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  • Free software session presentation
  • Open Access


Journal of Cheminformatics20102 (Suppl 1) :F3

  • Published:


  • Relational Database
  • Core Area
  • Chemistry Development
  • Processor Core
  • Free Software


Registration, indexing and searching of chemical structures in relational databases is one of the core areas of cheminformatics.

However, little detail has been published on the inner workings of search engines and their development has been mostly closed-source. We decided to develop an open source chemistry extension for Oracle, the de facto database platform in the commercial world.


Here we present OrChem, an extension for the Oracle 11G database that adds registration and indexing of chemical structures to support fast substructure and similarity searching. The cheminformatics functionality is provided by the Chemistry Development Kit. OrChem provides similarity searching with response times in the order of seconds for databases with millions of compounds, depending on a given similarity cut-off. For substructure searching, it can make use of multiple processor cores on today's powerful database servers to provide fast response times in equally large data sets.


OrChem is free software and can be redistributed and/or modified under the terms of the GNU Lesser General Public License as published by the Free Software Foundation. All software is available via

Authors’ Affiliations

EMBL Outstation - Hinxton, European Bioinformatics Institute, Wellcome Trust Genome Campus, Protein and Nucleotide Database Group, Chemoinformatics and Metabolism Team, Hinxton, Cambridge, CB10 1SD, UK


© Mark; licensee BioMed Central Ltd. 2010

This article is published under license to BioMed Central Ltd.