Aggregations and filtering with Elasticsearch

Question

Using ES 1.5.2

Speaking strictly of aggregations, is it better for performance? The query/filter/aggregation returns the exact same result in both cases.

• Filter query and then aggregate.

   { "size":0, "query": {}, "aggs": {} } 

• Or filter inside the aggregate.

   { "size":0, "aggs": { "filter": { "query": {}, }, "aggs": {} } } 

Answer 1

The main difference between filtering and quering ist that filters do not affect scoring.

Filters only reduce the result set size, but there is no relevance scoring on the matched items at all.