An information retrieval (IR) query language is a query language used to make queries into database, where the semantics of the query are defined not by a precise rendering of a formal syntax, but by an interpretation of the most suitable results of the query.
Of importance in IR query languages is weighting and ranking, "relevance-orientation", semantic relativism and logic-based probabilism.
An example of an IR query language is contextual query language (CQL), a formal language for representing queries to information retrieval systems such as web indexes, bibliographic catalogs and museum collection information.
References
Information retrieval query language Wikipedia(Text) CC BY-SA