Description of the illustration strms034.eps
This illustration shows the following process for row migration during apply:
-
A user makes the following update to a table:
UPDATE hr.employees SET department_id=50 WHERE employee_id=145;
-
The source database records the change in the redo log.
-
A capture process captures the change and enqueues it as an LCR at the source database.
-
The propagation propagates the LCR to a queue at the destination database.
-
An apply process dequeues the LCR at the destination database and transforms the
UPDATE
into anINSERT
because the change satisfies a subset rule. -
The apply process applies the change as an
INSERT
into anhr.employees
subset table. This subset table contains rows only for employees with adepartment_id
equal to50
.