What is the difference between MOD and REMAINDER in oracle?

Question

Although both the functions perform the same operation, even they produce same o/p, what is basic difference between these two? Is there any performance related difference, if yes, then which one is better?

Thanks

Answer 1

The difference between MOD and REMAINDER function can be understood in the example below:

MOD(13,5): returns 3 whereas, REMAINDER (13,5) returns -2

A simple way to understand the difference is that MOD uses the floor function therefore it counts the occurrence of the second number within the first and returns what is left to complete the first number i.e. 2(5) gives 10 adding 3 gives 13 therefore MOD(13,5)=3

However, the REMAINDER uses a Round function it therefore gets the total number of the second number that could make up the first and then subtract the what makes it excess. i.e. 3(5) = 15 and subtracting 2 gives 13,therefore REMAINDER(13,5)= -2

REMAINDER (-15, 4): 4(-4) gives -16 and adding +1 gives -15 hence REMAINDER (-15,4)=+1

MOD (-15, 4): 3(-4) gives -12, adding -3 gives us -15 hence MOD(15,4)=-3