Re: Range Types - typo + NULL string constructor

Jeff Davis <pgsql(at)j-davis(dot)com> writes:
> On Mon, 2011-10-10 at 14:27 +0100, Thom Brown wrote:
>> I don't know if this has already been discussed, but can you explain
>> the following:
>>
>> postgres=# select '[1,8]'::int4range;
>> int4range
>> -----------
>> [1,9)
>> (1 row)
>>
>> It seems unintuitive to represent a discrete range using an exclusive
>> upper bound. While I agree that the value itself is correct, it's
>> representation looks odd. Is it necessary?

> The "canonicalize" function (specified at type creation time) allows you
> to specify the canonical output representation. So, I can change the
> canonical form for discrete ranges to use '[]' notation if we think
> that's more expected.

What if I write '[1,INT_MAX]'::int4range? The open-parenthesis form will
fail with an integer overflow. I suppose you could canonicalize it to
an unbounded range, but that seems unnecessarily surprising.

regards, tom lane