Here is a list of some of the most important (full list on the facets page): Mapping is the process of defining how a document should be mapped to the Search Engine, including its searchable characteristics such as which fields are searchable and if/how they are tokenized.
In Elastic Search, an index may store documents of different “mapping types”.
There are two options for how a query is sent to the search endpoint: In addition, and somewhat confusingly, Elastic Search distinguishes between sub-components that are “queries” and those that are “filters”.
Since 0.3, Jongo uses Mongo Java driver at a deeper level to enhance performance.
Instead of converting results into strings and unmarshalling strings into objects, it works at level (query marhalling works the same since 1.0).
Elastic Search is a great open-source search tool that’s built on Lucene (like SOLR) but is natively JSON RESTful.
Its been used quite a bit at the Open Knowledge Foundation over the last few years.