MacSQL requires the Oracle client driver to be installed. Instructions to download and install this driver are available at http://www.rtlabs.com/support/oracleinstall.html.
The Oracle OCI driver uses entries in a file named tnsnames.ora to open a connection.
After installing the driver (per our instructions), the tnsnames.ora file can be found at
/Library/Oracle/network/admin/tnsnames.ora. This file
must be configured before you can use MacSQL to connect to an Oracle
server. All entries in the file will be listed in the Host menu of
the New Connection window. If you need help configuring the tnsnames.ora file,
you should ask your Oracle server administrator for assistance.