Sql id，其中列有两个条件

我有一张加入和离开公司的客户表

ID ActiveFrom ActiveTo

例如，我有一个where子句

where ActiveFrom <= '20170101' 
  and Activeto < '20170201'

我想把这样做的客户排除在离开公司但又回来的客户之外

所以我只想返回id 2

请帮助

您可以试试这个

SELECT * FROM Customer C1
WHERE C1.ActiveFrom <= '20170101' 
        AND C1.Activeto < '20170201'
        AND NOT EXISTS ( SELECT * FROM Customer C2
                WHERE C1.ID = C2.ID
                AND C2.ActiveTo IS NULL )

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可以对WHERE语句使用子查询：

SELECT *
FROM tablename
WHERE (SELECT id FROM tablename WHERE activeTo is null) <> id
GROUP By id

您可以在此处找到更多信息：

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这是brill谢谢，最棒的是将C2.ActiveTo为空更改为C2.ActiveFrom>='20170101'，这是fab谢谢

SELECT *
FROM tablename
WHERE (SELECT id FROM tablename WHERE activeTo is null) <> id
GROUP By id