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DROP TABLE IF EXISTS t1;
SELECT IF(NULL AND 1, 1, 2), IF(1 AND NULL, 1, 2);
IF(NULL AND 1, 1, 2) IF(1 AND NULL, 1, 2)
2 2
SELECT NULL AND 1, 1 AND NULL, 0 AND NULL, NULL and 0;
NULL AND 1 1 AND NULL 0 AND NULL NULL and 0
NULL NULL 0 0
create table t1 (a int);
insert into t1 values (0),(1),(NULL);
SELECT * FROM t1 WHERE IF(a AND 1, 0, 1);
a
0
NULL
SELECT * FROM t1 WHERE IF(1 AND a, 0, 1);
a
0
NULL
SELECT * FROM t1 where NOT(a AND 1);
a
0
SELECT * FROM t1 where NOT(1 AND a);
a
0
SELECT * FROM t1 where (a AND 1)=0;
a
0
SELECT * FROM t1 where (1 AND a)=0;
a
0
SELECT * FROM t1 where (1 AND a)=1;
a
1
SELECT * FROM t1 where (1 AND a) IS NULL;
a
NULL
SET @a=0, @b=0;
SELECT * FROM t1 WHERE NULL AND (@a:=@a+1);
a
SELECT * FROM t1 WHERE NOT(a>=0 AND NULL AND (@b:=@b+1));
a
SELECT * FROM t1 WHERE a=2 OR (NULL AND (@a:=@a+1));
a
SELECT * FROM t1 WHERE NOT(a=2 OR (NULL AND (@b:=@b+1)));
a
SELECT @a, @b;
@a @b
0 6
DROP TABLE t1;
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