13. The computer system of claim 8 , wherein converting the database query into a SPARQL query format comprises determining that the database query can be converted into more than one equivalent SPARQL query, and selecting the fastest one from among the more than one equivalent SPARQL queries.
8. A computer system for accessing an RDF repository through a SPARQL gateway, comprising: a computer processor to execute a set of program code instructions; and a memory to hold the program code instructions, in which the program code instructions comprises program code to perform, receiving, by a SPARQL gateway, a database query, the database query received in a first query language format; converting the database query into a SPARQL query format; submitting the converted query to a SPARQL endpoint; receiving by the SPARQL gateway, SPARQL query results from the SPARQL endpoint; and transforming the SPARQL query results into a format corresponding to the first query language format, wherein the format is not an XML format.