Product Documentation

FairCom ISAM for C

Previous Topic

Next Topic

Data Management

To use FairCom DB Professional to full advantage, a number of important concepts should be understood. Many of these concepts are common approaches used within the C programming language; some are more specific to FairCom's approach to file access using FairCom DB.

This chapter is a thorough introduction to core data and index component definitions needed to build a successful database application.

  • Data Record Positions - A FairCom DB data file is a collection of data records and other metadata. Simple rules apply to locating the positions of the records in the file.
  • Data and Index Definitions - At the surface, FairCom DB stores data in two types of files: data files and index files. Dive deeper into the file modes in these sections.
  • c-tree Keys - FairCom DB maintains keys in an index file that permits records to be rapidly searched.
  • Key Segment Modes - The Key Segment Mode value tells c-tree how to locate and interpret the information necessary to create an ISAM key segment key.
  • File Recovery - FairCom DB updates information stored in the first record of the file, called the "header," whenever you add a record or key. If this update is interrupted before the header can be updated, c-tree provides functions for file recovery.
  • Advanced Space Reclamation - FairCom DB uses a variable space management index to make available space when a variable-length record changes size and is moved in the file.
  • Online Compact - FairCom DB supports a feature to compact and rebuild indexes while files are opened and in use.
  • Transaction Processing Overview - FairCom DB provides a set of functionality to support transaction processing to ensure that any committed updates to the data and index files will be available even in the event of a system failure. (For more information of transaction processing, see Data Integrity.)
  • Default Temporary File Path in Standalone and LOCLIB Models - FairCom DB supports the ability to set a default path for c-tree temporary files created when rebuilding or compacting c-tree files.
  • Error Handling - This section breaks down the details in the various parts of the error codes returned by c-tree functions.
  • Low-Level Functions - FairCom DB includes a full range of low-level functions that provide developers with complete access to all the features of c-tree.
  • c-tree Constraints - This section details the few constraints that developers should acknowledge when planning an efficient FairCom DB application.

In This Chapter

Data Record Positions

Data and Index Definitions

c-tree Keys

Up to 4X Faster Indexes with Smaller Indexes Using Variable-Length Compressed Key Storage

Key Segment Modes

File Recovery

Advanced Space Reclamation

Online Compact and Rebuild

Transaction Processing Overview

Default Temporary File Path in Standalone and LOCLIB Models

Error Handling

ISAM and Low-Level Functions

c-tree Constraints