anchor.diff:  <1> The query with id `1` matches our document.
   <2> The `_percolator_document_slot` field indicates which document has matched with this query.
       Useful when percolating multiple document simultaneously.
  +
  +TIP: To provide a simple example, this documentation uses one index `my-index` for both the percolate queries and documents.
  +This set-up can work well when there are just a few percolate queries registered. However, with heavier usage it is recommended
  +to store queries and documents in separate indices. Please see <<how-it-works, How it Works Under the Hood>> for more details.
   
   [float]
   ==== Parameters
  
positive.code:     query with `_name` parameter set to `query1`.
  
  [float]
  ==== How it Works Under the Hood
  
  When indexing a document into an index that has the <<percolator,percolator field type>> mapping configured, the query
  
negative.code: 
  NOTE: The above example assumes that there is a `query` field of type
  `percolator` in the mappings.
  
  Given the design of percolation, it often makes sense to use separate indices for the percolate queries and documents
  being percolated, as opposed to a single index as we do in examples. There are a few benefits to this approach:
  
  - Because percolate queries contain a different set of fields from the percolated documents, using two separate indices
  allows for fields to be stored in a denser, more efficient way.
  - Percolate queries do not scale in the same way as other queries, so percolation performance may benefit from using
  a different index configuration, like the number of primary shards.
  