如何在一列有多個條目的列上使用group by？

Question

我想在一列有很多條目的列上使用group by

表-A

Name price
AAA  12
BBB  13
AAA  0
CCC  24
AAA  0
DDD  0

現在我想找出Price為0 Name

但由於我有三次條目AAA ，我不能直接寫條件NOT Equal to 0簡單sql

請幫幫我，我想打印上面的表格_a應該是

只有D ，因為price為0 。

Answer 1

我假設價格不能低於零：

SELECT Name
FROM TableName
GROUP BY Name
HAVING SUM(price) = 0

或者只有一個價格的附加條件，即零

SELECT Name
FROM TableName
GROUP BY Name
HAVING COUNT(*) = 1 AND SUM(price) = 0

Answer 2

您可以通過使用聚合函數GROUP BY和HAVING子句來實現此目的：

SQLFiddle演示

SELECT name,SUM(price) as price
FROM table 
GROUP BY name
HAVING SUM(price) = 0

Answer 3

select name,max(price) as price from table group by name having max(price) =0

Answer 4

select name,max(price)
group by name
having max(price)=0