Skip to main content

Extent (Index Keyword)

Defines an extent index.


To specify that this is an extent index, use the following syntax:

Index name [ Extent ];

Where name is the name of the index. It is useful to follow a naming convention so that indexes can be easily distinguished from properties. For example, you could include IDX at the end of all index names.

Otherwise, omit this keyword or place the word Not immediately before the keyword.


If you are using bitmap indexes, then an extent index is automatically added and there is no need to define one.


An extent index is used to keep track of which object instances belong to a subclass.


The default for the Extent keyword is false.

See Also

FeedbackOpens in a new tab