在使用MySQL SELECT语句时，给每个值添加一个百分比（%）符号

要添加百分号符号，请使用CONCAT()函数。让我们先创建一个表格 −

mysql> create table DemoTable
(
    StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,
    StudentName varchar(100),
    StudentScore int
);
Query OK, 0 rows affected (0.68 sec)

使用插入命令向表格中插入一些记录 −

mysql> insert into DemoTable(StudentName,StudentScore) values('John',65);
Query OK, 1 row affected (0.09 sec)
mysql> insert into DemoTable(StudentName,StudentScore) values('Chris',98);
Query OK, 1 row affected (0.30 sec)
mysql> insert into DemoTable(StudentName,StudentScore) values('Robert',91);
Query OK, 1 row affected (0.09 sec)

使用select语句显示表格中的所有记录 −

mysql> select *from DemoTable;

这将产生以下输出 −

+-----------+-------------+--------------+
| StudentId | StudentName | StudentScore |
+-----------+-------------+--------------+
|          1 | John        | 65           |
|          2 | Chris       | 98           |
|          3 | Robert      | 91           |
+-----------+-------------+--------------+
3 rows in set (0.00 sec)

以下是在使用MySQL SELECT语句时将百分比（%）符号添加到每个值末尾的查询 −

mysql> select StudentId,StudentName,concat(StudentScore,'%') AS StudentScore from DemoTable;

这将产生以下输出 −

+-----------+-------------+--------------+
| StudentId | StudentName | StudentScore |
+-----------+-------------+--------------+
|          1 | John        | 65%          |
|          2 | Chris       | 98%          |
|          3 | Robert      | 91%          |
+-----------+-------------+--------------+
3 rows in set (0.00 sec)