php - How to turn a mysql table with a simple parent child relationship to a nested set? -

i have large mysql table - altered ldap dump. 120k employees.

the table needed lots of things have 1 task pegging server - recursive queries. each employee has empl. id , supervisor id on row. easy parent child relationship. 1 of applications have mass email app. , use ldap table search employees under given manager. may go 6-10 levels deep , include 10-20k rows. intense. current system not working large queries.

so how can automate parent child relationship nested set? beyond have done in mysql appreciated.

also how has not been asked 100 times?

you may want take @ article:

http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/