I want to build a search that prioritizes the amount of field matches instead of one field over another. All the fields would have the same boost value and the final score should be calculated by sum matched fields boost. If the full text matches two fields and each field have boost 1, the final score would be 1 + 1 = 2.
Let's use an example:
class Event < ApplicationRecord
searchable do
text :title
text :category
text :artist_name
end
end
Suppose I have two events:
Event 1: Name: "Christmas festival" Artist name: "AC/DC"
Event 2: Name: "New year festival" Artist name: "Queen"
So, if the user searches just "festival", both events are returned with the same score because it matches both event's name. But, if the user searches "festival AC/DC", I want to return Event 1 in the first place or just Event 1 because it matches the event name (festival) and the artist name (AC/DC). While Event 2 just matches the event name (festival). Event 1 score should be 2 while Event 2 score should be 1.
Any suggestion about How can I do that? Is this even possible?
It seems you are mixing up scoring and boosting, I think your question should be titled Compute total score by summing each field score (regardless of the boosts).
Field scores are computed based on field matches, and they can be applied arbitrary set of additive or multiplicative boosts (functions and/or matching subqueries). But in the end what you want is to compute the global score by summing each field score, not the boosts themselves.
DisMax query parser for example precisely allows you to control how the final score is computed using the tie (Tie Breaker) parameter :
The tie parameter specifies a float value (which should be something much less than 1) to use as tiebreaker in DisMax queries.
When a term from the user’s input is tested against multiple fields, more than one field may match. If so, each field will generate a different score based on how common that word is in that field (for each document relative to all other documents). The tie parameter lets you control how much the final score of the query will be influenced by the scores of the lower scoring fields compared to the highest scoring field.
A value of "0.0" - the default - makes the query a pure "disjunction max query": that is, only the maximum scoring subquery contributes to the final score. A value of "1.0" makes the query a pure "disjunction sum query" where it doesn’t matter what the maximum scoring sub query is, because the final score will be the sum of the subquery scores. Typically a low value, such as 0.1, is useful.
In your situation you need a disjunction sum query so you might want to set the tie to 1.0.