Begining of Java Servlet Inteface

Chris Shenton
14 May 2001 12:11:35 -0400

Christopher Molnar <> writes:

> Can you give me a quick example of a user scenario where this may
> happen? As I am trying to work through this and write some java beans
> for transactions I am not comming across anyplace where transactions are
> really an issue. I may be missing something in my thinking though.

What if my S.O. and I are both accessing the DB from different
locations, both making changes to the same data -- perhaps a specific
account.  Wouldn't this result in a race-condition? 

She gets in first and sees a valid statment.
I connect and see the same.
She withdraws all the money, transferring to her Swiss bank account. :-)
I try to pay a bill (inter-account transfer) from my now-obsolete view;
  if it tries to update the DB,
  the update should fail and all my transactions should roll-back.

This is not a great example, and the fact that GnuCash should
*repreresent* the physical/financial reality makes this not so
important as a banking system where such a race-condition could lead
to real financial difficulties.

I know Oracle and Postgres can support true transactions with
roll-back;  I haven't follwed MySQL's most recent progress on this.