Introducing Pervasive DataExchange

Understanding Pervasive DataExchange and Its Capabilities

This chapter introduces you to Pervasive DataExchange, the DataExchange Editions, and the components included with Pervasive DataExchange. This chapter is divided into the following sections:

DataExchange Overview

DataExchange Editions

DataExchange Components

 

DataExchange Overview

Pervasive DataExchange reliably moves data between two or more Pervasive PSQL databases to maintain warm backup systems, drive data into reporting servers, or synchronize multiple remote databases.

The DataExchange technology works by capturing and sharing changes from one Pervasive PSQL database to other databases in a DataExchange replication network. The Pervasive PSQL Engine is augmented with DataExchange, which adds two software components to a Pervasive PSQL database, the Replication Event Handler and the Replication Engine.

The Replication Event Handler (REH) plugs directly into the Pervasive PSQL database engine. Specifically, the REH is a set of DLLs that operate within the database engine, so if the database is running, the replication event handler is running as well. The database engine activates the REH when there is a change event (insert, update, delete). The REH then makes note of the event in one of its private control tables.

Note The Replication Event Handler is available for both 32 and 64-bit platforms.

The Replication Engine is a separate process that performs the actual replication task. It reads the control tables to determine what records have changed since the last replication session. It then groups these changes into packets and shares them with the other replication engines participating in a DataExchange network. These other engines then apply the updates to their own databases. The replication process occurs either continuously, at scheduled intervals, or on demand. The replication engine does not require constant network connectivity, so DataExchange is suitable for scenarios with intermittent connectivity, like remote users with dialup connections.

Pervasive DataExchange focuses on the two types of data replication:

Providing continuous access to data (Real-Time Backup)

Synchronizing multiple databases (Data Synchronization)

While both capabilities are useful, one typically surfaces as the primary driver for implementing data replication technology in a specific environment.

DataExchange Editions

Pervasive DataExchange is available in two editions—Real-Time Backup and Data Synchronization.

Real-Time Backup Edition

Pervasive DataExchange Real-Time Backup Edition is optimized for quickly and easily maintaining a backup server. It pairs high performance with minimal installation and maintenance. This edition supports one-way replication between a primary server and a backup server.

Real-Time Backup solutions can be onsite or offsite, depending on your needs. Onsite backups ensure your data is protected from hardware failures. Protecting your data means that data recovery time is reduced and downtime is minimal. Solutions that implement an offsite backup server gain protection to your data against catastrophic loss, such as fire, flood or theft.

Data Synchronization Edition

Pervasive DataExchange Data Synchronization Edition is optimized for more complex replication scenarios. This edition supports multiple participating databases and data flowing in multiple directions.

The real-time data replication offered in Data Synchronization ensures all users see the same up-to-the-minute information. The ability to configure flexible topologies allows data flows to match the business organization.

DataExchange Components

Pervasive DataExchange consists of the following primary components:

Replication Engine - used for distributing and applying captured database changes

Replication Event Handler (REH) - used for recording or monitoring database change events

DataExchange Agent - used to provide notification in the event of a replication failure

DataExchange Utilities - used to perform the tasks necessary for replication, such as design and activation

DataExchange Documentation - provides conceptual and instructional information for using Pervasive DataExchange

DataExchange Utilities

Pervasive DataExchange comes with a variety of utilities designed to help you configure and manage the replication process.

Table 1-1

Overview of Pervasive DataExchange Utilities

Utility Type	Utilities Included
GUI-based Utilities	Includes the DataExchange Manager, DataExchange Monitoring Tools, Template Remover Wizard, and Deployment Wizard.
Command-line Utilities	Includes a suite of utilities for performing all phases of design, activation, replication, and deployment.
Services	Monitors data replication, configures replication sessions, and sets logging options. (The set of tools with which you perform these actions are referred to as the DataExchange Monitoring Tools.)

For detailed information on the Pervasive DataExchange Utilities, see Chapter 7, Using the DataExchange Utilities and Services.

DataExchange Documentation

All Pervasive DataExchange documentation, both printed and online, assumes you are familiar with the basics of using a computer, such as clicking and dragging, opening and saving files. If you need assistance with these tasks, please consult the documentation that came with your computer and/or operating system.

You can order printed copies of the documentation from your sales representative.

Getting Started Guides

Pervasive DataExchange includes a printed manual for installation and setup of your product. The manual included with your software is specific to the replication edition you purchased. Depending on the product you purchased, one of the following titles is included in your product package:

Getting Started with Pervasive DataExchange (Real-Time Backup Edition)

Getting Started with Pervasive DataExchange (Data Synchronization Edition)

Both Getting Started guides explain how to install Pervasive DataExchange and guide you through an example replication using two machines.

User’s Guide

The Pervasive DataExchange User’s Guide includes both conceptual and procedural information related to design, activation, and replication. This manual is intended to help you understand the tools and processes used in the replication process.

Pervasive DataExchange User’s Guide includes information applicable to both the Real-Time Backup Edition and the Data Synchronization Edition. It includes reference-based information and task-based instructions that show step-by-step procedures on using the Pervasive DataExchange products.