Sunspot Solr index time boost

Question

I try to use document boost on index time, but it seems, that it hasn't any effect. I've set up my model for Sunspot like

Spree::Product.class_eval do
  searchable :auto_index => true, :auto_remove => true do
    text :name, :boost => 2.0, stored: true
    text :description, :boost => 1.2, stored: false
    boost { boost_value }
  end
end

The boost_value field is a field in the database, where a user can change the boost in the frontend. It gets stored at index time (either the first time I build the index, or when a product is updated). I have about 3600 products in my database, with a default boost_valueof 1.0. Two of the products got different boost_values, one with 5.0 and the other with 2.0.

However, If I just want to retrieve all products from Solr, the document boost seems to have no effect on the order or the score:

solr = ::Sunspot.new_search(Spree::Product) do |query|
  query.order_by("score", "desc")
  query.paginate(page: 1, per_page: Spree::Product.count)
end

solr.execute
solr.results.first

The Solr query itself looks like this:

http://localhost:8982/solr/collection1/select?sort=score+desc&start=0&q=*:*&wt=xml&fq=type:Spree\:\:Product&rows=3600&debugQuery=true

I've appended a debugQuery=true at the end, to see what the scores are. But there are no scores shown.

The same things happens, when I search for a term. For examle, I have 2 products that have a unique string testtest inside the name field. When I search for this term, the document boost has no effect on the order.

So my questions are:

• Can per document index time boosting be used based on a database field?
• Does the document boost has any effect for q=*:*?
• How can I debug this?
• Or do I have to specify, that solr should involve the document boost?

Answer 1

In solr, the boosts only apply to text searches, so it applies only if you do a fulltext search. Something like this:

solr = ::Sunspot.new_search(Spree::Product) do |query|
  fulltext 'somesearch'
  query.order_by("score", "desc") # I think this isn't necesary
  query.paginate(page: 1, per_page: Spree::Product.count)
end

If you want to boost certain products more than others:

solr = ::Sunspot.new_search(Spree::Product) do |query|
  fulltext 'somesearch' do
    boost(2.0) { with(:featured, true) }
  end
  query.paginate(page: 1, per_page: Spree::Product.count)
end

As you see, this is much powerfull than boosting at index time, and you could put different boostings for different conditions, all at query time with no need of reindexing if you want to change the boost or the conditions.