以下是我的表格:
1. tbluser
UserNumber - PK
Name
MemberType - Number
StationNumber - FK (connected to StationNo of tblStation)
2.tblStation
StationNo - PK
StationName
3.tblUserLogs
LogID - PK
UserID - FK (connected from UserNumber of tblusers)
LastLog
我想要做的就是显示名称(tblusers),StationName(tblStation)和LastLog(tblUserLogs),其中MemberType不等于1.
这是我的尝试...
SELECT tblusers.FirstName, tblstation.StationName, tblUserLogs.LastLog
FROM (tblstation INNER JOIN tblusers ON tblstation.StationNo = tblusers.StationNumber)
INNER JOIN tblUserLogs ON tblusers.UserNumber = tblUserLogs.UserID
WHERE (((tblusers.MemberType)<>1))
但是,我会重复记录我的用户。它显示所有LastLog数据,而不是显示最新数据。
我该怎么做?
答案 0 :(得分:1)
使用此查询:
SELECT tblusers.FirstName, tblstation.StationName, MAX(tblUserLogs.LastLog)
FROM (tblusers LEFT JOIN tblstation ON tblstation.StationNo = tblusers.StationNumber)
LEFT JOIN tblUserLogs ON tblusers.UserNumber = tblUserLogs.UserID
WHERE tblusers.MemberType != 1