GAE does not support transactions across multiple tables. You can put your dal code into a function as in
def mydblogic(*args): .... db.insert....db().update....db(0.select.... and run it with from google.appengine.ext import db as gae gae.run_in_transaction(mydblogic, *args) On Thursday, 29 November 2012 04:18:47 UTC-6, José Manuel López Muñoz wrote: > > I'm making a room reservation system in Web2Py over Google App Engine. > When a user is booking a Room the system must be sure that this room is > really available and no one else have reserved it just a moment before. To > be sure I make a query to see if the room is available, then I make the > reservation. The problem is how can I do this transaction in a kind of > "Mutual exclusion" to be sure that this room is really for this user? > > Thank you!! :) > --