Re: Prefered Types

"Greg Sabino Mullane" <greg(at)turnstep(dot)com> writes:
> Tom Lane wrote:
>> BTW, not to rain on the parade or anything, but I'll bet that
>> rejiggering anything at all here will result in whining that puts the
>> 8.3-era removal of a few implicit casts to shame.

> I'll take that bet, as it's really hard to imagine anything being worse
> than the pain caused by 8.3 to many people using Postgres.

You think? At least the 8.3 changes resulted in easily-diagnosed parser
errors. The folks who complained about it were complaining because they
couldn't be bothered to fix anything about their applications, not
because it was difficult to understand or to fix. It seems likely to me
that any changes in function resolution behavior will result in failures
that are *much* harder to diagnose. The actual fix might be the same
(ie, insert an explicit cast or two) but back-tracking from the observed
problem to that fix could be an order of magnitude more difficult. For
example, if you start noticing an occasional integer overflow that
didn't happen before, it might be pretty darn difficult to figure out
that the problem is that an operation that was formerly resolved as int4
+ int4 is now resolved as int2 + int2.

regards, tom lane