How to set up a has_many :through association with Ultrasphinx


#1

I’m using the Ultrasphinx plugin with Sphinx to add search to my app,
but I’m having a tough time figuring out how to index a
has_many :through relationship. Say, for example, I’m looking at a
relationship like this:

Playlist has_many songs :through => ‘playlistings’

I want to be able to do a song-based search that will return the
Playlists that have those songs. I know I need to use
the :association_sql key to set up the has_many :through join, but my
SQL sauce is weak. Here’s what I have right now, which works only for
the first song:

is_indexed :fields => [{:field => 'name', :as =>

‘playlist_name’}],
:include => [{:association_name => “songs”, :field =>
‘song_name’,
:association_sql => “JOIN
(playlistings, songs) ON (playlists.id=playlistings.playlist_id AND
playlistings.song_id=songs.id)”}]

Unfortunately, like I said, if I do a search by song name, Ultrasphinx
only matches playlists if I search for the first song in a playlist…
searching by all other song names (e.g., the name of the second or
third song in a playlist) returns nothing. Any ideas?

Thanks so much for any help!
Adam


#2

Hey everyone, got it to work! Here’s what I’m using:

is_indexed :fields => [{:field => ‘name’, :as => ‘playlist_name’}],
:concatenate => [{ :class_name => ‘Song’, :field => ‘name’,
:association_sql => “LEFT JOIN playlistings ON
((playlist_id=playlists.id)) LEFT JOIN songs ON
(songs.id=playlistings.song_id)”, :as => ‘song’ }]

Hopefully that’ll help someone out sometime. :slight_smile:


#3

Adam wrote:

Hey everyone, got it to work! Here’s what I’m using:

is_indexed :fields => [{:field => ‘name’, :as => ‘playlist_name’}],
:concatenate => [{ :class_name => ‘Song’, :field => ‘name’,
:association_sql => “LEFT JOIN playlistings ON
((playlist_id=playlists.id)) LEFT JOIN songs ON
(songs.id=playlistings.song_id)”, :as => ‘song’ }]

Hopefully that’ll help someone out sometime. :slight_smile:

Yeah! You help me with this post


#4

Thanx for your information. Wasting half a day I found your post and
this help me so much.

Thanx a lot :slight_smile: