That said, how do you deal with transactions? It was my impression that MongoDB doesn't really support ACID transactions. Did you find a workaround?
I know from prior experience working on a major eCommerce store that there can be really taxing loads on the database server, right around Black Friday, and having inconsistent writes could really be disastrous. Have you tested your transactions for consistency under load?
To start, I will say we haven't run into any issues relating to consistency under load. We do have a plan for dealing with it, using an optimistic locking mechanism (where each document has a revision number and an update requires it), but as an early project we haven't had the chance to put it up against high load for a long period of time.
Also, I'm pretty confident MongoDB is going to introduce an easier mechanism for document locking in the near future.
It's difficult to find the right back-end solution that can easily scale with a business and demand. I saw this post a month ago and think it looks pretty promising and might be something you could take advantage of here. http://news.ycombinator.com/item?id=4294719
Currently it's in alpha testing and promises multi-key ACID transactions. And also introduces a really interesting layers concept. http://www.foundationdb.com/#layers
That said, how do you deal with transactions? It was my impression that MongoDB doesn't really support ACID transactions. Did you find a workaround?
I know from prior experience working on a major eCommerce store that there can be really taxing loads on the database server, right around Black Friday, and having inconsistent writes could really be disastrous. Have you tested your transactions for consistency under load?