The Oracle back-end requires the Oracle OCI client library. (libclntsh.so). The location of this library is specified relative to the ORACLE_HOME value in the operating system environment. CLSQL has tested sucessfully using the client library from Oracle 9i and Oracle 10g server installations as well as Oracle's 10g Instant Client library.
Use
(asdf:operate 'asdf:load-op 'clsql-oracle)
to load the Oracle back-end. The database type for the Oracle back-end is :oracle.