Editing Chemical database (section)

== Tools ==

The computational representations are usually made transparent to chemists by graphical display of the data. Data entry is also simplified through the use of chemical structure editors. These editors internally convert the graphical data into computational representations.

There are also numerous algorithms for the interconversion of various formats of representation. An open-source utility for conversion is [[OpenBabel]]. These search and conversion algorithms are implemented either within the database system itself or as is now the trend is implemented as external components that fit into standard relational database systems. Both Oracle and [[PostgreSQL]] based systems make use of '''cartridge technology''' that allows user defined datatypes. These allow the user to make [[SQL]] queries with chemical search conditions (For example, a query to search for records having a phenyl ring in their structure represented as a SMILES string in a SMILESCOL column could be

<syntaxhighlight lang="sql">
 SELECT * FROM CHEMTABLE WHERE SMILESCOL.CONTAINS('c1ccccc1')
</syntaxhighlight>

Algorithms for the conversion of [[IUPAC]] names to structure representations and vice versa are also used for [[text mining|extracting structural information from text]]. However, there are difficulties due to the existence of multiple dialects of IUPAC. Work is on to establish a unique IUPAC standard (See [[International Chemical Identifier|InChI]]).