MySQL 中是否有 CONCAT() 的替代方案?
mysqlmysqli database
有，替代方案是 CONCAT_WS()。让我们首先创建一个表 −
mysql> create table DemoTable ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentName varchar(100) ); Query OK, 0 rows affected (0.74 sec)
示例
使用 insert 命令在表中插入一些记录 −
mysql> insert into DemoTable(StudentName) values('Chris');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable(StudentName) values('Robert');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable(StudentName) values('Bob');
Query OK, 1 row affected (0.12 sec)
使用 select 语句显示表中的所有记录 −
mysql> select *from DemoTable;
输出
+-----------+-------------+ | StudentId | StudentName | +-----------+-------------+ | 1 | Chris | | 2 | Robert | | 3 | Bob | +-----------+-------------+ 3 rows in set (0.00 sec)
让我们看看如何在 MySQL 中使用 CONCAT() 的替代方案 −
mysql> select concat_ws(SPACE(2), 'Student Name is:',StudentName) from DemoTable;
输出
+-----------------------------------------------------+ | concat_ws(SPACE(2), 'Student Name is:',StudentName) | +-----------------------------------------------------+ | Student Name is: Chris | | Student Name is: Robert | | Student Name is: Bob | +-----------------------------------------------------+ 3 rows in set (0.04 sec)
