> -----Original Message----- > From: Andrew Dunstan <andrew@xxxxxxxxxxxx> > Sent: Wednesday, September 8, 2021 13:31 > To: ldh@xxxxxxxxxxxxxxxxxx; pgsql-performance@xxxxxxxxxxxxxx > Subject: Re: Better performance no-throw conversion? > > > On 9/8/21 1:17 PM, ldh@xxxxxxxxxxxxxxxxxx wrote: > > > > Hello, > > > > > > > > Some databases such as SQLServer (try_cast) or BigQuery (safe.cast) > > offer not-throw conversion. In general, these tend to perform better > > than custom UDFs that catch exceptions and are also simpler to use. > > For example, in Postgres, I have a function that does the following: > > > > > > > > CREATE OR REPLACE FUNCTION toFloat(str varchar, val real) > > > > RETURNS real AS $$ > > > > BEGIN > > > > RETURN case when str is null then val else str::real end; > > > > EXCEPTION WHEN OTHERS THEN > > > > RETURN val; > > > > END; > > > > $$ LANGUAGE plpgsql COST 1 IMMUTABLE; > > > > > > > > I couldn't find a reference to such capabilities in Postgres and > > wondered if I missed it, and if not, is there any plan to add such a > > feature? > > > > > > > > > Not that I know of, but you could probably do this fairly simply in C. > > > cheers > > > andrew > > -- > Andrew Dunstan > EDB: https://www.enterprisedb.com Hello Andrew, I work across multiple platforms (windows, linux, multiple managed cloud versions...) and a C-based solution would be problematic for us. Thank you, Laurent.
