Ugh. Is this a correct further paraphrase? * You wanted users to get exceptions which would force them to go to the manual to figure out why they are getting exceptions.
There are less intrusive ways to force users into reading the manual! I really hate software like this; it's a bozo bit that defaults to true. Yeah, transactions are weird on GAE and you pretty much have to read the manual anyways. This additional hurdle doesn't bring any value to the code. If there truly is no behavioral change to single-group transactions when setting XG true, I will hardwire it true and completely hide the "broken bit" from Objectify users. If there's a significant reason to leave XG false for single-group transactions, please let me know. Jeff On Mon, Oct 17, 2011 at 11:05 PM, Max Ross (Google) <max.r...@gmail.com> wrote: > We debated this quite a bit internally. To paraphrase the argument that > carried the day: > XG transactions are awesome but they are not true global transactions. > You're limited to 5 entity groups, you're more likely to see partially > applied transactions in global query results, you can get a concurrency > exception from a read, and there is a performance impact (when you've got > more than 1 entity group enlisted). In short, there's some > surprising/subtle stuff that we really want developers to understand before > they start using this feature. > If we didn't require opt-in it would be too easy for our new developers > (particularly those coming from the RDBMS world where global transactions > are the norm) to miss these important considerations. We want it to be > super easy to use the Datastore, but creating a false sense of simplicity > can do more harm than good in the long run. > Max > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To view this discussion on the web visit > https://groups.google.com/d/msg/google-appengine-java/-/mq8YLNx0kaoJ. > To post to this group, send email to google-appengine-java@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
