我可以一起使用COUNT（）和DISTINCT吗？

I would like to count the number of rows from a mysql table and not to include duplicate entries,

我想计算mysql表中的行数，而不是包含重复的条目，

Could I use distinct with count()?

我可以使用与count（）的distinct吗？

4 个解决方案

#1

Sure.

当然。

SELECT COUNT(DISTINCT column) FROM table;

#2

What you need is the following:

您需要的是以下内容：

SELECT field_type_name, count(*) FROM fields GROUP BY field_type_name;

This will give you something like this:

这会给你这样的东西：

image   14
string  75
text     9

#3

 SELECT COUNT(DISTINCT field) from Table

See this.

看到这个。

#4

SELECT count(DISTINCT column Name) as alias from table_Name;