零基础带你学习MySQL—统计函数（合计函数）（十一）

阳光穿透心脏的1/2处 2022-10-11 00:48 169阅读 0赞

## 零基础带你学习MySQL—统计函数（合计函数）（十一） ##

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## count（\*）和count（列）的区别 ##

**count（\*）：返回满足条件的记录的行数**

**count（列）：统计满足条件的某列有多少个，但是会排除为空的情况**

**创建一张表**  
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