Sigh. Found another example. A table with 15 million entries and a unique key on filesystem location for things users created via a web interface.
Entries all begin with /usr/home/ ... This one is frequently sorted as batch operations against the files are performed in alphabetical order to reduce conflict issues that a random ordering may cause between jobs. regards, Rod On Thu, Aug 7, 2014 at 5:23 PM, Rod Taylor <rod.tay...@gmail.com> wrote: > > On Thu, Aug 7, 2014 at 3:06 PM, Peter Geoghegan <p...@heroku.com> wrote: > >> I think that pre-sorted, all-unique text datums, that have all >> differences beyond the first 8 bytes, that the user happens to >> actually want to sort are fairly rare. > > > While I'm sure it's not common, I've seen a couple of ten-million tuple > tables having a URL column as primary key where 98% of the entries begin > with 'http://www.' > > So, that exact scenario is out there. >
