SQLite is the FreeSWITCH default. Databases are located in the freeswitch/db directory.
Postgres native support will be in FreeSWITCH 1.2.4 but has been available in the Main GIT branch.
libpq and the associated dev packages are required
To enable PostgresSQL as a native client in FreeSWITCH you must enable it during the build when running configure.
Under the Settings area insert the following line
<param name="core-db-dsn" value="pgsql;hostaddr=127.0.0.1 dbname=freeswitch user=freeswitch password= options='-c client_min_messages=NOTICE' application_name='freeswitch'" />