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逻辑运算符:
MySQL支持的逻辑运算符如下：
AND(&&)运算符:
逻辑AND(&&)运算符说明是否两个运算域是真的。让我们参见以下的使用AND运算符的语句。
mysql> select studid, name from student where marks > 80
and marks < 100;
(or)
mysql> select studid, name from student where marks > 80
&& marks < 100;
+--------+-------+
| studid | name |
+--------+-------+
| 4 | jack |
| 8 | mille |
+--------+-------+
2 rows in set (0.00 sec)
在以上的示例中，列出了在80-100之间的学生名字和studid。
OR(||)运算符:
逻辑OR(||)运算符说明是否单个的运算域是真的。 让我们参见以下的使用OR运算符的语句。
mysql> select name, marks, address from student where
name like 'a%' or name like 's%';
(or)
mysql> select name, marks, address from student where
name like 'a%' || name like 's%';
+-------+-------+------------------+
| name | marks | address |
+-------+-------+------------------+
| steve | 100 | 5th cross street |
| anne | 100 | downing street |
| steve | 75 | downing street |
| anne | 80 | edinburgh |
+-------+-------+------------------+
4 rows in set (0.00 sec)
在以上的示例语句中，列出了学生名字字母在A和S之间的学生的名字、分数和地址。
NOT(!)运算符:
逻辑NOT(!)运算符只有一个域，它用于返回相反的值。
mysql> select * from student where not (studid=1);
(or)
mysql> select * from student where ! (studid=1);
+--------+-------+-------+-----------------+---------+
| studid | name | marks | address | phone |
+--------+-------+-------+-----------------+---------+
| 2 | david | 100 | welling street | 547896 |
| 4 | jack | 82 | welling street | 2436821 |
| 5 | anne | 100 | downing street | 2634821 |
| 6 | steve | 75 | downing street | 2874698 |
| 7 | anne | 80 | edinburgh | 2569843 |
| 8 | mille | 98 | victoria street | 1236547 |
+--------+-------+-------+-----------------+---------+
6 rows in set (0.00 sec)
它将列出所有学生的细节，除了studid 1。
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