获取行取决于列数和最大值

本文介绍了获取行取决于列数和最大值的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 限时删除！！ 我有3个表：文件，用户和回复 文件表 docid docName sendTo 1 休假 1 2 private 1 用户表 userid userName 1 john 2 结婚 回复表 replyid docid userid replyDate 1 1 1 14-06 -2015 2 1 2 15-60-2015 如何创建查询获取最后回复日期的回复计数 当我选择的时候文件= 1（john）的se senderid如下所示： docName numOfReplies lastReply vacation 2 15-06-2015 private 0 null 我该怎么做才能得到这个结果？ 编辑：AL）来自评论 这是我到目前为止所尝试的： SELECT distinct dbo.Documents.DocName， COUNT（ *） over （） AS [numOfReplies]， max（dbo.Replies，replyDate） as [lastreply] FROM dbo.Documents INNER JOIN dbo.Replies ON dbo.Documents.DocumentID = dbo.Replies.DocumentID INNER JOIN dbo.Users ON dbo.Documents.SendTo = dbo.Users.UserID WHERE dbo.Users.UserID = 1 GROUP BY dbo.Documents.DocumentID 解决方案 i have 3 tables : Documents, Users and RepliesDocuments tabledocid docName sendTo1 vacation 12 private 1Users tableuserid userName1 john2 marryReplies tablereplyid docid userid replyDate1 1 1 14-06-20152 1 2 15-60-2015how can i create query get the count of replies with last reply datewhen i choose senderid of document=1 (john) appear like this :docName numOfReplies lastReplyvacation 2 15-06-2015private 0 nullhow can i do that to get this result?EDIT: AL) from commentsThis is what I have tried so far:SELECT distinct dbo.Documents.DocName, COUNT(*) over () AS [numOfReplies], max(dbo.Replies,replyDate) as [lastreply]FROM dbo.Documents INNER JOIN dbo.Replies ON dbo.Documents.DocumentID = dbo.Replies.DocumentID INNER JOIN dbo.Users ON dbo.Documents.SendTo = dbo.Users.UserIDWHERE dbo.Users.UserID = 1GROUP BY dbo.Documents.DocumentID 解决方案 这篇关于获取行取决于列数和最大值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 1403页，肝出来的..