Book Image

Oracle GoldenGate 11g Implementer's guide

By : John P Jeffries, John P Jeffries
Book Image

Oracle GoldenGate 11g Implementer's guide

By: John P Jeffries, John P Jeffries

Overview of this book

Data replication is an important part of any database system that is growing due to today's demand for real-time reporting and regulatory requirements. GoldenGate has recently become Oracle's strategic real-time data replication solution. Until now, very little has been written about how to implement GoldenGate in a production enterprise environment where performance, scalability, and data integrity are paramount. Your days of dismay over the lack of documentation over Oracle GoldenGate are over. Welcome to Oracle GoldenGate 11g Implementer's guide – a comprehensive practical book, which will deliver answers to your questions in a clear, concise style, allowing you to progress effectively in a timeline-driven environment. Based on the author's own experience, this long awaited GoldenGate administration book has all that is required to install, design, configure, and tune data replication solutions suited to every environment. Be the first to master GoldenGate's power and flexibility by reading this unique hands-on implementation companion. Systems need to send data from one system to another in a timely manner to satisfy the ever-increasing need for speed. Regardless of whether you are a novice or an expert – or someone in between – this book will guide you through all the steps necessary to build a high-performance GoldenGate solution on Oracle11gR1. Expert users can dive into key topic areas such as performance tuning or troubleshooting, while novice users can step through the early installation and configuration chapters, later progressing to the advanced chapters. This book is more than an implementation guide. It offers detailed real-life examples, encouraging additional thought and discussion by going beyond the manual. With Oracle GoldenGate 11g Implementer's guide in hand, you'll be designing, installing, and configuring high-performance solutions using GoldenGate in less time than you can say "replicate"
Table of Contents (21 chapters)
Oracle GoldenGate 11 Implementer's guide
Credits
Foreword
About the Author
About the Reviewers
www.PacktPub.com
Preface
GGSCI Commands
GoldenGate Installed Components
The Future of Oracle GoldenGate
Index

More about trail files


Trail files are used by Extract and Replicat processes, and their primary role is for data persistence. One could argue that writing files to what could be deemed as a "staging area" is wasteful and suboptimal. That said, GoldenGate writes to trail files in large blocks minimizing I/O. Furthermore, the architecture provides a guaranteed no data loss solution that is not to be underestimated.

The trail

By default, trail files are in canonical format being unstructured with a header record. Each record is of a variable record length containing the changed data. A trail can contain numerous trail files each having a two-character prefix with a 6 digit sequence number suffix.

An Extract process can write data to many trails. A Replicat can process data from one trail. However, it is possible to configure multiple Replicat processes to handle the workload.

Trail file purging

To "clean up" the processed trail files from a given trail to reduce disk space usage, configure the...