Chapter 9. GT.M Database Structure(GDS)

Table of Contents

Database File Organization with GDS
Database File Header
File Header Data Elements
MLOCK Space
Local Bitmaps
Master Bitmap
Database Structure
Tree Organization
GDS Blocks
GDS Records
GDS Keys
Compression Count
Use of Keys
Characteristics of Keys
Global Variable Names
String Subscripts
Numeric Subscripts

GDS is an FIS proprietary internal database structure used to store global variables and lock resource names. A high-level understanding of GDS can help database administrators correctly interpret GT.M logs/error messages, and maintain database metrics. You should always consult GT.M support (gtmsupport@fisglobal.com) in the unlikely event of getting database integrity issues.

[Note]

This chapter provides a high-level overview of GDS components. A comprehensive description of all the components of GDS is beyond the scope of this chapter.