Definition: The Oracle BINARY_INTEGER is defined in the STANDARD package as a subtype of INTEGER. Variables declared as BINARY_INTEGER can be assigned values between -2,147,483,647 to 2,147,483,647.
Prior to Oracle9i R2, BINARY_INTEGER was the only indexing datatype allowed for associative arrays. As per Oracle's documentation, the BINARY_INTEGER datatype is identical to PLS_INTEGER.