Summary

Using an Oracle database requires the installation of Oracle instant clients on the Users' machines.
The Client libraries provide the necessary network connectivity.

User Manual:
Oracle Server Setup

Connection string

Input Server Name:

<host>:<port>/<serviceName> (ex. "127.0.0.1:1234/serviceName")

OR

(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=<host>) (PORT=<port>))(CONNECT_DATA=(SERVICE_NAME=<serviceName>)))

https://docs.oracle.com/cd/B28359_01/network.111/b28317/tnsnames.htm

Connecting to Oracle

We do not use any specific technology to connect to our DBs but use a third-party ORM (Object-Relational Mapping) framework from DevExpress: XPO
Through this framework, we can connect to Oracle, SQL Server, and SQLite as a black box without knowing and caring about the details of the lower levels.

Connecting to SAP

We used a third-party library for connection (Theobald's ERPConnect).
So we do not hardcode any port to be used. There are some standard ports defined for SAP connection that are automatically used by ERPConnect, which are documented on their homepage https://theobald-software.com/en/erpconnect
The Performer Suite connects to SAP via ERPConnect, we do not directly use any specific port, or JDBC.

Troubleshooting

See: ORACLE: Connection fails

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