Spring Solr提振问题

Question

Am using Spring Solr with Groovy.

Have an issue when I try to boost results.

To explain, consider a simplified online shopping domain, where the indexed entity is Product.

The user has a shoppingBasket and a wishList, each of which are simple Lists of Product codes (ie List<String>). The two Lists are first processed to ensure they are distinct and unique.

A simple search might be for a keyword String in the Products' text (a composite field made using copyField, containing its description and title).

The requirement is for the results to list every Product where the keyword is matched in its text with any of those that are in the shoppingBasket displayed first, then any that are in the wishList, followed by any others.

The issue encountered is that although some boosting is taking place and results from the wishList and shoppingBasket each grouped, the shoppingBasket matches are not always displayed ahead of the wishList matches.

Depending on the products in each List, it sometimes displays in the order:

all wishList matches, all shoppingBasket matches, all other matches

instead of the expected:

all shoppingBasket matches, all wishList matches, all other matches

The boosting is applied using these criteria:

boostingCriteria = new Criteria('productCode_s').in(shoppingBasket).boost(2.0f)
boostingCriteria = boostingCriteria.or(
      new Criteria('productCode_s').in(wishList).boost(1.0f) )

Having seen this similar issue I commented out a Sort that was being added to the PageRequest, that made no difference.

I also used the @Score annotation to include the score in the results returned. Inspecting those, I can see that solr gives the same identical score to all matches in either the shoppingBasket or wishList. All matches outside of those lists get another lower score (identical between them).

Have tried different values for the boosts (10000.0f and 5000.0f respectively) to no avail. It did produce a different score but it was still identical between all matches in either the shoppingBasket or wishList.

Even simplifying the search down to just the boosting criteria alone, the ordering is still out.

Any ideas would be appreciated.

Answer 1

Through trial and error I found the solution was to use the .connect() method as follows.

boostingShoppingBasket = new Criteria('productCode_s').in(shoppingBasket).boost(10.0f).connect()
boostingWishList = new Criteria('productCode_s').in(wishList).boost(2.0f).connect()

Then OR these together.

Where there were other search criteria to apply too (eg that the product description contained certain text), these had to be ANDed with the boosting criteria before wrapping with the connect, such that in the more complex situation, I'd end up with the following (assuming the createSearchCriteria(searchCommand) method returns the basic search criteria):

boostingShoppingBasket = new Criteria('productCode_s').in(shoppingBasket).boost(10.0f)
boostingShoppingBasket = boostingShoppingBasket.and(createSearchCriteria(searchCommand)).connect()

boostingWishList = new Criteria('productCode_s').in(wishList).boost(2.0f)
boostingWishList = boostingWishList.and(createSearchCriteria(searchCommand)).connect()

Criteria criteria = createSearchCriteria(searchCommand)
   .or(boostingShoppingBasket).or(boostingWishList)