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這次給大家帶來sql的聚合聚合與排序，使用SQL聚合函數與排序的聚合有哪些，下面就是實戰案例，一起來看一下。

語法：

select count(*)|count(列名) from table_name [where where_defination];Select count(id) from stu;Select count(name) from stu where math > 90;select count (name) from stu where chines+math+English> 250;

sum函數

Select sum (列名) from stu [where where_defination];  Select sum (列名),sum(列名), sum(列名) from stu [where where_definition];  Select sum (列名)+sum(列名)+ sum(列名) from stu [where where_definition];  Select sum (列名)+sum(列名)+sum(列名) as 總分 from stu [where where_definition];  Select sum (列名)/count(name) from stu [where where_defination];  Select avg(math) from stu;  Select avg(math + chines + english) from stu;  Select max|min(列名) from stu;  Select max(math + chines + english) from stu;  Select min(math + chines + english) from stu;

對聚合結果排序

使用聚合er by 子句排序查詢結果

Select column1, column2, column3 from table order by column asc|desc

order by指排序的列，也可以是select后面指定的列名

order by 子句應位于select 語句的結尾

Select name, math from stu order by math;  select name, math+english+chines from stu order by math+english+chines desc;  select name, math+english+chines from stu where name like 'zhang%' order by math+english+chines desc;

SQL的聚合函數與排序

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