Sql语句错误：INNER JOIN＆amp;未知栏目

Question

我无法弄清楚，为什么这句话不会运行......

SELECT T1.* , T2.* , T3 . * , T4 . * , T5.Sessionname, T5.Session_ID, T5.Lernsession, T5.Session_Beschreibung, T5.User_ID, T6.Username, T6.ID, T7.*
FROM Session_Fragen T1, Sessions T5


INNER JOIN Fragen T4 ON T1.Frage_ID = T4.Frage_ID
INNER JOIN Semester T2 ON T2.Semester_ID = T4.Semester_ID
INNER JOIN Faecher T3 ON T3.Fach_ID = T4.Fach_ID
INNER JOIN Userdaten T6 ON T5.User_ID = T6.ID
LEFT JOIN Medien T7 ON  T7.Frage_ID = T1.Frage_ID

WHERE 
T1.Session_ID =1655
AND T1.User_ID =2
AND T5.Session_ID =1655
AND T4.Meldung =0
AND T4.Freigabe =1
AND T5.User_ID =2

ORDER BY T4.Fach_ID

我正在尝试解决错误：＃1054 - 'on子句'中的未知列'T1.Frage_ID' 几个小时的夫妇没有任何成功...

任何人都可以看到我做错了吗？