On Nov 5, 2012, at 10:22 AM, Kevin Burton <[email protected]> wrote:
> I am calling CreateDocument<Document>() but I suspect that testing if the > document exists first may perform better in the long run. I am using > DreamSeat for my driver but I suspect other drivers have a similar "test". My > problem is that I don't know what to test for and I am unfamiliar with the > available methods. Any one successfully use such a pattern (preferably with > DreamSeat) that tests for existence then creates if the document doesn't > exist? Keep in mind I don't initially have an id. Thank you. I don’t know anything about that particular API, but in general, check-then-create doesn’t work well in a concurrent environment. It’s prone to race conditions where something else creates the resource in between your check call and your create call. (The canonical example is checking whether a file exists, then creating the file, which is a classic old security hole in privileged Unix tools.) —Jens
