php - How can I recursively search through a database? -

i have mysql table 3 columns *id, item_id, dependency*

i want know best way recursively check through dependencies example checking item_id 3's dependencies , requires item_id 2 need check dependencies item_id 2

what best way achieve php?

id | item_id | dependency | ---+---------+------------+ 1  | 3       | 2          | ---+---------+------------+ 2  | 2       | 4          | ---+---------+------------+ 3  | 2       | 5          | ---+---------+------------+ 

pseudo code:

func myquery(item_id) {     query (item_id)     if (!item_id.dependency())      else (myquery(item_id.dependency()) } 

this continue down column until reach item not have dependency.

summary of process: pass first item function. check if has dependency, if does, call function again dependency. otherwise nothing , function return. of course you'll want save items returned query i'll leave you. want statement @ end of function when said , done have data ordered no dependencies dependencies.