jointype : kw_join
                | kw_inner kw_join
                | outerjoin kw_outer kw_join
                | outerjoin kw_join

def p_jointype(self,t):
    """jointype : kw_join
                | kw_inner kw_join
                | outerjoin kw_outer kw_join
                | outerjoin kw_join
    """
    if len(t) <= 2 or t[1] == 'inner': t[0] = JoinTypeX(None, False, None)
    else: t[0] = JoinTypeX(t[1], True, None)