compare and align data

Hello,

I have two data sets on one worksheet with lists of data from different soruces EG:


DATA 1 DATA 2
code : key : qty code : key : qty
1 a 6 1 a 6
2 b 6 3 c 10
3 c 10 4 d 8
ect

Would like:

DATA 1 DATA 2
code : key : qty code : key : qty
1 a 6 1 a 6
2 b 6
3 c 10 3 c 10
4 d 8 4 d 8
ect



I want to match the two lists by key and compare the asociated QTY. To do this manualy I am having to go through the list and see where they stop matching up and insert cells to make them match again. There is over 10000 lines so this will take ages. IS there a method or script that will comparte and align the rows?

Any help much apreciated.

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