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I have two polygons, a red one and a green one. These polygons overlap.

I would like to merge these two polygons. But when I merge them, I would like the attributes of the area where they overlap to be assigned the red polygon’s attributes, not the green polygon’s attributes. I do not want the area where they overlap to be assigned both polygon’s attributes.

i.e. When merging, I would like to assign a higher ranking to the red polygon.

I'm using ArcView 10.0

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Have you looked into the Detect Graphic Conflict Tool in the toolbox under Graphic Conflict?

You could use that tool to find the graphically (make sure outlines are 0 width) overlapping areas. The newly created shapefile's attribute table is populated with the FID from both overlapping polygons. You could join your data using the FID field then create a new field and calculate the rankings. You can only use this tool with two shapefiles at once, so you will need to repeat the process. Once finished, you could merge all the original shapefiles together and merge all the overlapping areas shapefiles together, then erase the merged overlapping areas (Advanced License Level - If you don't have an advanced license then try Xtools for free) from the merged original shapefile. Then merge everything back together again.

Example: I have two shapefiles (Federal Forest and State Forest). I want to symbolize them three ways Federal, State, or Federal and State (overlapping) and I don't want to have to mess around with transparences or drawing order.

Before

  1. Toolbox > Graphic Conflict > Detect Graphic Conflict Output

  2. Join Federal Forests and State Forests using FID fields to the Detect Graphic Conflict Output. Created two new fields (State Forest Name and Federal Forest Name) and used Field calculator to populate the new fields with the Forest Name.

Join Example

Attribute Table Example

  1. Merge State and Federal Forests shapefiles

MergeMerge Example

  1. Erase Overlapping Areas (Analysis Tools > Overlay > Erase)

Input: Merged State and Federal Forests Output

Erase Features: Detect Graphic Conflict Output Erase Tool

  1. Merge the Erase Output with the State and Federal Merge Output. Make sure to clean up the attribute table and make sure all the fields are calculated in the final output.Final Output
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So you have 2 files? In that case you need to merge 2 times, first merge with the Merge (Data Managment) tool, once the polygons are merged in one file start editing the layer and select both polygons and use the merge in the editor tool bar when a window pop up select the polygon from wich you want to keep the atrributes (as in the answer that solmeone alredy gave you)

  • The challenge I have is that I am working with a huge dataset. I am working on a conservation plan. Areas that are closest to Highways are more highly impacted than areas that are closer to secondary roads and so on, with areas inaccessible by any form of road being the least impacted. Using various road classifications and buffer distances, I have created eleven shapefiles, each with a score from 10 to 0. 10 = within 90m of highway. 0 = beyond 3000m from a tertiary road. I need to merge these, and ensure that an area that has a higher score takes preference to an area that has a lower score. – Thomas King Aug 2 '16 at 10:49

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