Ugh. What a tough decision: supporting cross-device sync via CloudKit requires all primary keys to be UUIDs. My tests showed inserts up to 60% slower and queries around 30% slower with a million rows. But not having the option for sync would suck too.

#iOSDev

@Typ0genius Why are queries that much slower? Well indexed UUIDs should be fast to query shouldn't they?
@amyworrall Comparing/inserting strings is much more expensive than numbers.
@Typ0genius @amyworrall Are they represented as Strings though? I would have expected an Int128 representation.