Parent/Child Field

[turtle]

This should be a pretty basic question.

I need to fill in the child field with the parent field of a WBS
structure. Let me give an example

V/XXX3.CHA.07 4 V/XXX3.CHA.07.02
V/XXX3.CHA.07.02 5 V/XXX3.CHA.07.02.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.03
V/XXX3.CHA.07.03 5 V/XXX3.CHA.07.03.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.04
5 V/XXX3.CHA.07.04.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.05
5 V/XXX3.CHA.07.05.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.06
5 V/XXX3.CHA.07.06.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.07

 

[turtle]

This should be a pretty basic question.

I need to fill in the child field with the parent field of a WBS
structure. Let me give an example
Parent ID Lev
V/XXX3.CHA.07 4 V/XXX3.CHA.07.02
V/XXX3.CHA.07.02 5 V/XXX3.CHA.07.02.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.03
V/XXX3.CHA.07.03 5 V/XXX3.CHA.07.03.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.04
5 V/XXX3.CHA.07.04.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.05
5 V/XXX3.CHA.07.05.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.06
5 V/XXX3.CHA.07.06.01
V/XXX3.CHA.07 4 V/XXX3.CHA.07.07

Sorry, i didn't finish my explanation. In the first column where
there are blanks i want it to look at the 3rd column to get the parent
id. If the level is 5 and the 1st field is bland then i want it to
look for the last 4 and put in that parent. I suck at explaining
things obviously so if you have questions let me know.
thanks,
KO