Compare values in column and change to match others if they don't already

[C_Sharma]

So I have two columns I'm trying to look at. in one there's a description in the other there's an ID number. I want to have it so that whenever an item has the same description they should have the same ID number and if the ID number is blank then it should change to match one that already exists.

Description	ID Number
Test 1	1
Test 2	2
Test 1	1
Test 1

as shown above you have the different descriptions and ID numbers attached. I need to compare the values in the description, see if they match, and if they do match then make sure it has the same value in the ID number. If the ID number is blank, then it should change the blank cell to be the same number for one of the filled ones. I also need to make sure that it's basing the number off of previously filled cells and not a set value as there is no feasible way to have a set number for each of descriptions.

Any help is appreciated! thank you!

[OllieClarke]

Hi @C_Sharma I think it would be much easier for people to help you if you included a starting data set, and a desired outcome data set. 

[chuckleswk]

You could use something like the attached workflow.

First you would assign a RecordID to each entry and then select the first instance of the description. You could then use a Find and Replace to set the corrected / missing ID Number and union those back together.