CHAPTER 6Apply Process
When the captured messages reach the intended destination, an Oracle background process called the apply process implicitly consumes—or, generally speaking, dequeues—those messages from the Streams queue.
Typically, the dequeued message is directly applied to the database object where the apply process runs. However, it is possible to configure the apply process to pass the dequeued message as a parameter to a user-defined procedure called the apply handler, which can perform customized actions based on the information in the message. The apply process can also send the message to a remote, non-Oracle database in a heterogeneous replication environment.
The apply process is a very crucial part of the Streams environment. ...