Overview

This document provides a guide for installing bidirectional ProSync in TAC and Single configurations.

Scenario

Note

TAC and SINGLE environments must be set up in advance.

ProSync Installation and Execution

Refer to the ProSync installation and execution documents.

Method

The Extract process extracts the Redo Log from the extraction database (SRC DB) corresponding to the SRC DB.

Extraction is performed through the Log Reader Library for each DB, and if necessary, extraction may also be performed using separate log analysis functions provided by each DB. The extracted data is delivered to the Apply process.

Data is usually recorded in units of records (i.e., DML units), and this data must be collected and applied for each transaction by the Apply process. Therefore, the Apply process receives records and manages them by collecting them per transaction.

Afterwards, when a record corresponding to a commit is received, the corresponding transaction is applied.

※ When Change Data extracted by ProSync on one side is applied, from the perspective of the Target Database, the changed data is recognized as newly generated, so the corresponding history is recorded in the Redo Log. At this time, if the corresponding content is extracted again by the ProSync on the other side and delivered to the Source Database, the data may be redundantly applied.

Therefore, it is necessary to take measures to prevent such redundant application, and ProSync supports bidirectional synchronization by defining different policies for each DB.