In a ASPNETDB databse, what does an empty ApplicationName of aspnet_Applications table mean?

Reviewing the ASPNETDB of a Membership/WebParts website showed an empty
ApplicationName col for the aspnet_Applications table. Within this same web server, I also
have had several WebPart websites.  The ApplicationNames of the aspnet_Applications
for these web sites dis display the application names, e.g. /Webparts Demo.

I can see the Forms users of the membership website in the aspnet_Users table.  Why I
can not see the ApplicationName of my membership website?   Do I need to add some codes
into <Membership> tags of  the Web.config?

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