SELECT A.*,IFNULL(B.GuestName,'') AS GuestName,IFNULL(C.ClassName,'') AS ClassName,IFNULL(D.CourseName,'') AS CourseName,IFNULL(E.RoomName,'') AS RoomName,IFNULL(F.TeacherName,'') AS TeacherName
SELECT A.*,IFNULL(B.GuestName,'') AS GuestName,IFNULL(B.GuestState,0) AS GuestState,IFNULL(C.ClassName,'') AS ClassName
,IFNULL(D.CourseName,'') AS CourseName,IFNULL(E.RoomName,'') AS RoomName,IFNULL(F.TeacherName,'') AS TeacherName
FROM RB_Class_Check AS A LEFT JOIN rb_order_guest AS B ON A.OrderGuestId=B.Id