UUID, serial or identity columns for PostgreSQL auto-generated primary keys?
I don't think I've ever seen this mentioned anywhere, but if
you need a unique ID for an entity with not a lot of records
planned (≤10,000,000), why not use a random int64 with
a simple for loop on the application side to catch
the occasional collisions?  Are there any downsides besides
making the application side a tiny bit more complex?