用MySQL连接一个新列中的所有列
让我们首先创建一个-
mysql> create table DemoTable1396 -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Name varchar(40), -> Age int -> );
使用insert在表中插入一些记录-
mysql> insert into DemoTable1396(Name,Age) values('Chris',21);
mysql> insert into DemoTable1396(Name,Age) values('David',24);
mysql> insert into DemoTable1396(Name,Age) values('Bob',26);使用选择显示表中的所有记录-
mysql> select * from DemoTable1396;
这将产生以下输出-
+----+-------+------+ | Id | Name | Age | +----+-------+------+ | 1 | Chris | 21 | | 2 | David | 24 | | 3 | Bob | 26 | +----+-------+------+ 3 rows in set (0.00 sec)
以下是将列连接到单个新列中的查询-
mysql> select Id,Name,Age, concat(Id,Name,Age) as AllColumns from DemoTable1396;
这将产生以下输出-
+----+-------+------+------------+ | Id | Name | Age | AllColumns | +----+-------+------+------------+ | 1 | Chris | 21 | 1Chris21 | | 2 | David | 24 | 2David24 | | 3 | Bob | 26 | 3Bob26 | +----+-------+------+------------+ 3 rows in set (0.00 sec)