MS SQL中的嵌套连接，无法正常工作

Question

这是表结构（相关位）：

我正在尝试找到与clientID上的声明和声明日期匹配的contactLog条目（实际上在8小时内）。这就是我想出的：

SELECT
D.ClientID
D.DeclarationID   
CL.ContactDescription,
CL.ContactDate,

FROM Declarations D

INNER JOIN  (Contacts C
         INNER JOIN (PartialContacts PC
             INNER JOIN ContactLogs CL
                ON PC.ContactPartID = CL.ContactPartID )
            on PC.ContactID = C.ContactID
     )  
    ON C.ClientID = D.ClientID AND DATEDIFF(hour, D.DeclarationDate, CL.ContactDate) < 8

但是，连接功能不正常，因为我为CL.ContactDate返回了不匹配的日期，并且很明显它只返回CL中该患者ID的每一行。我想......我不确定会出现什么问题。

Answer 1

感谢Damien：

我没有指定datediff的下限，因此匹配无法正常工作。显然，连接很好：

SELECT
D.ClientID
D.DeclarationID   
CL.ContactDescription,
CL.ContactDate,

FROM Declarations D

INNER JOIN  (Contacts C
         INNER JOIN (PartialContacts PC
             INNER JOIN ContactLogs CL
                ON PC.ContactPartID = CL.ContactPartID )
            on PC.ContactID = C.ContactID
     )  
    ON C.ClientID = D.ClientID AND DATEDIFF(hour, D.DeclarationDate, CL.ContactDate) < 8 DATEDIFF(hour, D.DeclarationDate, CL.ContactDate) > 0.1

Answer 2

SELECT
D.ClientID
D.DeclarationID   
CL.ContactDescription,
CL.ContactDate
FROM Declarations D
INNER JOIN Clients CL ON D.ClientID=CL.ClientID
INNER JOIN  Contacts CO ON CL.ClientID=CO.ClientID
INNER JOIN PartialContact PC ON PC.ContactID=CO.ContactID
INNER JOIN ContactLog CL ON CL.ContactPartID=PC.ContactPartID
WHERE DATEDIFF(hour, D.DeclarationDate, CL.ContactDate) BETWEEN 0 AND 8