(1,2,3)=ROW(1+1,2,3)
0
SELECT ROW(1,2,3)<ROW(1+1,2,3);
ROW(1,2,3)<ROW(1+1,2,3)
1
SELECT ROW(1,2,3)>ROW(1+1,2,3);
ROW(1,2,3)>ROW(1+1,2,3)
0
SELECT ROW(1,2,3)<=ROW(1+1,2,3);
ROW(1,2,3)<=ROW(1+1,2,3)
1
SELECT ROW(1,2,3)>=ROW(1+1,2,3);
ROW(1,2,3)>=ROW(1+1,2,3)
0
SELECT ROW(1,2,3)<>ROW(1+1,2,3);
ROW(1,2,3)<>ROW(1+1,2,3)
1
SELECT ROW(NULL,2,3)=ROW(NULL,2,3);
ROW(NULL,2,3)=ROW(NULL,2,3)
NULL
SELECT ROW(NULL,2,3)<=>ROW(NULL,2,3);
ROW(NULL,2,3)<=>ROW(NULL,2,3)
1
SELECT ROW(1,2,ROW(3,4,5))=ROW(1,2,ROW(3,4,5));
ROW(1,2,ROW(3,4,5))=ROW(1,2,ROW(3,4,5))
1
SELECT ROW('test',2,3.33)=ROW('test',2,3.33);
ROW('test',2,3.33)=ROW('test',2,3.33)
1
SELECT ROW('test',2,3.33)=ROW('test',2,3.33,4);
ERROR 21000: Operand should contain 3 column(s)
SELECT ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,33));
ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,33))
1
SELECT ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,3));
ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,3))
0
SELECT ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,NULL));
ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,NULL))
NULL
SELECT ROW('test',2,ROW(3,33))=ROW('test',2,4);
ERROR 21000: Operand should contain 2 column(s)
create table t1 ( a int, b int, c int);
insert into t1 values (1,2,3), (2,3,1), (3,2,1), (1,2,NULL);
select * from t1 where ROW(1,2,3)=ROW(a,b,c);
a b c
1 2 3
select * from t1 where ROW(0,2,3)=ROW(a,b,c);
a b c
select * from t1 where ROW(1,2,3)<ROW(a,b,c);
a b c
2 3 1
3 2 1
select ROW(a,2,3) IN(row(1,b,c), row(2,3,1)) from t1;
ROW(a,2,3) IN(row(1,b,c), row(2,3,1))
1
0
0
NULL
select ROW(c,2,3) IN(row(1,b,a), row(2,3,1)) from t1;
ROW(c,2,3) IN(row(1,b,a), row(2,3,1))
0
0
1
NULL
select ROW(a,b,c) IN(row(1,2,3), row(3,2,1)) from t1;
ROW(a,b,c) IN(row(1,2,3), row(3,2,1))
1
0
1
NULL
select ROW(1,2,3) IN(row(a,b,c), row(1,2,3)) from t1;
ROW(1,2,3) IN(row(a,b,c), row(1,2,3))
1
1
1
1
drop table t1;
select ROW(1,1);
ERROR 21000: Operand should contain 1 column(s)
create table t1 (i int);
select 1 from t1 where ROW(1,1);
ERROR 21000: Operand should contain 1 column(s)
select count(*) from t1 order by ROW(1,1);
ERROR 21000: Operand should contain 1 column(s)
select count(*) from t1 having (1,1) order by i;
ERROR 21000: Operand should contain 1 column(s)
drop table t1;
create table t1 (a int, b int);
insert into t1 values (1, 4);
insert into t1 values (10, 40);
insert into t1 values (1, 4);
insert into t1 values (10, 43);
insert into t1 values (1, 4);
insert into t1 values (10, 41);
insert into t1 values (1, 4);
insert into t1 values (10, 43);
insert into t1 values (1, 4);
select a, MAX(b), (1, MAX(b)) = (1, 4) from t1 group by a;
a MAX(b) (1, MAX(b)) = (1, 4)
1 4 1
10 43 0
drop table t1;
SELECT ROW(2,10) <=> ROW(3,4);
ROW(2,10) <=> ROW(3,4)
0
SELECT ROW(NULL,10) <=> ROW(3,NULL);
ROW(NULL,10) <=> ROW(3,NULL)
0
SELECT ROW(1,ROW(2,3)) IN (ROW(1,ROW(2,3)),ROW(1,1));
ERROR 21000: Operand should contain 2 column(s)
SELECT ROW(1,ROW(2,3)) IN (ROW(1,ROW(2,3)),ROW(1,1),ROW(1,ROW(2,3)));
ERROR 21000: Operand should contain 2 column(s)
SELECT ROW(1,ROW(2,3)) IN (ROW(1,ROW(2,3)),ROW(1,ROW(2,2,2)));
ERROR 21000: Operand should contain 2 column(s)
SELECT ROW(1,ROW(2,3,4)) IN (ROW(1,ROW(2,3,4)),ROW(1,ROW(2,2)));
ERROR 21000: Operand should contain 3 column(s)
SELECT ROW(1,ROW(2,3)) IN (ROW(1,ROW(2,3)),(SELECT 1,1));
ERROR 21000: Operand should contain 2 column(s)
SELECT ROW(1,ROW(2,3)) IN (ROW(1,ROW(2,3)),(SELECT 1,1),ROW(1,ROW(2,4)));
ERROR 21000: Operand should contain 2 column(s)
SELECT ROW(1,ROW(2,3)) IN ((SELECT 1,1),ROW(1,ROW(2,3)));
ERROR 21000: Operand should contain 2 column(s)
SELECT ROW(2,1) IN (ROW(21,2),ROW(ROW(1,1,3),0));
ERROR 21000: Operand should contain 1 column(s)
SELECT ROW(2,1) IN (ROW(ROW(1,1,3),0),ROW(21,2));
ERROR 21000: Operand should contain 1 column(s)
CREATE TABLE t1(a int, b int, c int);
INSERT INTO t1 VALUES (1, 2, 3),
(NULL, 2, 3 ), (1, NULL, 3 ), (1, 2, NULL),
(NULL, 2, 3+1), (1, NULL, 3+1), (1, 2+1, NULL),
(NULL, 2, 3-1), (1, NULL, 3-1), (1, 2-1, NULL);
SELECT (1,2,3) = (1, NULL, 3);
(1,2,3) = (1, NULL, 3)
NULL
SELECT (1,2,3) = (1+1, NULL, 3);
(1,2,3) = (1+1, NULL, 3)
0
SELECT (1,2,3) = (1, NULL, 3+1);
(1,2,3) = (1, NULL, 3+1)
0
SELECT * FROM t1 WHERE (a,b,c) = (1,2,3);
a b c
1 2 3
SELECT (1,2,3) <> (1, NULL, 3);
(1,2,3) <> (1, NULL, 3)
NULL
SELECT (1,2,3) <> (1+1, NULL, 3);
(1,2,3) <> (1+1, NULL, 3)
1
SELECT (1,2,3) <> (1, NULL, 3+1);
(1,2,3) <> (1, NULL, 3+1)
1
SELECT * FROM t1 WHERE (a,b,c) <> (1,2,3);
a b c
NULL 2 4
1 NULL 4
1 3 NULL
NULL 2 2
1 NULL 2
1 1 NULL
SELECT (1,2,3) < (NULL, 2, 3);
(1,2,3) < (NULL, 2, 3)
NULL
SELECT (1,2,3) < (1, NULL, 3);
(1,2,3) < (1, NULL, 3)
NULL
SELECT (1,2,3) < (1-1, NULL, 3);
(1,2,3) < (1-1, NULL, 3)
0
SELECT (1,2,3) < (1+1, NULL, 3);
(1,2,3) < (1+1, NULL, 3)
1
SELECT * FROM t1 WHERE (a,b,c) < (1,2,3);
a b c
1 1 NULL
SELECT (1,2,3) <= (NULL, 2, 3);
(1,2,3) <= (NULL, 2, 3)
NULL
SELECT (1,2,3) <= (1, NULL, 3);
(1,2,3) <= (1, NULL, 3)
NULL
SELECT (1,2,3) <= (1-1, NULL, 3);
(1,2,3) <= (1-1, NULL, 3)
0
SELECT (1,2,3) <= (1+1, NULL, 3);
(1,2,3) <= (1+1, NULL, 3)
1
SELECT * FROM t1 WHERE (a,b,c) <= (1,2,3);
a b c
1 2 3
1 1 NULL
SELECT (1,2,3) > (NULL, 2, 3);
(1,2,3) > (NULL, 2, 3)
NULL
SELECT (1,2,3) > (1, NULL, 3);
(1,2,3) > (1, NULL, 3)
NULL
SELECT (1,2,3) > (1-1, NULL, 3);
(1,2,3) > (1-1, NULL, 3)
1
SELECT (1,2,3) > (1+1, NULL, 3);
(1,2,3) > (1+1, NULL, 3)
0
SELECT * FROM t1 WHERE (a,b,c) > (1,2,3);
a b c
1 3 NULL
SELECT (1,2,3) >= (NULL, 2, 3);
(1,2,3) >= (NULL, 2, 3)
NULL
SELECT (1,2,3) >= (1, NULL, 3);
(1,2,3) >= (1, NULL, 3)
NULL
SELECT (1,2,3) >= (1-1, NULL, 3);
(1,2,3) >= (1-1, NULL, 3)
1
SELECT (1,2,3) >= (1+1, NULL, 3);
(1,2,3) >= (1+1, NULL, 3)
0
SELECT * FROM t1 WHERE (a,b,c) >= (1,2,3);
a b c
1 2 3
1 3 NULL
DROP TABLE t1;
SELECT ROW(1,1,1) = ROW(1,1,1) as `1`, ROW(1,1,1) = ROW(1,2,1) as `0`, ROW(1,NULL,1) = ROW(2,2,1) as `0`, ROW(1,NULL,1) = ROW(1,2,2) as `0`, ROW(1,NULL,1) = ROW(1,2,1) as `null` ;
1 0 0 0 null
1 0 0 0 NULL
select row(NULL,1)=(2,0);
row(NULL,1)=(2,0)
0
CREATE TABLE t1 (a int, b int, PRIMARY KEY (a,b));
INSERT INTO t1 VALUES (1,1), (2,1), (3,1), (1,2), (3,2), (3,3);
EXPLAIN SELECT * FROM t1 WHERE a=3 AND b=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const PRIMARY PRIMARY 8 const,const 1 Using index
EXPLAIN SELECT * FROM t1 WHERE (a,b)=(3,2);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const PRIMARY PRIMARY 8 const,const 1 Using index
SELECT * FROM t1 WHERE a=3 and b=2;
a b
3 2
SELECT * FROM t1 WHERE (a,b)=(3,2);
a b
3 2
CREATE TABLE t2 (a int, b int, c int, PRIMARY KEY (a,b,c));
INSERT INTO t2 VALUES
(1,1,2), (3,1,3), (1,2,2), (4,4,2),
(1,1,1), (3,1,1), (1,2,1);
EXPLAIN SELECT * FROM t1,t2 WHERE t1.a=t2.a AND t1.b=t2.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 6 Using index
1 SIMPLE t2 ref PRIMARY PRIMARY 8 test.t1.a,test.t1.b 1 Using index
EXPLAIN SELECT * FROM t1,t2 WHERE (t1.a,t1.b)=(t2.a,t2.b);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 6 Using index
1 SIMPLE t2 ref PRIMARY PRIMARY 8 test.t1.a,test.t1.b 1 Using index
SELECT * FROM t1,t2 WHERE t1.a=t2.a and t1.b=t2.b;
a b a b c
1 1 1 1 1
1 1 1 1 2
1 2 1 2 1
1 2 1 2 2
3 1 3 1 1
3 1 3 1 3
SELECT * FROM t1,t2 WHERE (t1.a,t1.b)=(t2.a,t2.b);
a b a b c
1 1 1 1 1
1 1 1 1 2
1 2 1 2 1
1 2 1 2 2
3 1 3 1 1
3 1 3 1 3
EXPLAIN SELECT * FROM t1,t2 WHERE t1.a=t2.a AND t1.b=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 5 Using where; Using index
1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a 1 Using index
EXPLAIN SELECT * FROM t1,t2 WHERE (t1.a,t1.b)=(t2.a,2);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 5 Using where; Using index
1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a 1 Using index
SELECT * FROM t1,t2 WHERE t1.a=1 and t1.b=t2.b;
a b a b c
1 1 1 1 2
1 1 3 1 3
1 2 1 2 2
1 1 1 1 1
1 1 3 1 1
1 2 1 2 1
SELECT * FROM t1,t2 WHERE (t1.a,t1.b)=(t2.a,2);
a b a b c
1 2 1 1 1
1 2 1 1 2
1 2 1 2 1
1 2 1 2 2
3 2 3 1 1
3 2 3 1 3
EXPLAIN EXTENDED SELECT * FROM t1,t2 WHERE (t1.a,t1.b)=(t2.a,t2.b+1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 6 Using index
1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a 1 Using where; Using index
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where ((`test`.`t2`.`a` = `test`.`t1`.`a`) and (`test`.`t1`.`b` = (`test`.`t2`.`b` + 1)))
SELECT * FROM t1,t2 WHERE (t1.a,t1.b)=(t2.a,t2.b+1);
a b a b c
1 2 1 1 1
1 2 1 1 2
3 2 3 1 1
3 2 3 1 3
EXPLAIN EXTENDED SELECT * FROM t1,t2 WHERE (t1.a-1,t1.b)=(t2.a-1,t2.b+1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 8 NULL 6 Using index
1 SIMPLE t2 index NULL PRIMARY 12 NULL 7 Using where; Using index
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where (((`test`.`t1`.`a` - 1) = (`test`.`t2`.`a` - 1)) and (`test`.`t1`.`b` = (`test`.`t2`.`b` + 1)))
SELECT * FROM t1,t2 WHERE (t1.a-1,t1.b)=(t2.a-1,t2.b+1);
a b a b c
1 2 1 1 2
3 2 3 1 3
1 2 1 1 1
3 2 3 1 1
EXPLAIN SELECT * FROM t2 WHERE a=3 AND b=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref PRIMARY PRIMARY 8 const,const 1 Using index
EXPLAIN SELECT * FROM t2 WHERE (a,b)=(3,2);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref PRIMARY PRIMARY 8 const,const 1 Using index
SELECT * FROM t2 WHERE a=3 and b=2;
a b c
SELECT * FROM t2 WHERE (a,b)=(3,2);
a b c
EXPLAIN SELECT * FROM t1,t2 WHERE t2.a=t1.a AND t2.b=2 AND t2.c=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 6 Using index
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 12 test.t1.a,const,const 1 Using index
EXPLAIN EXTENDED SELECT * FROM t1,t2 WHERE (t2.a,(t2.b,t2.c))=(t1.a,(2,1));
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 6 Using index
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 12 test.t1.a,const,const 1 Using index
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where ((`test`.`t2`.`c` = 1) and (`test`.`t2`.`b` = 2) and (`test`.`t2`.`a` = `test`.`t1`.`a`))
SELECT * FROM t1,t2 WHERE (t2.a,(t2.b,t2.c))=(t1.a,(2,1));
a b a b c
1 1 1 2 1
1 2 1 2 1
EXPLAIN EXTENDED SELECT * FROM t1,t2 WHERE t2.a=t1.a AND (t2.b,t2.c)=(2,1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 6 Using index
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 12 test.t1.a,const,const 1 Using index
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where ((`test`.`t2`.`c` = 1) and (`test`.`t2`.`b` = 2) and (`test`.`t2`.`a` = `test`.`t1`.`a`))
SELECT * FROM t1,t2 WHERE t2.a=t1.a AND (t2.b,t2.c)=(2,1);
a b a b c
1 1 1 2 1
1 2 1 2 1
DROP TABLE t1,t2;
CREATE TABLE t1(
a int, b int, c int, d int, e int, f int, g int, h int,
PRIMARY KEY (a,b,c,d,e,f,g)
);
INSERT INTO t1 VALUES (1,2,3,4,5,6,7,99);
SELECT h FROM t1 WHERE (a,b,c,d,e,f,g)=(1,2,3,4,5,6,7);
h
99
SET @x:= (SELECT h FROM t1 WHERE (a,b,c,d,e,f,g)=(1,2,3,4,5,6,7));
SELECT @x;
@x
99
DROP TABLE t1;
CREATE TABLE t1 (a INT, b INT);
INSERT INTO t1 VALUES (1,1);
SELECT ROW(a, 1) IN (SELECT SUM(b), 1) FROM t1 GROUP BY a;
ROW(a, 1) IN (SELECT SUM(b), 1)
1
SELECT ROW(a, 1) IN (SELECT SUM(b), 3) FROM t1 GROUP BY a;
ROW(a, 1) IN (SELECT SUM(b), 3)
0
DROP TABLE t1;
create table t1 (a varchar(200),
b int unsigned not null primary key auto_increment)
default character set 'utf8';
create table t2 (c varchar(200),
d int unsigned not null primary key auto_increment)
default character set 'latin1';
insert into t1 (a) values('abc');
insert into t2 (c) values('abc');
select * from t1,t2 where (a,b) = (c,d);
a b c d
abc 1 abc 1
select host,user from mysql.user where (host,user) = ('localhost','test');
host user
drop table t1,t2;
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