數據庫 Table1
Id
Table2Id
...
Table2
Id
StartTime
Duration //in hours
查詢 select * from Table1 join Table2 on Table2Id = Table2.Id
where starttime < :starttime and starttime + Dura
我有一個查詢: SELECT a.nick,grp,count(*) FROM help_mails^h JOIN佔一個ON h.helper = a.id WHERE關閉= 1 GROUP BY幫手,GRP,a.nick 是什麼此連接錯誤? 當我做了2個查詢: SELECT helper,grp,count(*) FROM help_mails h WHERE closed = 1 GROUP