Reorganising the Database

The database reorganisation utility (REORGDB) is used for one of three reasons:

• A structural change requiring a complete reorganisation has been made to the database.

• The information in the data or index file has become fragmented and requires rebuilding. If DBCHECK shows a data file usage below 90% or index file usage below 60% the database will benefit from being reorganised. As of release 4.622 REORGDB can improve the performance of very large databases enormously. You should consider running REORGDB frequently, especially on head-office databases.

• An index for a table requires rebuilding because it has been newly switch on using SETLINK.

This section is divided into the following topics:

• Speeding Up Reorganisations

• Advanced Database Properties

• Choosing a Reorganisation Option

  • Reorganising with Compression

  • Removing Database Holes

  • Reorganising with Rebuild

  • Optimising the Index File

  • Reorganising an Index

  • Deleting Application Data

• Sorting The Database Data File

• Sorting the Entire Data File

• Reorganising to Remove Corruptions

• Reorganising to Remove Deletions