This illustration shows an Oracle Streams two-database replication environment that includes the following Oracle databases:

• sync1.example.com

• sync2.example.com

The sync1.example.com database has the following Oracle Streams components configured:

• The following queues: capture_queue and apply_queue.

• A synchronous capture named sync_capture that captures DML changes to the hr.employees and hr.departments tables. The synchronous capture enqueues these changes into the local capture_queue queue.

• A propagation named send_emp_dep that sends changes from the local capture_queue queue to the apply_queue queue at sync2.example.com.

• An apply process named apply_emp_dep that dequeues changes that originated at sync2.example.com from the apply_queue queue and applies them to the hr.employees and hr.departments tables.

The sync2.example.com database has the following Oracle Streams components configured:

• The following queues: capture_queue and apply_queue.

• A synchronous capture named sync_capture that captures DML changes to the hr.employees and hr.departments tables. The synchronous capture enqueues these changes into the local capture_queue queue.

• A propagation named send_emp_dep that sends changes from the local capture_queue queue to the apply_queue queue at sync1.example.com.

• An apply process named apply_emp_dep that dequeues changes that originated at sync1.example.com from the apply_queue queue and applies them to the hr.employees and hr.departments tables.