The current `multi_match` docs contain an erroneous reference to the `combined_fields` query. This updates the reference to reference the correct query.
Relates to https://github.com/elastic/elasticsearch/pull/76893
In the upcoming Lucene 9 release, `indices.query.bool.max_clause_count` is
going to apply to the entire query tree rather than per `bool` query. In order
to avoid breaks, the limit has been bumped from 1024 to 4096.
The semantics will effectively change when we upgrade to Lucene 9, this PR
is only about agreeing on a migration strategy and documenting this change.
To avoid further breaks, I am leaning towards keeping the current setting name
even though it contains `bool`. I believe that it still makes sense given that
`bool` queries are typically the main contributors to high numbers of clauses.
Co-authored-by: James Rodewig <40268737+jrodewig@users.noreply.github.com>
This PR introduces a new query called `combined_fields` for searching multiple
text fields. It takes a term-centric view, first analyzing the query string
into individual terms, then searching for each term any of the fields as though
they were one combined field. It is based on Lucene's `CombinedFieldQuery`,
which takes a principled approach to scoring based on the BM25F formula.
This query provides an alternative to the `cross_fields` `multi_match` mode. It
has simpler behavior and a more robust approach to scoring.
Addresses #41106.
