[Info-vax] OT: Record locking for web transactions

[JF Mezei]

On 14-02-18 17:33, Jan-Erik Soderholm wrote:

> What if the user takes 15 min to think about and update the data
> before clicking the "Send" button? And what if if another user
> updated the data after 12 minutes?

The app would notice an expired lock, and issue mssage to user.


> I think that most applications simply make the assumption that
> two users will not be updating the same record at the same time.
> And if they do anyway, the last one clicking "Send" will win. :-)

This is the WIndows Weenie type of thinkink as they were brought up with
single user systems and never really understand the need for locking.

But if you are building a serious application, can you really afford to
ignore locking ?


> You can have an transaction log where the support can trace what
> happend in the case of one of the users calling saying that his
> updates never was saved.

Won't help if 2 widthdrawals for the total amount in the account were
made due to lack of locking. The account balance will show "$0" despite
you having handed out the balance twice and it would take a long time to
trace it back.

> But, *that* has little with the web to do. Any ordering application
> could behave in the same way. :-)

Yes it does because of the stateless web transaction model.