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?
Frankly, the name "percent" is a poor choice: am I supposed to input two number and it gives me the percentage that the first is of the second (division) or, at you think here, I input a number and a percentage to multiply them? And why is percent >1 as opposed to (generally) between 0 and 1?
abs(x) has only one input and so none of those questions apply to it.
