Release 10.1A: OpenEdge Getting Started:
Database Essentials

Rebuilding indexes

The purpose of an index rebuild, PROUTIL IDXBUILD, is to increase index efficiency and to correct errors. Use this utility when index corruption forces a rebuild of an index or you can take your database offline for index maintenance. Your database must be offline when the index rebuild utility is run. You can use a combination of online utilities, including index fix and index compact, to approximate the effect of an index rebuild.

You will get significantly better organization within the indexes by sorting the indexes prior to merging them back into the database. You can do this by opting to sort when running the utility. Be aware that sorting requires substantial disk space (50 to 75 percent of the space of the entire database when choosing all indexes).

You cannot choose a level of compression with index rebuild. The utility tries to make indexes as tight as possible. While high compression is good for static tables, dynamic tables tend to experience a significant number of index splits right after this utility has been run. This affects the performance of updates to the table. Even with the decrease in update performance, the overall benefit of this utility is often desirable. The performance hit is limited in duration, and the rebuild will reduce I/O operations and decrease scatter of the indexes.