xltest,
I realise you probably believe you are being clear, but your situation/explanation(s) still leave me a little confused.
Here is what I think I understand:
1) You are working in Excel (and not MS Access)
2) You have 60K + rows of data on which you want to expediently perform a one-off manipulation.
3) The data of interest/use is in two columns, A & B.
4) Some rows have data in both column A and column B.
5) Some rows have data in column A only (column B is empty).
6) All rows have data in column A.
7) For rows that do have data in column B, you do not want to change any data in that row.
8) For rows that have column B empty you would like to duplicate the value from Column A into column B
9) Column B does not contain any formulas (only values or blank/empty cells).
Are ALL of the above statements correct ? If any is not correct, please advise, which one(s), and what the correction would be.
If they are ALL correct, the following should work:-
A) Pick an empty column. I'll assume you've picked C.
B) In Column C place the following formula
=IF(OR(ISBLANK(B2),TRIM((CLEAN(B2)))=""),A2,B2)
if you were certain that the target cells in B are empty and don't, for example, contain spaces or carriage retruns or other spurious non-printing characters, a slightly simpler formula would work - the above formula caters for the possibility of spaces, carriage returns, etc. being present which may appear like an empty cell, when it is not in fact empty. If such characters might exist and retaining them is desireable, then use the below formula instead.
=IF(ISBLANK(B1),A1,B1)
C) Copy it and paste it down the entire column (using whatever method you find most convenient)
D) Select Column C and Copy it
E) Select column B
F) From the edit menu, use "Paste Special" and choose "Values" to paste the result of the formula into column B.
G) Delete column C
Hope This helps
Regards
John.