ASP.Net Session Question

Question

I wanna ask, if my ASP.Net Application is using SQL Server for session storing, when I getting the session id with Session.SessionID, it returns a 24 chars string. And I try to use this 24 chars string to find record in the SQL Server, I found that the record does not exist. I found that the Session ID stored is filled with a sequence number to form a 32 chars string. For example, Session.SessionID get ----- ehlbzl55yud4mojm4a4ui345 The SQL Server will store ----- ehlbzl55yud4mojm4a4ui34500000001 How can I know that the SessionID is valid by verifiying it in the SQL Server with the Session.SessionID (24 chars string) I need to append 7 zero and 1 one in the Session.SessionID to search in the SQL Server. But I concern that, is that the ASP.Net must generate 7 zero followed by 1 one in the SessionID to store in the SQL Server, or any other alorigthm to do that? Thanks for the helps. Don