SELECT (1,2,3)=(1,2,3);
(1,2,3)=(1,2,3)
1
SELECT (2,2,3)=(1+1,2,3);
(2,2,3)=(1+1,2,3)
1
SELECT (1,2,3)=(1+1,2,3);
(1,2,3)=(1+1,2,3)
0
SELECT (1,2,3)<(1+1,2,3);
(1,2,3)<(1+1,2,3)
1
SELECT (1,2,3)>(1+1,2,3);
(1,2,3)>(1+1,2,3)
0
SELECT (1,2,3)<=(1+1,2,3);
(1,2,3)<=(1+1,2,3)
1
SELECT (1,2,3)>=(1+1,2,3);
(1,2,3)>=(1+1,2,3)
0
SELECT (1,2,3)<>(1+1,2,3);
(1,2,3)<>(1+1,2,3)
1
SELECT (NULL,2,3)=(NULL,2,3);
(NULL,2,3)=(NULL,2,3)
NULL
SELECT (NULL,2,3)<=>(NULL,2,3);
(NULL,2,3)<=>(NULL,2,3)
1
SELECT (1,2,(3,4,5))=(1,2,(3,4,5));
(1,2,(3,4,5))=(1,2,(3,4,5))
1
SELECT ('test',2,3.33)=('test',2,3.33);
('test',2,3.33)=('test',2,3.33)
1
SELECT ('test',2,3.33)=('test',2,3.33,4);
Cardinality error (more/less than 3 columns)
drop table if exists t1;
create table t1 ( a int, b int, c int);
insert into t1 values (1,2,3), (2,3,1), (3,2,1);
select * from t1 where (1,2,3)=(a,b,c);
a	b	c
1	2	3
select * from t1 where (0,2,3)=(a,b,c);
a	b	c
select * from t1 where (1,2,3)<(a,b,c);
a	b	c
2	3	1
3	2	1
drop table t1;
select (1,1);
Cardinality error (more/less than 1 columns)
drop table if exists t1;
create table t1 (i int);
select 1 from t1 where (1,1);
Cardinality error (more/less than 1 columns)
select count(*) from t1 order by (1,1);
Cardinality error (more/less than 1 columns)
drop table t1;