In versions earlier than 15.5, Replication Server sends each replication operation to the replicate database directly, row-by-row and in log order in a continuous replication mode.
In version 15.5, you can replicate to Sybase IQ from Adaptive Server using real-time loading (RTL). When replicating into Sybase IQ replicate databases with identical database schema, Replication Server achieves better performance than with the continuous replication mode. RTL uses these processes, which result in data reduction:
Compilation – rearranges replicate data, by clustering it by each table, and each insert, update, and delete operation, and then compiling the operations into net-row operations.
Bulk apply – applies the net result of the compilation operations in bulk using the most efficient bulk interface for the net result. Replication Server uses an in-memory net-change database to store the net row changes which it applies to the replicate database.
Instead of sending every logged operation, compilation removes all the intermediate operations and sends only the final states of a replicated transaction. Depending on the application, this generally means a much smaller amount of data is processed.
As Replication Server compiles and combines a larger number of transactions into a group, bulk operation processing improves; therefore, replication throughput and performance also improves.You can control the amount of data that is grouped together for bulk apply by adjusting group sizes.
See Chapter 11, “Sybase IQ Replicate Data Server Issues” in the Replication Server Heterogeneous Replication Guide to connect and replicate to Sybase IQ.
