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
