Rails - Table join with specified fields in select

Rails - Table Join With Specified Fields in Select

Sunday, November the 1st, 2009 | Comments

Figured this out after a lot of monkeying-around (I mean script/console).

Situation:

I have two tables (Revisions has_many Inputs)
I can load Revisions and then for each I can find Inputs, but quickly found out that for my situation, it leads to a lot of queries. So I want to load the required fields from both tables together

:joins is the only way to do this, using :includes does NOT respect the select clause. Here a gist:

metrics_with_inputs = Revision.find( :all, :conditions => { :id => self.revisions.map { |r| r.id } }, :select => 'revisions.metric, revisions.snap_date, revisions.updated_at, inputs.author, inputs.as_of_date, inputs.units', :joins => 'join inputs on inputs.revision_id = revisions.id', :order => 'revisions.metric, revisions.snap_date, revisions.updated_at' )

Admittedly, this is hacky, too hacky for my comfort. Comment/suggest a better/cleaner solution?

Note: Found out that there is a gem to do this: ar-select-with-include

Arnab's Universe

... and all the parallel ones.

Rails - Table Join With Specified Fields in Select