Secondary indexing and logical relationships

Secondary indexing and logical relationships are techniques that can change your application program's view of the data. The DBA makes the decision about whether to use these options.

Examples of when you use these techniques are:

• If an application program must access a segment type in a sequence other than the sequence specified by the key field, secondary indexing can be used. Secondary indexing also can change the application program's access to or view of the data based on a condition in a dependent segment.
• If an application program requires a logical structure that contains segments from different databases, logical relationships are used.