At 23:24 20/05/2015, you wrote: >On Wed, May 20, 2015 at 2:20 PM, Steven M. McNeese ><steven.mcneese at freedomparkdfw.com> wrote: > > Often times people will use GUIDs as primary keys when different > systems need to generate > > rows and then merge together. Like an application that works with > offline clients that push the > > data to a server when the connect. However there are other ways of > accomplishing the same thing. > >For curiosity - Is there a site/blog post somewhere >enumerating/listing these other ways ?
I don't know, but let's say your rowids range from -9223372036854775807 to 9223372036854775807, that's 18446744073709551614 possible rowids. Imagine that in 50 years, the total population on Earth will grow to (say) 50 billion people (I hope it won't!). 18 446 744 073 709 551 614 / 50 000 000 000 = 368 934 881.474 191 032 28 That leaves you the possibility to assign a unique identifier to every potential client on the planet (and a big one) in nearly 369 million servers concurrently without the faintest risk of collision. At this rate, you may limit rowids to only positive integers ... and hire a large army of telemarketers.
