Magnus Hagander <magnus@hagander.net> writes:
>> So even if people don't believe in the rationale behind the patch,
>> would allowing it harm anything at this point?
> Adding it for the sake of upgrades seems very far fetched.
> Adding it for the sake of giving a better error message seems like a
> very good idea. But in that case, the client side code to actually
> give a better error message should be included from the start, IMHO.
What's not apparent to me is how we'll even get to this check; if
there's a mismatch, won't the database system identifier comparison
fail first in most scenarios?
I'm also wondering why send WAL version number and not, say, catalog
version number, if there's some idea that we need more tests than the
system identifier comparison.
Given reasonable answers to these questions, I'd not object to putting
in additional error testing. I concur with Magnus that the patch should
actually provide those tests, and not just put in an unused field.
regards, tom lane