Access 2.0 中的联合查询

Question

我正在尝试创建将在 Access 2.0 中运行的查询。

主表有两个标题栏和两个学分栏。一个人将出现在 Title A 或 Title B 中，并获得 A 或 B 的学分。只有 Title A 获得 Credit A 的学分，Title B 获得 Credit B 的学分

**Title A   Title B Credit A    Credit B**
James   Sam     1   0
Jason   James   1   1
Justin  Sara    1   1
Sam     James   1   0
Justin  Jason   1   1
Sara    James   1   0
Jason   Sam     0   1

我想要 Access 2.0 中的结果集，其中包含 A 和 B 总学分的人名

**Person    Credits**
Jason   2
James   2
Sam     2
Sara    2
Justin  2

在访问中执行此操作的最佳方法是什么？为 A 和 B 创建两个单独的查询并合并在一起并分组？

Click here for a better picture of the Table Description

Answer 1

你可以试试这个查询。

用SUM和titleA和titleB命名两个查询，然后使用UNION合并两个物种。你可以按人获得他们的总学分

SELECT Person,sum(totle) Credits
FROM 
(
    SELECT TitleA Person,SUM(CreditA) totle
    FROM T
    GROUP BY TitleA
    UNION ALL 
    SELECT TitleB Person,SUM(CreditB) totle
    FROM T
    GROUP BY TitleB
) t
GROUP BY Person

sqlfiddle:http://sqlfiddle.com/#!18/331f2/1

Answer 2

是的，你是对的！您使用 UNION ALL 组合所有人员和信用列，然后执行 GROUP BY。获取总和以总计信用列。

SELECT person, sum(credit) as credits
FROM 
  (
    SELECT TitleA as person,CreditA as credit
    FROM T
   UNION ALL 
   SELECT TitleB,CreditB
   FROM T
  ) t
GROUP BY Person

Answer 3

在 Access 2.0 中获取错误“FROM 子句中的语法错误”

SELECT FlightData.Person, FlightData.TailNumber, FlightData.Aircraft, Sum(FlightData.Landings) AS TotalLandings
FROM (
SELECT [Flight Data].Date, [Flight Data].Pilot AS Person, [Flight Data].[Aircraft Number] AS TailNumber, Aircraft.[Aircraft Type] AS Aircraft, [Flight Data].[Pilot Landings] AS Landings FROM [Flight Data] INNER JOIN Aircraft ON [Flight Data].[Aircraft Number] = Aircraft.[Tail Number]
UNION ALL
SELECT [Flight Data].Date, [Flight Data].CoPilot as Person,[Flight Data].[Aircraft Number] AS TailNumber, Aircraft.[Aircraft Type] as Aircraft, [Flight Data].[CoPilot Landings]AS Landings FROM [Flight Data]  INNER JOIN Aircraft ON [Flight Data].[Aircraft Number] = Aircraft.[Tail Number] 
)  AS FlightData
WHERE FlightData.[date] Between [Start Date] And [End Date]
GROUP BY FlightData.Person, FlightData.TailNumber, FlightData.Aircraft;