The result type is the same data type as that of the numeric input argument.
If the input argument is defined as a DECIMAL/NUMERIC with a precision less than 38, the precision of the returned DECIMAL/NUMERIC value increases by 1. For example, DECIMAL(6,4) returns as a DECIMAL(7,4). If the precision is 38, the scale is reduced by 1 unless the scale is 0. For example, the return data type for DECIMAL(38,38) is DECIMAL(38,37).
The default title for FLOOR is FLOOR(arg).
For information on default data type formats, see Data Type Formats and Format Phrases.