Question

我有两张桌子。

画; ID，艺术家，标题

runlog; VideoID，'加入视频.ID 日期时间

我想在视频表上运行查询，不包括三个条件的记录。（作为例子。我有多个条件，但如果我得到一些帮助，我可能会把其他一切都搞清楚。

过去一小时内在Runlog中显示的任何视频都不会显示在结果中
过去一小时内在动态广告中显示视频的任何艺术家将不会在查询中显示同一艺术家的任何其他记录
过去24小时内三次在runlog中显示视频的艺术家将不会在查询中显示相同艺术家的任何其他记录

这让我得到了第一个结果要求，但我觉得它写得更好。

    SELECT ID,Artist, Title FROM
    videos join runlog on runlog.videoID = videos.id
    where 
    (select COUNT(*) from runlog where datetime > DATEADD(hh,-12,GETDATE())
    and runlog.videoID = videos.id) = 0 
    order by Artist, Title

第二个要求我无法弄清楚如何将它们放在同一个查询中。

Answer 1

  SELECT ID, Artist, Title 
  FROM videos v join runlog l on l.videoID = v.id
  WHERE 
       -- 1. All in past hour will not show
       datetime < DATEADD(hour,-1,GETDATE())
       -- 2. 
       and not exists 
         ( select 1 
           from videos v2 join runlog l2 on l2.videoID = v2.id
           where v2.Artist = v1.Artist and datetime > DATEADD(hour,-1,GETDATE()) 
       ) 
       -- 3.
       and not exists 
         ( 
           select 1
           from
           (
              select count(1) recordCount
              from videos v3 join runlog l3 on l3.videoID = v3.id
              where v3.Artist = v1.Artist and datetime > DATEADD(hour,-24,GETDATE())
           )
           where recordCount>=3
       ) 
    order by Artist, Title

OR

  SELECT ID, Artist, Title 
      FROM videos v join runlog l on l.videoID = v.id
      WHERE 
           -- 1. All in past hour will not show
           datetime < DATEADD(hour,-1,GETDATE())
           and v1.Artist in 
        (
                    -- 2.
            select Artist
            from videos v2 join runlog l2 on l2.videoID = v2.id
            where datetime > DATEADD(hour,-1,GETDATE())
            union all
                    -- 3.
            select Artist
            from videos v3 join runlog l3 on l3.videoID = v3.id
            where datetime > DATEADD(hour,-24,GETDATE())
            group by v3.Artist having count(1) >= 3
        )

Answer 2

SELECT ID, Artist, Title
FROM Videos V
WHERE V.ARTIST NOT IN
(SELECT V2.Artist
       FROM RunLog R
       INNER JOIN Videos V2 ON V2.ID = R.VideosID
       WHERE dateTime >= DateAdd(hh, -1, GetDate())
 UNION ALL
 SELECT V3.Artist
       FROM RunLog R
       INNER JOIN Videos V3 ON V3.ID = R.VideosID
       WHERE dateTime >= DateAdd(hh, -24, GetDate())
       GROUP BY V3.Artist
       HAVING Count(*) >= 3  
     )
)

使用NOT EXISTS

也可以完成相同的查询

SELECT ID, Artist, Title
FROM Videos V
WHERE NOT EXISTS
(SELECT 1
       FROM RunLog R
       INNER JOIN Videos V2 ON V2.ID = R.VideosID
       WHERE dateTime >= DateAdd(hh, -1, GetDate())
         AND V2.Artist = V.Artist 
 UNION ALL
 SELECT 1
       FROM RunLog R
       INNER JOIN Videos V3 ON V3.ID = R.VideosID
       WHERE dateTime >= DateAdd(hh, -24, GetDate())
         AND V3.Artist = V.Artist
       GROUP BY V3.Artist
       HAVING Count(*) >= 3  
     )
)

条件2将自动满足条件1

Answer 3

此查询显式强制执行后两个约束，第一个隐式执行（强制第二个隐式强制执行第一个约束）。这是未经测试的，但它应该让你走上正确的轨道。

select ID, Artist, Title
from Video
where Artist not in (
  select V.Artist
  from Video V, Runlog R
  where V.ID = R.VideoID
    and R.datetime > dateadd(hour, -1, getdate())
  union
  select V.Artist
  from Video V, Runlog R
  where V.ID = R.VideoID
    and R.datetime > dateadd(hour, -24, getdate())
  group by V.Artist
  having count(*) > 2
);

根据表连接结果从查询中排除记录

3 个答案: