For a field with numeric values between -30,000 and 30,000 with no decimals, what is the smallest size data type?

The smallest size data type that can represent numeric values between -30,000 and 30,000 without decimals is Int16.

Int16, or 16-bit integer, can represent values ranging from -32,768 to 32,767. This range comfortably includes all numbers from -30,000 to 30,000, making it the most efficient choice for storing these values in terms of memory usage. As a 16-bit integer, it requires less storage compared to larger types like Int32, which would permit a much broader range of numbers than necessary for this given dataset.

Choosing Float would be unnecessary for this specific scenario as it is typically used for representing decimal values or larger integer ranges, which also requires more memory compared to Int16. The Int8 option is not valid as it can only represent -128 to 127, which is insufficient for the values specified. Therefore, Int16 is the optimal data type for representing the range of numbers in this case while ensuring efficient storage.