Re: More outdated examples

Bruce Momjian <pgman@candle.pha.pa.us> writes:
> I can find no suitable replacement for this example.  Can anyone else?

> Peter Eisentraut wrote:
>> This example in User's Guide section 7.2 doesn't work anymore at all:
>> 
>> tgl=> select @ text '-4.5' as "abs";

Both of the examples in this section have been obsoleted by our recent
elimination of a lot of implicit casts.  This one would still work if
text-to-float8 were an implicit cast, but it's not anymore.  Also,
though the second one still acts as described, the reason given for it
in the text is wrong: the system is not unable to choose among multiple
alternatives.  Rather, it finds *no* alternatives, again because the
text-to-various-int-types casts are no longer implicit.

The closest similar cases that I can find for the first example are not
good replacements because they are also slated for destruction :-(.
Basically, I see us moving away from the preferred-type mechanism, and
perhaps eliminating it entirely soon.

I'd just remove the whole of Example 7.3, I think.  The mechanisms are
still there, for now, but they are not invoked in any standard cases.
        regards, tom lane