The recommended approach to querying over SNOMED CT expressions is to first parse, translate (into OWL 2 EL) and classify the expressions together with the precoordinated content of SNOMED CT. A query language (such as the SNOMED CT Expression Constraint Language, SPARQL or DL Query) can then be used to construct queries, which are similarly parsed, translated and executed using an appropriate query engine. For more information about the SNOMED CT expression constraint language, please refer to the Expression Constraint Specification.