SQL查询获得列总数

Question

什么是SQL查询获得最后一行？

Region Country  City Population 

Africa Ghana   Accra 11200 
Africa Ghana   Nzma 1186 
Africa Ghana   Bole 160 
Africa Ghana   3  12546 

Answer 1

SELECT Table.Region, Table.Country, Sum(Table.[Population]) AS [Sum Population] 
FROM Table 
GROUP BY Table.Region, Table.Country; 

“表是

Answer 2

使用TSQL，你可以尝试：

SELECT Region, Country, COUNT(City), SUM(Population) FROM TableName 
GROUP BY Region, Country