mysql select语句中使用函数

实例如下：

创建数据表：

<code class="language-sql">mysql> CREATE TABLE Employee(
    ->     id            int,
    ->     first_name    VARCHAR(15),
    ->     last_name     VARCHAR(15)
    -> );
Query OK, 0 rows affected (0.03 sec)</code>

 

向表中插入数据：

<code class="language-sql">mysql> insert into Employee(id,first_name, last_name)values (1,'Jason','Martin');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name)values(2,'Alison','Mathews');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name)values(3,'James','Smith');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name)values(4,'Celia','Rice');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name)values(5,'Robert','Black');
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name)values(6,'Linda', 'Green');
Query OK, 1 row affected (0.01 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name)values(7,'David','Larry');
Query OK, 1 row affected (0.02 sec)

mysql>
mysql> insert into Employee(id,first_name, last_name)values(8,'James','Cat');
Query OK, 1 row affected (0.00 sec)</code>

select语句中使用函数

<code class="language-sql">mysql> SELECT concat(First_Name, " ",Last_Name) AS Name FROM Employee;
+----------------+
| Name           |
+----------------+
| Jason Martin   |
| Alison Mathews |
| James Smith    |
| Celia Rice     |
| Robert Black   |
| Linda Green    |
| David Larry    |
| James Cat      |
+----------------+
8 rows in set (0.00 sec)</code>