On the Advanced tab, which is present when you have selected a new or existing index in a database, you'll find some read-only properties of this index, mainly for advanced users.

On the current tab you'll find the following data:

Internal name

This name is copied from the option with the same name on the Index properties tab.

Index file

This property is obsolete for Axiell Collections. You may ignore it.

Physical type

The data encoding type of this index on programming level.

Physical size

The size of the above mentioned physical type of this index in bytes.

Reindexing required

You must build up an index by reindexing it after you have set all the properties of a blanc new index, or when you have modified the properties of an index definition in any way. To help you remember if you already reindexed this index or not, after you modified its settings, this option will be marked if you haven't reindexed yet.