From: pgsql-general-ow...@postgresql.org [mailto:pgsql-general-ow...@postgresql.org] On Behalf Of Gauthier, Dave Sent: Tuesday, October 23, 2012 3:31 PM To: pgsql-general@postgresql.org Subject: Re: [GENERAL] Need sql to pull data from terribly architected table
Thanks for the answers. But I also have a predicate... select col1,col2 from foo where col4='c4' and col5 <> 'xxx'; How is that done? From: Richard Broersma [mailto:richard.broer...@gmail.com] Sent: Tuesday, October 23, 2012 3:24 PM To: ch...@chriscurvey.com Cc: Gauthier, Dave; pgsql-general@postgresql.org Subject: Re: [GENERAL] Need sql to pull data from terribly architected table On Tue, Oct 23, 2012 at 12:21 PM, Richard Broersma <richard.broer...@gmail.com> wrote: On Tue, Oct 23, 2012 at 12:06 PM, Chris Curvey <ch...@chriscurvey.com> wrote: select my_ids.id , c1.value as col1 , c2.value as col2 , c3.value as col3 , c4.value as col4 , c5.value as col5 from my_ids left join foo c1 on my_ids.id = c1.id left join foo c2 on my_ids.id = c2.id left join foo c3 on my_ids.id = c3.id left join foo c4 on my_ids.id = c4.id left join foo c5 on my_ids.id = c5.id How about: oops - I had some malformed air code SELECT my_ids.id, ARRAY_AGG( ( property, value ) order by (property, value) ) FROM my_ids GROUP BY id ORDER BY id; -- Regards, Richard Broersma Jr. -- Regards, Richard Broersma Jr. You put the above query into a sub-select or CTE (WITH) and then in the outer query you apply whatever where clause you want. If you want to try and help the planner you could do: SELECT some_id FROM foo WHERE property = '.' AND value = '.' UNION ALL SELECT some_id FROM foo WHERE property = '.' AND value = '.' To pre-define which IDs are candidates and then use that information later on in the query. Whether this is a worthwhile effort I have no idea and it may not matter anyway depending on how well the brute-force approach works given your data. David J.
