$result = Db::connect('hrdb')
->table('Kq_source')
->field(['Kq_source.FDateTime', 'Kq_source.MachNo', 'Kq_Mach.Note'])
->join('Kq_Mach', 'Kq_source.MachNo = Kq_Mach.MachNo')
->join('ZlEmployee', 'Kq_source.EmpID = ZlEmployee.ID')
->where('ZlEmployee.Code', '=', $code)
->where('Kq_source.FDateTime', '>=', $start .' 0:0:0')
->where('Kq_source.FDateTime', '<=', $end . ' 23:59:59')
->order('Kq_source.FDateTime')
->select();

出错提示“SQLSTATE[42000]: [Microsoft][ODBC Driver 11 for SQL Server][SQL Server]无法绑定由多个部分组成的标识符 "Kq_source.FDateTime"。”
是什么原因