sqllite错误“不支持加入”

Question

我有以下查询

 List<FullSthotram> sthotraas = (from m in db.Table<MSthotram>()
                                                   join q in db.Table<MUserSthotram>() on m.SthotraID equals q.SthotramID into mq
                                                   from r in mq.DefaultIfEmpty(new MUserSthotram())
                                                   join n in db.Table<MLanguage>() on m.LanguageID equals n.LanguageID
                                                   join o in db.Table<MAuthor>() on m.AuthorID equals o.AuthorID
                                                   join p in db.Table<MGod>() on m.GodID equals p.GodID
                                                   where m.IsActive == true && (m.SthotraID == SthotramID)
                                                   select new FullSthotram()
                                                   {
                                                       Author = o.Name,
                                                       God = p.Name,
                                                       Name = m.Name,
                                                       Language = n.Name,
                                                       SthotraID = m.SthotraID,
                                                       SthotramData = m.SthotramData,
                                                       NativeName = m.NativeName
                                                   }).ToList();

很好地检索数据

 List<FullSthotram> sthotraas = (from m in db.Table<MSthotram>()
                                                   join n in db.Table<MLanguage>() on m.LanguageID equals n.LanguageID
                                                   join o in db.Table<MAuthor>() on m.AuthorID equals o.AuthorID
                                                   join p in db.Table<MGod>() on m.GodID equals p.GodID
                                                   where m.IsActive == true && (m.SthotraID == SthotramID)
                                                   select new FullSthotram()
                                                   {
                                                       Author = o.Name,
                                                       God = p.Name,
                                                       Name = m.Name,
                                                       Language = n.Name,
                                                       SthotraID = m.SthotraID,
                                                       SthotramData = m.SthotramData,
                                                       NativeName = m.NativeName
                                                   }).ToList();

返回错误，表示不支持连接

除了左边的连接外，不确定两个查询之间有什么不同。请帮我找出问题所在。提前致谢