在同一个 MySQL 查询中使用 NOT IN、OR 和 IS NULL 显示过滤后的记录
mysqlmysqli database更新于 2023/10/16 5:23:00
首先我们创建一个表 −
mysql> create table DemoTable793( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentName varchar(100) ); Query OK, 0 rows affected (0.81 sec)
使用 insert 命令在表中插入一些记录 −
mysql> insert into DemoTable793(StudentName) values('Adam');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable793(StudentName) values('Bob');
Query OK, 1 row affected (0.16 sec)
mysql> insert into DemoTable793(StudentName) values(null);
Query OK, 1 row affected (0.16 sec)
mysql> insert into DemoTable793(StudentName) values('Chris');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable793(StudentName) values('Robert');
Query OK, 1 row affected (1.03 sec)
使用 select 语句显示表中的所有记录 −
mysql> select *from DemoTable793;
这将产生以下输出 −
+-----------+-------------+ | StudentId | StudentName | +-----------+-------------+ | 1 | Adam | | 2 | Bob | | 3 | NULL | | 4 | Chris | | 5 | Robert | +-----------+-------------+ 5 rows in set (0.00 sec)
以下是在同一个 MySQL 查询中使用 NOT IN、OR 和 IS NULL 的查询 −
mysql> select *from DemoTable793 where StudentName NOT IN('Chris') OR StudentName IS NULL;
这将产生以下输出 −
+-----------+-------------+ | StudentId | StudentName | +-----------+-------------+ | 1 | Adam | | 2 | Bob | | 3 | NULL | | 5 | Robert | +-----------+-------------+ 4 rows in set (0.00 sec)
