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MySQL搜索：WHERE

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Jun 07, 2016 pm 03:47 PM

mysqlwheredesignationsearchcondition

MySQL指定搜索条件进行搜索可以使用where条件。在SELECT语句中，数据根据WHERE子语句中指定的条件进行过滤，WHERE子语句在表名之后给出。 product表如下： a 查找价等于2.50的行对于WHERE语句后面的操作符有如下种类，有了这些操作符就可以进行相应的条件

MySQL指定搜索条件进行搜索可以使用where条件。

在SELECT语句中，数据根据WHERE子语句中指定的条件进行过滤，WHERE子语句在表名之后给出。

product表如下：

MySQL搜索：WHERE

a 查找价格等于2.50的行

MySQL搜索：WHERE

对于WHERE语句后面的操作符有如下种类，有了这些操作符就可以进行相应的条件过滤了：

操作符	说明
=	等于
	不等于
！=	不等于
	小于
	小于等于
>	大于
>=	大于等于
BETWEEN	指定两个值之间

b 字符检索

MySQL搜索：WHERE

c 检索价格小于10的所有产品：

MySQL搜索：WHERE

d 检索值的范围

MySQL搜索：WHERE

本想在检索后的结果中排序显示，但是这样做好像不行，可能是SELECT后只可以接一个子句：//犯了明显的一个错误 W H E R E 拼写错误，多些xianxueniaoli13的指正！

MySQL搜索：WHERE

条件过滤后，可以以order关键字再进行排序，由此可见数据库功能之强大。

MySQL搜索：WHERE

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