Re: 4.1beta1: ANYARRAY disallowed for DOMAIN types which happen to be arrays

On Tue, May 10, 2011 at 1:52 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Mon, May 9, 2011 at 11:32 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> So we basically had three alternatives to make it better:
>>>        * downcast to the array type, which would possibly silently
>>>          break applications that were relying on the function result
>>>          being considered of the domain type
>>>        * re-apply domain checks on the function result, which would be
>>>          a performance hit and possibly again result in unobvious
>>>          breakage
>>>        * explicitly break it by throwing a parse error until you
>>>          downcast (and then upcast the function result if you want)
>>> I realize that #3 is a bit unpleasant, but are either of the other two
>>> better?  At least #3 shows you where you need to check for problems.
>
>> Aren't any applications that would be broken by #1 broken already?
>
> My point is that doing #1 would break them *silently* --- if you did
> have a problem, figuring out what it was could require a great deal
> of sleuthing.

Eh, I'm confused.  Explain further?

--
Robert Haas
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