MySQL搜索:WHERE
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:
a 查找价格等于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
c 检索价格小于10的所有产品:
d 检索值的范围
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!
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。

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