SQL - Recursive Heirarchy Trees

Assuming a table something like this:

PERSON_ID
PARENT_ID
NAME

Start with this.

SELECT
LPAD(' ', 2*level-1) || SYS_CONNECT_BY_PATH(NAME, '\') "Path"
FROM TABLE_NAME
CONNECT BY PRIOR PERSON_ID = PARENT_ID;

Google "Connect By" for more information.