I want to expand/explode an employee table to show all the employees a
boss is responsible for (including him/herself). Then I can say SELECT
Emp FROM Employee WHERE Boss = 'Jane'. It should return Jane, Jill,
and Sally.
Or if anyone knows how to convert this to a nested set hierarchy then
that would be helpful too. I figure exploding the table would be
easier for a newbie like me. Apparently it's not that easy. Thanks...

Explode this table:

Emp Boss
John John
Tom John
Jane John
Jill Jane
Ed Tom
Sally Jill

To this table:

Emp Boss
John John
Tom John
Jane John
Jill John
Ed John
Sally John
Jane Jane
Jill Jane
Sally Jane
Tom Tom
Ed Tom
Sally Jill
Sally Sally

I have this so far. Not sure if it's the right approach. Doesn't
work. It just loops forever:

CREATE PROCEDURE expand_table()
BEGIN
DECLARE sEmp VARCHAR(10);
DECLARE sBoss VARCHAR(10);
DECLARE done INT DEFAULT 0;
DECLARE csrEmp CURSOR FOR SELECT Emp FROM Employee;
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET done = 1;

TRUNCATE TABLE ExpEmp;
OPEN csrEmp;
REPEAT
FETCH csrEmp INTO sEmp;
IF NOT done THEN
SET sBoss = (SELECT Boss FROM Employee WHERE Emp = sEmp);
WHILE sEmp != sBoss DO
INSERT INTO ExpEmp VALUES (sEmp, sBoss);
SET sBoss = (SELECT Boss FROM Employee WHERE Emp = sBoss);
END WHILE;
END IF;
UNTIL done END REPEAT;

CLOSE csrCntr;

END$$