Mathematical Functions (Transact-SQL)
The following scalar functions perform a calculation, usually based on input values that are provided as arguments, and return a numeric value:
Arithmetic functions, such as ABS, CEILING, DEGREES, FLOOR, POWER, RADIANS, and SIGN, return a value having the same data type as the input value. Trigonometric and other functions, including EXP, LOG, LOG10, SQUARE, and SQRT, cast their input values to float and return a float value.
All mathematical functions, except for RAND, are deterministic functions. This means they return the same results each time they are called with a specific set of input values. RAND is deterministic only when a seed parameter is specified. For more information about function determinism, see Deterministic and Nondeterministic Functions.