Sounds as though you should use worksheet 2 as your 'master,' and copy into
it all the rows in worksheet 1 that are missing from 2. To determine which
ones to copy, insert a new helper col in worksheet1 next to the CaseID
column. In the new column, use a COUNTIF() formula to determine if the
CaseID is in the Master sheet. Assuming the helper column is col A, the case
IDs are in col B on wrksheet 1 and col A on wrksheet 2, use this formula in
cell A2:

=COUNTIF(Worksheet2_Name!A:A,B2)

Copy that formula down to the end of your data, then sort on col A.
Anything with a formula result of 0 is missing from worksheet 2. Copy all
those rows and paste them into worksheet 2



"Lori" wrote:

> I have a question I am hoping someone can help me with. I have 2 worksheets
> that I need to merge the data. Both have a common field that I key on, Case
> ID. If the Case ID is found in both worksheets, the data will be pulled from
> worksheet 2. If the Case ID is exists in worksheet 1 but not 2, the data is
> pulled from worksheet 1. If the Case ID exists in worksheet 2 but not 1, the
> data is pulled from worksheet 2.
> Basically, I am exporting data from a system that only gives me current
> data. That file may contain existing cases or new cases that the old file
> does not. The old file may contain older cases that the new file does not.
> I need to retain the old, update the existing and add the new.
> Thanks for the help!