SQL Server, division returns zero

Question

Here is the code I'm using in the example:

 PRINT @set1  PRINT @set2   SET @weight= @set1 / @set2;  PRINT @weight 

Here is the result:

47 638 0 

I would like to know why it's returning 0 instead of 0,073667712

Answer 1

Either declare set1 and set2 as floats instead of integers or cast them to floats as part of the calculation:

SET @weight= CAST(@set1 AS float) / CAST(@set2 AS float); 

Answer 2

When you use only integers in a division, you will get integer division. When you use (at least one) double or float, you will get floating point division (and the answer you want to get).

So you can

1. declare one or both of the variables as float/double
2. cast one or both of the variables to float/double.

Do not just cast the result of the integer division to double: the division was already performed as integer division, so the numbers behind the decimal are already lost.