GetHierarchy

Greetings !

I have a hierarchy table with two attributes :  Parent_ID, Child_ID with the sample data (can go upto n-level) as below:


 
 
  ParentID
  ChildID
 
 
  1
  3
 
 
  1
  4
 
 
  3
  5
 
 
  5
  6
 
 
  6
  7
 


I need a query to retrieve all the n level hierarchy when a Child node_id is passed. For example; if I pass 7, then i need parent nodes as below: I want to achive this in postgres database (version 9.2) without connect by prior.

3   5
5   6
6  7

Any reply on this is great help.

Thanks and REgards
RAdha Krishna