A percolator index stores queries that should be checked later against newly indexed documents. In a bookstore search, an unsuccessful search for “Python” can be saved so the user can be notified when “Python in Action” becomes available. section 12.9.4
Create and use the index in three steps:
- Define a query field with the percolator data type; mirror relevant document fields such as name and tags in the mapping. section 12.9.4
- Index the failed user query as the query value rather than as an ordinary document. section 12.9.4
- Run a percolate query with the newly available document to find stored queries that match it. section 12.9.4
