Re: What happened to the is_ family of functions proposal?

On 20 September 2010 16:54, Andrew Dunstan <andrew@dunslane.net> wrote:
>
>
> On 09/20/2010 10:29 AM, Colin 't Hart wrote:
>>
>> Hi,
>>
>> Back in 2002 these were proposed, what happened to them?
>>
>> http://archives.postgresql.org/pgsql-sql/2002-09/msg00406.php
>
>
> 2002 is a looooooooong time ago.

<snip>

> I think to_date is the wrong gadget to use here. You should probably be using the date input routine and trapping any
dataexception. e.g.: 
>
>    test_date := date_in(textout(some_text));
>
> In plpgsql you'd put that inside a begin/exception/end block that traps SQLSTATE '22000' which is the class covering
dataexceptions. 

So it's not possible using pure SQL unless one writes a function?

Are the is_<type> family of functions still desired?

Also, where are the to_<type> conversions done?

Thanks,

Colin