function SET_FLAG_VALUE_BG(var iFlags: Int64; var iBitIndex: SmallInt; var iBitValue:SmallInt): Int64; cdecl; export;
begin
     if iBitValue>0
      then Result:=iFlags or (1 shl iBitIndex)
      else Result:=iFlags and Not (1 shl iBitIndex);
end;

CREATE FUNCTION SET_FLAG_VALUE_BG (
    AFLAG BIGINT,
    ABITINDEX SMALLINT,
    ABITVALUE SMALLINT)
RETURNS BIGINT
AS
BEGIN
  / Function Text /
  IF (:ABITVALUE > 0) THEN
    RETURN BIN_OR(:AFLAG, BIN_SHL(1, :ABITINDEX));
  ELSE
    RETURN BIN_AND(:AFLAG, NOT BIN_SHL(1, :ABITINDEX));
END