My example doesn't deal with a phone/email list, however it very well could be. Specifically I have a county provided list of real estate parcels that include a column for Longitude and a column for Latitude. For example:
A1 (parcel#) - 999999999
B1 (Longitude) --110.036278
C1 (Latitude) 32.149728
The county parcel lists that I'm dealing with sometimes include upwards of 450,000 parcel numbers, so my current process is daunting.
My task is to take a list of foreclosed parcel numbers and use the county provided list as a "KEY" to find the corresponding Longitude and Latitude. It would be quite simple if the foreclosure lists did not repeat, however due to the nature of foreclosures, a piece of real estate can show up five to six times with unique auction dates, but the same parcel #. I do not want to discard the duplicates, because knowing a foreclosed parcel's auction has been rescheduled five times is an importnat piece of information.
My current process is laborious. I sort both columns of parcel numbers by smallest to largest and then with them side by side I can identify duplicates, if there are 5 foreclosed parcel number 999999999's for instance I insert four rows and copy the number, lat, and long columns and paste it after the on instance of the county provided "999999999=lat 32.149728, long -110.036278"
It might be confusing to picture so here is an example:
http://spreadsheets.google.com/pub?key=pmGHBzfUvyOXna8qPmV3SZw
You will notice that there are two blank columns after the foreclosure parcel numbers, that is where I need Latitude/Longitude values provided by the county to be pasted in.
My "Subject Line" of this post is in hopes that someone else has come accross this problem, maybe an address book that list mr smith once, yet a corresponding list that needs Mr Smith's equivalency pasted several times..It might be a bad comparrison, I was hoping that an answer to my post would be an answer to other scenarios as well.