If you want one: create or replace percent(numeric, numeric) returns numeric language sql as $$ select ($1 / 100) * $2; $$;
On Tue, Dec 19, 2017 at 4:51 PM, Melvin Davidson <melvin6...@gmail.com> wrote: > > > On Tue, Dec 19, 2017 at 4:54 AM, Pavel Stehule <pavel.steh...@gmail.com> > wrote: > >> >> >> 2017-12-19 10:13 GMT+01:00 Nick Dro <postgre...@walla.co.il>: >> >>> This is exactly why I think there should be some build-in function for >>> that... >>> Percentage calculation exists in almost any databse and information >>> system - it requires from use to implement many functions on thier own for >>> something that is very basic. >>> The general idea of my request is that postgresql should have build in >>> function for percentage calculation it doesn't have to me the exact example >>> I gave. Any thing will be better than none. >>> >> >> I don't agree - there is not compatibility or portability reasons. The >> calculation using numeric operators is pretty simple, and possibility to >> create own function is here too. >> >> So there is not any reason to increase a postgresql catalogue. >> >> Please. don't do top post >> >> Regards >> >> Pavel >> >> >>> >>> >>> >>> ב דצמ׳ 18, 2017 18:28, Michael Nolan כתב: >>> >>> >>> >>> On Mon, Dec 18, 2017 at 6:23 AM, Nick Dro <postgre...@walla.co.il > >>> wrote: >>> >>> Hi, >>> Why PostgreSQL doesn't have build-in function to calculate percentage? >>> somthing like percent(number,% >>> for example: >>> select percent(100,1) will calculate 1% of 100 = 1 >>> select percent(25,20) will calculate 20% of 25 = 5 >>> >>> Seems like a nice addition to the math functions list: >>> https://www.postgresql.org/docs/9.5/static/functions-math.html >>> >>> This is veryhelpull function, many uses percentage calculation in thier >>> work and it will simplify the process. Percentage calculation is considered >>> a basic math operation and I think postgresql should support it as a >>> build-in function. >>> Seems like easy to implment isn't it? >>> >>> >>> It's a bit trickier than that, because you';ll have to deal with >>> integers, real, double precision, etc. You may also want to deal with null >>> values. I found it more useful to write a function that displays X as a >>> percentage of Y, rounded to 1 digit to the right of the decimal point. >>> -- >>> Mike Nolan >>> >>> >> > >Percentage calculation exists in almost any databse and information > system > > That is not exactly true. AFAIK, only Oracle has a Percentage function. > SQL Server and MySQL do not. > It has already been shown that it is just as easy to code percentage > inline (EG: SELECT (50.8 x 5.2) / 100 AS pct; ## .026416 > as it is to call a function SELECT pct(50.8, 5.2); > Please do not false statements to justify a request for a non-needed > enhancement. > > > > -- > *Melvin Davidson* > I reserve the right to fantasize. Whether or not you > wish to share my fantasy is entirely up to you. > -- Best Wishes, Chris Travers Efficito: Hosted Accounting and ERP. Robust and Flexible. No vendor lock-in. http://www.efficito.com/learn_more
