Question

我们的数据库中有一系列预订，每个预订都有一个多个会话序列。每个会话都有一个“停止”，其中包含一个DateTime。

我想选择所有会话在两个日期之间结束的预订。

SELECT DISTINCT b.*
  FROM Booking as b
    JOIN Sequence as se
    JOIN Session as s
ON (b.sequence_id=se.id AND s.sequence_id=se.id
    AND s.stop between '2012-09-01 00:00:00' AND '2012-12-01 00:00:00');

此SQL选择包含一个或多个已结束会话的预订。

我只想要所有会话结束的预订。

有什么想法吗？

Answer 1

thanx，确切的查询是这样的：

SELECT b.id, s.stop  
  FROM Booking as b  
  JOIN Sequence as se  
  JOIN Session as s  
     ON (b.sequence_id=se.id AND s.sequence_id=se.id)  
        where not exists (SELECT ss.id from Session as ss where ss.sequence_id=se.id and ss.stop < '2012-09-01 00:00:00')  
        and not exists (SELECT ss.id from Session as ss where ss.sequence_id=se.id and ss.stop > '2012-12-01 00:00:00');

Answer 2

我想知道你是否可以这样做：

SELECT DISTINCT b.*  
  FROM Booking as b  
  JOIN Sequence as se  
  JOIN Session as s  
     ON (b.sequence_id=se.id AND s.sequence_id=se.id )  
  where s.stop between '2012-09-01 00:00:00' AND '2012-12-01 00:00:00')  
     and not exists ( s.stop < '2012-09-01 00:00:00' )  
     and not exists ( s.stop > '2012-12-01 00:00:00');

虽然语法不太正确。

选择所有已结束的预订

2 个答案: