Home Database Mysql Tutorial MySQL搜索:WHERE

MySQL搜索:WHERE

Jun 07, 2016 pm 03:47 PM
mysql where designation search condition

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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