select 123 + 543, 321 * 5, -456 / 2, 10 % 3, 2 / 0, 3 % 0;
- 比较运算符
select 1=2, 2<3, 3<=4, 4>5, 5>=3, 8!=9, 8<>9, 'abc' =
'Abc', 'z' > 'a';
select 123 between 100 and 200, 'b' in ('a', 'b', 'c');
/* 输出
+-------------------------+------------------------+
| 123 between 100 and 200 | 'b' in ('a', 'b', 'c') |
+-------------------------+------------------------+
| 1 | 1 |
+-------------------------+------------------------+
1 row in set (0.04 sec)
*/
select 12 is null, 23 = null, null = null, null <=>
null, null is null, 32 is not null;
/* 输出
+------------+-----------+-------------+---------------
+--------------+----------------+
| 12 is null | 23 = null | null = null | null <=> null |
null is null | 32 is not null |
+------------+-----------+-------------+---------------
+--------------+----------------+
| 0 | NULL | NULL | 1 |
1 | 1 |
+------------+-----------+-------------+---------------
+--------------+----------------+
1 row in set (0.00 sec)
*/
select 'HelloWorld' like 'hello%';
/* 输出
+----------------------------+
| 'HelloWorld' like 'hello%' |
+----------------------------+
| 1 |
+----------------------------+
1 row in set (0.00 sec)
*/
- 逻辑运算符