Re: alter table schema, default sequences stay the same

Sim Zacks <sim(at)compulab(dot)co(dot)il> writes:
>> I haven't consumed enough caffeine today to recall the details, but
>> I think you could have ended up with default expressions like the above
>> if the database had been dumped and reloaded from 8.0 or earlier.
>> nextval(regclass) was introduced in 8.1 precisely to solve this type
>> of problem.

> My first database was an 8.0 and at some point we upgraded to 8.2 so
> that must have caused the ?corruption?

Yeah, that would fit. The upgrade process was intentionally designed to
work that way, because the pre-8.1 behavior of DEFAULT nextval('foo')
was that it always referred to the sequence currently named foo, because
'foo' was just a text constant. We didn't want to risk breaking things
for anyone who was depending on that behavior. But now you have to
explicitly put in ::text if that's how you want it to behave ---
otherwise you get a regclass constant, which will track the original
sequence's identity despite renamings.

regards, tom lane