Transaction replication maintains data in separate databases called replicate databases. Replicate databases contain accurate, current copies or subsets of data from the primary database.
Replication of data allows slower, process-intensive decision support queries to run against the same data without slowing mission-critical, on-line transaction processing (OLTP) applications.
Figure 1-1 shows a generic replication system and its components.
Figure 1-1: Replication system overview
The following sections introduce the basic concepts of transaction replication and describe the following elements of a typical replication system:
