You can create an index information file by searching index key information and rearranging the index on the basis of that information. This is called index reorganization.

You can reorganize an index in units of indexes or index storage RDAREAs.

The figure below provides an overview of index reorganization.

Figure 8-12 Overview of index reorganization

• Index information file
  The index information file contains information about an index that was generated by searching index key information.
  
• Control statement file
  The control statement file contains pdrorg's control statements.
  The control statements are used to specify index information.