I have 2 separate workbooks of data. The "new" one has 1000 rows of data. The "old" one has 750 rows of data. They both have the same exact columns. I need to look at the data in column "C" which is a unique part number. Match the old data with the new data. For example: If row 25 in the old one has part number 123 and row 35 in the new one has part number 123, I need to copy the entire row from the old to the new. I guess I can use a Lookup table, but I'm not sure how to tackle this.
So after matching the old with the new, there will be 250 rows that do not have data.
HELP!
I hope that I'm explaining this so it's understood.
Any help is greatly appreciated

You could possibly use the VLOOKUP function to retrieve your data using column() as argument
So supposing your old data is in range A1:G100 in the new range in B1 enter
=VLOOKUP(A1,wkbk_name_and_sheet!$A$1:$G$100,column (),false) and drag right and down. Adapt to your layout if needed

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I'm sorry, I had the story all wrong. This is the scenario.
I have 2 separate workbooks of data. The "new" one has 1000 rows of data. The "old" one has 750 rows of data. They both have the same exact columns. I need to look at the data in column "C" which is a unique part number. I have to find which 250 records have been added to the “new” and add them to the “old.” So, 250 records will be added to the "old" one and 750 records remain.
Your help is greatly appreciated, Karen

If it is a one time job, paste the "new" range underneath the "old" one
Select the obtained range
Select data - Advanced Filter
Filter In Place
Check Unique records only
OK

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