[thelist] trying to learn about locking (was: Re: CF Session Variables)

[Susan Wallace]

Hi again,

I'm sorry to keep dragging this out, but now I am at a point where I would 
like to have something clarified for me, please. :)

I wrote before about the e-commerce application that had been somehow 
corrupted by what I suspected was a price that had been entered as $0.00. 
(the issue was that customers were having other people's personal 
information show up in their forms - some were cookies, others were 
sessions..) In looking into this, it was suggested that the session locks 
be changed.

This is what is in the application:

<cflock name=#Session.SessionId# timeout="20"
  type="READONLY"> <cfset itemnumber =
  Session.Basket.CurrentRow> <cfset Product_ID =
  Session.Basket.Product_ID> </cflock>

And Raymond suggested changing it to this:

  change: NAME="#Session.SessionID#" to
SCOPE="Session". This is safer on a 4.5.1 box.

I do understand the difference here. :)

I am confused by the whole thing because there were too many variables 
involved, and I have spent hours trying to come up with a graceful solution 
for "repairing" the damage. After mulling this over (and pulling out hair) 
I have a question.

IF the price of zero was in fact NOT an issue.

and IF the CF server (4.5.1) this application was running on is in fact 
VERY overloaded

Is it still possible for this "session swapping" to go on even when Locks 
(either the Name= OR Scope=) are in place?

I emphasize the if's here not to seem rude, but to point out that I know 
there are too many variables here, and I don't have the answers for them.

Here is my scenario: If I can get a copy of the database from backup and in 
effect restore the customer information from that point, and then left the 
store on that same overloaded server, without having a product with a price 
of zero, is it still possible that the corruption will occur because of the 
overload, even with the session locking in place?

I know I restated that twice, I hope one makes more sense than the other.

I am working on moving the site to a less crowded server, replacing the 
locks as Raymond suggested, and considering using Client variables instead 
of session variables since this is on a shared server and I can't control 
what else is put on it. This one goes down as the second biggest headache... :/

Thank you VERY much for the help!

Susan Wallace

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