The FLOOR function returns the largest integer value smaller than a number. If the number is already an integer, it returns the same number as the result. The return data type is the data type of the input parameter.
Below you can see how the FLOOR function behaves at different values.
1 2 3 4 5 | SELECT FLOOR(1), FLOOR(0.34234), FLOOR(-1), FLOOR(0.0), FLOOR(-0.999) |