在结果表中显示MySQL用户定义的变量值？
使用@表示变量，使用concat_ws()在表中显示并置结果。让我们首先创建一个表-
mysql> create table DemoTable1508 -> ( -> StudentFirstName varchar(20), -> StudentLastName varchar(20) -> );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable1508 values('Chris','Brown');
mysql> insert into DemoTable1508 values('David','Miller');
mysql> insert into DemoTable1508 values('John','Doe');使用select语句显示表中的所有记录-
mysql> select * from DemoTable1508;
这将产生以下输出-
+------------------+-----------------+ | StudentFirstName | StudentLastName | +------------------+-----------------+ | Chris | Brown | | David | Miller | | John | Doe | +------------------+-----------------+ 3 rows in set (0.00 sec)
这是在结果表中显示MySQL变量的查询-
mysql> select @FullName:=concat_ws('-',StudentFirstName,StudentLastName) from DemoTable1508;这将产生以下输出-
+------------------------------------------------------------+
| @FullName:=concat_ws('-',StudentFirstName,StudentLastName) |
+------------------------------------------------------------+
| Chris-Brown |
| David-Miller |
| John-Doe |
+------------------------------------------------------------+
3 rows in set (0.03 sec)