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    Examine Terminology

    Describes the different terms/names used throughout Examine

    This document has been verified for Umbraco 7.

    If you are using Umbraco 9 or later versions, please refer to the note on the Examine documentation landing page for more details.


    An Index is the repository that stores searchable data, generally Examine uses Lucene as its index repository but if you really wanted it is possible to use any repository, though this would require writing a lot of code.

    The 3 basic parts

    Examine is made up of 3 basic parts:Indexers, Searchers and Index Sets. Each one of these components requires exactly 1 of the other components, there is a 1 to 1 to 1 ratio between these objects. For example, each Index Set will have an associated Indexer and Searcher.


    An indexer in Examine is the object that performs the storing data into the index. The most basic interface that defines an indexer is Examine.IIndexer. An indexer's functionality is to: Add or update index data for a data entity, delete index data for a data entity, re-index all data based on a specified data source.


    A searcher in Examine is the object that performs the searching of data that is stored in the index.The most basic interface that defines a searcher is Examine.ISearcher. Examine has the capability to search based on its own Fluent Api, or by querying directly to Lucene using raw lucene search syntax.

    Index Set

    An index set is what defines an index, where the index is saved and how the information is stored in the index.

    Naming conventions

    It is important to note the naming conventions above. Your Indexer, Searcher and associated Index Set must all be named according to convention so that they match. With the above examples the naming conventions are:

    ExternalIndexer ExternalSearcher ExternalIndexSet

    Notice that the prefix is all the same, this is a requirement. The suffixes must also match so that the indexer name is suffixed with Indexer, the searcher is suffixed with Searcher and the index set is suffixed with IndexSet.