Mysql--just clarification

["ravi reddy" <mravikreddy@gmail.com>]

Hi Users

              I am using Freeradius-1.1.2 with mysql database:

In sql.conf i found these following 

accounting_stop_query 
and 
accounting_stop_query_alt

one have update querie and the later have the insert query  this is became a lots confusion to me..

can any body please explain me why these two 

i think only one is enough just update

any suggestions please:-)