MySQL创建计算字段――MySQL系列（五）

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MySQL创建计算字段――MySQL系列（五）_MySQL

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Jun 01, 2016 pm 01:17 PM

Splicingdatabase

1、字段

字段与列含义差不多，数据库列一般叫列，字段一般是指计算字段

2、拼接字段

拼接——将值连接到一起构成单个值

Concat()函数

SELECT Concat(name,&#39;(&#39;,country,&#39;)&#39;)AS title FROM companyOrder BY name;

这里的AS title,是取别名，title就是计算字段

3、执行算数计算

可以进行加减乘除的运算

Select prod_num*prod_price，prod_nameFROM products

4、如何测试计算

SELECT 3*2，将返回6

SELECT NOW(),将返回现在时间

Statement

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