Sql server tsql 2012隐式连接8个表

我试图了解以下带有隐式联接的t-sql 2012当前是如何在生产环境中执行的：

SELECT  distinct Cyear
FROM     dbo.Individual INNER JOIN
              dbo.Course INNER JOIN
              dbo.CalendarYear ON dbo.Course.CalendarYearID = dbo.CalendarYear.CalendarYearID
      AND CalendarYear.endYear >= (SELECT DISTINCT A.endYear FROM CalendarYear A WHERE
              A.active = 1)
      INNER JOIN
              dbo.Cust ON dbo.CalendarYear.CustID = dbo.Cust.CustID INNER JOIN
              dbo.BridgeCust ON dbo.Course.CourseID = dbo.BridgeCust.CourseID ON 
              dbo.Individual.StudID = dbo.BridgeCust.StudID INNER JOIN
              dbo.User INNER JOIN
              dbo.BridgeUser ON dbo.User.UserID = dbo.BridgeUser.UserID
              ON dbo.BridgeCust.CourseID = dbo.BridgeUser.CourseID

dbo.Individual与dbo.Course表没有直接连接。第一次使用dbo.Individual 正在与BridgeCust表联接。bridgeCust表仅为该表的 表加上dbo.Individual和dbo.Course表的键

因此，您能解释一下隐式连接是如何设置的吗

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您可以编写sql来向我展示sql是如何被设置为真正显式执行的吗？

这可能就是正在发生的事情

SELECT  DISTINCT Cyear
FROM dbo.Individual
INNER JOIN dbo.Course
        INNER JOIN dbo.CalendarYear
            ON dbo.Course.CalendarYearID = dbo.CalendarYear.CalendarYearID
           AND CalendarYear.endYear >= (
                                        SELECT DISTINCT
                                               A.endYear
                                        FROM CalendarYear AS A
                                        WHERE A.active = 1)
        INNER JOIN dbo.Cust
            ON dbo.CalendarYear.CustID = dbo.Cust.CustID
        INNER JOIN dbo.BridgeCust
            ON dbo.Course.CourseID = dbo.BridgeCust.CourseID
ON dbo.Individual.StudID = dbo.BridgeCust.StudID
INNER JOIN dbo.[User]
        INNER JOIN dbo.BridgeUser
            ON dbo.[User].UserID = dbo.BridgeUser.UserID
ON dbo.BridgeCust.CourseID = dbo.BridgeUser.CourseID;

或者重写如下，它可能会更清楚

SELECT  DISTINCT Cyear
FROM dbo.Individual
INNER JOIN (SELECT dbo.BridgeCust.StudID,dbo.BridgeCust.CourseID FROM dbo.Course
        INNER JOIN dbo.CalendarYear
            ON dbo.Course.CalendarYearID = dbo.CalendarYear.CalendarYearID
           AND CalendarYear.endYear >= (
                                        SELECT DISTINCT A.endYear
                                        FROM CalendarYear AS A
                                        WHERE A.active = 1)
        INNER JOIN dbo.Cust
            ON dbo.CalendarYear.CustID = dbo.Cust.CustID
        INNER JOIN dbo.BridgeCust
            ON dbo.Course.CourseID = dbo.BridgeCust.CourseID) F1
ON dbo.Individual.StudID = F1.StudID
INNER JOIN (SELECT dbo.BridgeUser.UserID, dbo.BridgeUser.CourseID FROM dbo.[User]
        INNER JOIN dbo.BridgeUser
            ON dbo.[User].UserID = dbo.BridgeUser.UserID) F2
ON F2.CourseID = F1.CourseID;

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在这些表之间是否定义了外键？是否实际运行？我很确定，如果没有后续的

ON

，就不能使用

内部联接。对我来说，这似乎是不正确的语法。是的，这会运行。我认为执行计划改变了连接顺序。因此，我相信问题已经解决了。