Okay, so why does wrapping the order by in a function fix it? (or not doing a join, or doing an implicit join)
Cody Cutrer On Wed, May 22, 2013 at 11:36 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Cody Cutrer <c...@instructure.com> writes: > > create table test1 (id integer, sortable_name varchar); > > create table test2 (id integer, test1_id integer); > > select test1.sortable_name, sortable_name from test1 inner join test2 > > on test1.id=test1_id order by sortable_name; > > ERROR: ORDER BY "sortable_name" is ambiguous > > LINE 1: ...t1 inner join test2 on test1.id=test1_id order by > sortable_n... > > I think it's unhappy because "sortable_name" could refer to either of > the output columns (under the old SQL92 convention that an ORDER BY item > is an output column name). Probably the easiest way to dodge that is to > qualify the name, ie ORDER BY test1.sortable_name. A different line of > attack is to use AS to relabel whichever output column you don't want to > match. > > regards, tom lane >
