Collation

[blm768]

We need to define a sane collation order for ShortPhoneNumber objects. Right now, we're just ordering by the packed binary data, but that won't always match the natural collation order of phone numbers.

[singingwolfboy]

Can you just cast them to text and order that way?

[blm768]

In principle, yes. But that's a far slower operation than directly comparing the numeric data. Since the default ordering comparison is used for performance-critical operations like index lookups, it seems like it should be as fast as reasonably possible.

Given that the layout of ShortPhoneNumber may have to change in order to handle #5 (and the limitation of 15 digits for the national number, which apparently isn't high enough in some rare cases), I may end up resolving this by using a less dense digit-oriented encoding, which would largely solve the collation issue.