1

我有这个 sql 查询： 

SELECT Customer.IDCustomer, Customer.Name,
Sign.IdSign, Sign.Name, Sign.Delete
FROM Customer
LEFT JOIN  Sign_Customer ON Sign_Customer.IDCustomer=Customer.IDCustomer 
     AND  ( SELECT CAST(CASE WHEN S_C.Delete=0 OR S_C.Delete is Null THEN 1 ELSE 0 END AS BIT )
            FROM Sign AS S_C
            WHERE S_C.IdSign=Sign_Customer.IdSign)=1
LEFT JOIN Sign ON Sign.IdSign=Sign_Customer.IdSign

ORDER BY Customer.Name

此查询工作正常，但我想知道它是否存在另一种方法来过滤我的第一个左连接而不使用 SELECT CAST... 条件。

更新

抱歉，我没有解释我想要的结果：

  • 我所有的客户都没有签名
  • 我所有启用签名的客户

如果不存在启用标志，则禁用标志的客户不会出现或显示为“无标志”。

示例：我的客户表

IDCustomer   | Name
1            | Customer 1
2            | Customer 2
3            | Customer 3
4            | Customer 4

签收客户：

IDCustomer   | IdSign
1            | 1
3            | 2
3            | 3
3            | 5
4            | 4

符号

IdSign       | Name         | Delete
1            | Sign1        | 0
2            | Sign2        | 1
3            | Sign3        | 0
4            | Sign4        | 1
5            | Sign5        | 0

结果

Customer.IDCustomer | Customer.Name  | Sign.IdSign | Sign.Name | Sign.Delete
1                   | Customer 1     | 1           | Sign1     | 0
2                   | Customer 2     | null        | null      | null
3                   | Customer 3     | 3           | Sign3     | 0
3                   | Customer 3     | 5           | Sign5     | 0
4                   | Customer 4     | null        | null      | null
4

3 回答 3

0

下面的呢？

   SELECT Customer.IDCustomer
        , Customer.Name
        , Sign.IdSign
        , Sign.Name
        , Sign.Delete
     FROM Customer
LEFT JOIN Sign_Customer
     JOIN Sign
       ON Sign_Customer.IdSign = Sign.IdSign
      AND Sign.Delete = 0
       ON Customer.IDCustomer = Sign_Customer.IDCustomer
 ORDER BY Customer.NAME;
于 2013-04-13T23:13:09.470 回答
0 
SELECT Customer.IDCustomer, Customer.Name, Sign.IdSign, Sign.LibEnseigne, Sign.Delete
FROM Customer
LEFT JOIN  Sign_Customer ON Sign_Customer.IDCustomer=Customer.IDCustomer 
LEFT JOIN Sign ON Sign.IdSign=Sign_Customer.IdSign
AND (S_C.Delete=0 OR S_C.Delete is Null)
ORDER BY TEnseigne.NomEnseigne, Customer.Name
于 2013-04-12T09:24:44.603 回答
0

我相信这符合您的标准：

SELECT Customer.IDCustomer, Customer.Name,
Sign.IdSign, Sign.Name, Sign.Delete
FROM Customer
LEFT JOIN (
  select Sign_Customer.*
  from Sign_Customer
  join Sign on S_C.IdSign=Sign_Customer.IdSign
  where isnull(S_C.Delete,0) = 0
) Sign_Customer ON Sign_Customer.IDCustomer=Customer.IDCustomer 
LEFT JOIN Sign ON Sign.IdSign=Sign_Customer.IdSign    
ORDER BY Customer.Name
于 2013-04-14T03:33:10.067 回答