Re: Is it time to kill support for very old servers?

I wrote:
> pg_dump alleges support for dumping from servers back to 7.0. Would v10
> be a good time to remove some of that code? It's getting harder and
> harder to even compile those ancient branches, let alone get people to
> test against them (cf. 4806f26f9). My initial thought is to cut support
> for pre-7.3 or maybe pre-7.4 servers, as that would allow removal of
> support for cases where the server lacks schemas or pg_depend, each of
> which requires a fair deal of klugery in pg_dump.

Per subsequent discussion, we should use a round number as the version
cutoff, so attached is a patch that removes pg_dump/pg_dumpall support
for dumping from servers before 8.0. This eliminates circa 1500 lines
of code, or about 4% of the existing code in src/bin/pg_dump/. So it's
not a huge savings, but it eliminates a lot of hard-to-test cases.

I (think I) did not do anything that would damage pg_restore's ability to
read dump archives produced by pre-8.0 versions. I'm pretty hesitant to
remove that code since (a) there's not all that much of it, and (b) it's
easy to imagine scenarios where an old backup dump is all someone's got.
However, that's another set of cases that's darn hard to test, so it's
somewhat questionable whether we may have broken it already.

Comments, objections?

regards, tom lane