Fibonacci procedure for #firebird

I had to do  (recursive function example) Fibonacci stored procedure for Relational Databases exam
so here it is

	SET TERM ^ ;
	CREATE PROCEDURE FIBONACCI (NUM INT)
	RETURNS (N_FIBONACCI DOUBLE PRECISION)
	AS
	DECLARE VARIABLE NUM_LESS_ONE INT;
	DECLARE VARIABLE NUM_LESS_TWO INT;
	DECLARE VARIABLE RESULT1 DOUBLE PRECISION;
	DECLARE VARIABLE RESULT2 DOUBLE PRECISION;
	BEGIN
	IF (NUM = 1) THEN
	BEGIN
	N_FIBONACCI = 1;
	SUSPEND;
	END
	ELSE IF (NUM = 2) THEN
	BEGIN
	N_FIBONACCI = 1;
	SUSPEND;
	END
	ELSE
	BEGIN /**** RECURSION: NUM FIBONACCI = (NUM -1) * (NUM-2) FIBONACCI ****/
	NUM_LESS_ONE = NUM - 1;
	NUM_LESS_TWO = NUM - 2;
	EXECUTE PROCEDURE FIBONACCI NUM_LESS_ONE
	RETURNING_VALUES RESULT1;
	EXECUTE PROCEDURE FIBONACCI NUM_LESS_TWO
	RETURNING_VALUES RESULT2;
	N_FIBONACCI = RESULT1+RESULT2;
	SUSPEND;
	END
	END^
	SET TERM ; ^

view raw Fibonacci for Firebird hosted with ❤ by GitHub

To run it and test the numbers type in flamerobin

SELECT N_FIBONACCI
FROM FIBONACCI ('6')
=8