我正在尝试在Access中创建一系列查询,以计算77个县中每个县的每个种族的客户数量。
这是我的一个查询的SQL代码,我正在尝试为此...
SELECT [ClientsByCounty-Asian].County, [ClientsByCounty-Asian].CountyName, Count([ClientsByCounty-Asian].Asian) AS CountOfAsian
FROM [ClientsByCounty-Asian]
GROUP BY [ClientsByCounty-Asian].County, [ClientsByCounty-Asian].CountyName;
此查询仅返回77个县中的16个。我需要它显示所有77个县,即使结果为零并且没有记录。
如何让它显示其他61个县?
答案 0 :(得分:8)
假设您的77
个县存储在名为Counties
的表格中<:p>
SELECT c.CountyName, COUNT([ClientsByCounty-Asian].County)
FROM Counties c
LEFT JOIN
[ClientsByCounty-Asian]
ON [ClientsByCounty-Asian].County = c.County
GROUP BY
c.County, c.CountyName