Re: Custom ordering operator for type xid

Alexander Lipatov <lipatov(at)mindbox(dot)cloud> writes:
> **Question**: Is it safe to create custom ordering operators for the `xid` type and a default operator class with these operators?

I wouldn't do it, mainly because the semantics of what you've written
have nothing to do with the actual behavior of xids. (The real
comparison behavior is "circular", which can't be modeled as a total
order, which is why there's not a built-in opclass already.)

What is that ORM doing with XIDs anyway, and is there a good reason
not to run away screaming from such an ill-thought-out product?
I don't believe for a minute that this is going to be the only
semantic issue you'll run into with an ORM that thinks it knows
how XIDs behave despite a clear lack of even the most minimal
investigation into the question.

regards, tom lane