To set a column to a constant value, use
CONSTANT followed by a value:
CONSTANT data is interpreted by SQL*Loader as character input. It is converted, as necessary, to the database column type.
You may enclose the value within quotation marks, and you must do so if it contains whitespace or reserved words. Be sure to specify a legal value for the target column. If the value is bad, then every record is rejected.
Numeric values larger than 2^32 - 1 (4,294,967,295) must be enclosed in quotation marks.