如何添加重复的varchar值而不在MySQL中显示错误？
为此，让我们看一个例子，首先创建一个-
mysql> create table DemoTable1409 -> ( -> FirstName varchar(20), -> UNIQUE KEY UN_FirstName(FirstName) -> );
以下是添加重复的varchar的查询-
mysql> alter table DemoTable1409 drop index UN_FirstName; Records: 0 Duplicates: 0 Warnings: 0
使用insert在表中插入一些记录-
mysql> insert into DemoTable1409 values('Chris');
mysql> insert into DemoTable1409 values('Chris');
mysql> insert into DemoTable1409 values('David');使用选择显示表中的所有记录-
mysql> select * from DemoTable1409;
这将产生以下输出-
+-----------+ | FirstName | +-----------+ | Chris | | Chris | | David | +-----------+ 3 rows in set (0.00 sec)