Re: Re: PostgreSQL needs percentage function

2017-12-18 17:13 GMT+01:00 Nick Dro <postgresql(at)walla(dot)co(dot)il>:

>
> Hi,
> I know how to implement this. It's not the issue.
> It's very easy to implement absolute value as well yet still PostgreSQL
> gives abs(x) function which is build in function.
> My claim is that if there is a build in function for absolute value why
> not for percentage? Both are very basic mathematical operations.
>
> Can you give a good reason why absolute value has a build in function
> while percentage is not?
>

probably history

abs is some basic functions - the implementation is not primitive. Percent
function is maybe in spreadsheets, but I don't remember this function from
any classic language - more it can be simply implemented by numeric
operators.

In this case, I am not a fan of this functions, you can write just 25 *
0.20

Regards

Pavel

>
> ב דצמ׳ 18, 2017 17:44, hubert depesz lubaczewski כתב:
>
> On Mon, Dec 18, 2017 at 02:23:38PM +0200, Nick Dro 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
> What is the problem with using normal multiplication for this?
> depesz
>
>
>