Description of the illustration strms034.eps

This illustration shows the following process for row migration during apply:

  1. A user makes the following update to a table:

    UPDATE hr.employees SET department_id=50 WHERE employee_id=145;
  2. The source database records the change in the redo log.

  3. A capture process captures the change and enqueues it as an LCR at the source database.

  4. The propagation propagates the LCR to a queue at the destination database.

  5. An apply process dequeues the LCR at the destination database and transforms the UPDATE into an INSERT because the change satisfies a subset rule.

  6. The apply process applies the change as an INSERT into an hr.employees subset table. This subset table contains rows only for employees with a department_id equal to 50.