如何在MySQL中拆分列？
要拆分列，您需要在MySQL中使用SUBSTRING_INDEX()。让我们首先创建一个表-
create table DemoTable -> ( -> Name varchar(40) -> );
使用插入命令在表中插入一些记录-
insert into DemoTable values('John_Smith');
insert into DemoTable values('Carol_Taylor');
insert into DemoTable values('David_Miller');使用select语句显示表中的所有记录-
select *from DemoTable;
这将产生以下输出-
+--------------+ | Name | +--------------+ | John_Smith | | Carol_Taylor | | David_Miller | +--------------+ 3 rows in set (0.00 sec)
以下是在MySQL中拆分列的查询-
select if(locate('_',Name)=0,'',substring_index(Name, '_', 1)) from DemoTable;
这将产生以下输出：
+---------------------------------------------------------+
| if(locate('_',Name)=0,'',substring_index(Name, '_', 1)) |
+---------------------------------------------------------+
| John |
| Carol |
| David |
+---------------------------------------------------------+
3 rows in set (0.00 sec)