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I have two shapefiles with some of the parcels (surveying) overlapping each other. How do you get those overlapping parcels from doubling up? Is there a way you can have it dissolved or union etc... so that second parcel with the same "tax id number" from being included in the merge?

Thank You.

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The answer really depends on the condition of your two data sets. Is one more accurate than the other? Are the overlaps of identical features, or do the parcels only partially overlap each other? How many overlaps are there? A couple? Dozens? Hundreds? A liitle more info, or a screen shot if possible, would help. – Don Meltz Oct 24 '10 at 20:06
up vote 6 down vote accepted

Like Don hinted above, it depends on the relative status of your two feature classes:

  • If one is the reference, then you want to keep all parcels from this layer, and discard the same parcels from the second layer. Join the second parcel with the first one based on the tax id field. Make sure you keep all records (and not only the matching one). You can now list all the records in the second layer, that are not in the reference layer, by their empty attributes, and easily add them to the reference layer.
  • If they are both equally important, merge them and dissolve on the tax id field.

Let me know if I understood your question correctly.

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You stood it correctly, Don. Just the problem is the two parcels, surface and minerals are not identical in size. I was just trying to find various methods in doing it. I appreciate your replies. – Zoran Oct 25 '10 at 19:03

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