authorize_check_query and authorize_reply_query

[Guido]

Hello list, I'm using freeradius and have some doubts abot these steps.

authorize_check_query = "store_check_query 
'%{Stripped-User-Name:-%{User-Name}},''''
authorize_reply_query = "store_check_query 
'%{Stripped-User-Name:-%{User-Name}},''''

At this moment I'm using both authorize (check and reply),  executong in 
both steps an store procedure.

The question is if  is madatory use both auth or is possible use only one of 
them. i.e. only  authorize_reply_query

Thanks in advanced

Guido