[Zope-DB] Concurrenct updates in a table, column, row

Dario Lopez-Kästen dario@ita.chalmers.se
Wed, 12 Dec 2001 16:41:23 +0100


I am almost finished porting one of my plsql apps to zope and I have
stumbled upon a transaction/lock thingie that I need help in sorting out.

Here's the example:

I have a table of items. Each item has a name, a column for max items and a
column for booked items.

The column for booked items is updated by several people att the same time.

The process goes like this:

1 - check if there are any items left to book
2 - book the item

in between 1 and 2 there is the possiblity of someone else booking an item.

So the question is, how does zope keep locks in the transaction? What is a
transaction in the Zope sense?

Nayhelp appreciated.


- --------------------------------------------------------------------
Dario Lopez-Kästen     Systems Developer  Chalmers Univ. of Technology
dario@ita.chalmers.se  ICQ will yield no hits    IT Systems & Services