Boolean retrieval

Boolean retrieval (after George Boole ) is a simple form of information retrieval , in which the words of a search query are linked with Boolean operators (AND, OR, NOT).

The documents in an information retrieval system with Boolean retrieval are mapped to simple sets of words (index terms) when they are indexed . So there is no weighting of the individual index terms, as is the case, for example, with vector space retrieval . When a search query is made, all documents are returned that contain a combination of words that you are looking for.

There is no ranking of the result set. Boolean retrieval is relatively easy to implement and was used with the Uniterm system as early as the 1950s . However, the search requires knowledge of the search terms on the part of the user, which is why the method is more likely to be used in conjunction with controlled indexing and / or in conjunction with suitable user interfaces ( e.g. drilldown ).

Many search engines with more sophisticated retrieval methods also offer Boolean operators.

Extensions to Boolean retrieval are fuzzy retrieval and extended Boolean retrieval .