Before you configure ECDA Option for Oracle, you should have a basic understanding of how it works:
ECDA Option for Oracle is a Symmetric Multiprocessing (SMP) Sybase Open Server application that uses an Open Server thread for each incoming client connection.
It uses the DirectConnect server to route the incoming client connection to the correct service based on the service name and has one Oracle process for each DirectConnect server.
It does not have a service library but can have multiple services and each service is configured to connect to a different Oracle database. In addition, the DirectConnect server performs SQL transformation and some data translation based on the configuration of the service.
It accesses Oracle databases using the Oracle Call Interface (OCI) application programming interface (API). The OCI allows the ECDA Option for Oracle the ability to manipulate data in an Oracle database.
It communicates with ASE using the server class direct_connect.
Figure 1-1 shows how ECDA Option for Oracle works with ASE, Replication Server and other APIs.
Figure 1-1: ECDA Option for Oracle
As shown in Figure 1-1, the request from a client uses a TCP/IP LAN connection to the DirectConnect server. Based on the incoming server name, the DirectConnect server routes the connection using OCI to the proper Oracle database depending on the configuration properties.