a way to cancel available query.order_by

query has no official way to cancel an order_by. query.order_by(whatever) only adds to existing order list, it never removes. this is any version 0.3/0.4/0.5 - the possible q=q.order_by() and q=q.order_by(None) do nothing

here a patch to make q.order_by(None) cancel any previous order_by, so q.order_by(a).order_by(None).order_by(b) orders by b and not by a,b

here a test case:

from sqlalchemy import * from sqlalchemy.orm import * m = MetaData('sqlite:///') m.bind.echo=True t = Table( 't', m, Column('a', Integer), Column('b', Integer, primary_key=True) ) class T(object): pass mapper( T,t) m.create_all() s = create_session() q = s.query(T).order_by( T.a).order_by( None).order_by( T.b) print q.all()

the result query is: SELECT t.a AS t_a, t.b AS t_b FROM t ORDER BY t.a, t.b

adding something like this at beginning of Query.order_by() would fix it: if not criterion: self._order_by = False return

the result query is what expected: SELECT t.a AS t_a, t.b AS t_b FROM t ORDER BY t.b

az()svilendobrev_com

patches attached

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