To access a database, you must connect to the database. You can connect to one or more databases during a single OpenEdge session. You can also start an OpenEdge session without connecting to a database, and connect later.

Note: On UNIX, the kernel configuration's file descriptor limit imposes a practical limit on connected databases. "Unable to open file" or "Unable to allocate I-Node" messages often mean your system's file descriptors have been exhausted. "Unable to allocate shared memory" often means your shared memory has been exhausted on your system. For more information about kernel configurations, see Manage the OpenEdge Database.