Re: Error-safe user functions

On 2022-12-05 Mo 20:06, Tom Lane wrote:
> Andres Freund <andres(at)anarazel(dot)de> writes:
>
>> But perhaps it's even worth having such a function properly exposed:
>> It's not at all rare to parse text data during ETL and quite often
>> erroring out fatally is undesirable. As savepoints are undesirable
>> overhead-wise, there's a lot of SQL out there that tries to do a
>> pre-check about whether some text could be cast to some other data
>> type. A function that'd try to cast input to a certain type without
>> erroring out hard would be quite useful for that.
> Corey and Vik are already talking about a non-error CAST variant.

/metoo! :-)

> Maybe we should leave this in abeyance until something shows up
> for that? Otherwise we'll be making a nonstandard API for what
> will probably ultimately be SQL-spec functionality. I don't mind
> that as regression-test infrastructure, but I'm a bit less excited
> about exposing it as a user feature.
>

I think a functional mechanism could be very useful. Who knows when the
standard might specify something in this area?

cheers

andrew

--

Andrew Dunstan
EDB: https://www.enterprisedb.com