GROUP BY

SELECT "栏位1", SUM("栏位2") FROM "表格名" GROUP BY "栏位1"

在我们的示范上，

Store_Information 表格

store_name	Sales	Date
Los Angeles	$1500	Jan-05-1999
San Diego	$250	Jan-07-1999
Los Angeles	$300	Jan-08-1999
Boston	$700	Jan-08-1999

我们就打入，

SELECT store_name, SUM(Sales)
FROM Store_Information
GROUP BY store_name

结果:

store_name	SUM(Sales)
Los Angeles	$1800
San Diego	$250
Boston	$700