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This may be an easy question so please forgive me if it is (or if it makes no sense) as this is all very new to me.

I have 3 files that I am trying to cross reference. One file has columns category, shape area, and shape length. Another file has category and value. The third has a location id, latitude, and longitude.

Is it possible to match the values to the locations id's? What I can't figure out is if Latitude and Longitude can be cross referenced to Shape Area and Length.

There are gdb files downloaded from FEMA that contain flood zone data. I can open them in QGIS and see the flood zone panels as well as the attribute data that shows the flood zone name. I have a second file in Excel with geocoded addresses. I was hoping to pull the flood zone name for each address into Excel systematically. Is this possible?

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    Welcome to GIS SE. Please edit some extra info into the body of the question for clarification: e.g. are you talking about an Esri shapefile? Also, are the category columns relatable? How else do you expect the files to be cross-referenced?
    – Martin F
    Apr 3, 2015 at 4:01
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    Shape area and length are simply geometric properties of a given shape, so no, they don't really have any relationship to lat and long coordinates. There's not nearly enough information in your question to definitively answer it. You don't mention what format the files are. If category is the same in both of those two, yes you could cross reference those. Area and length indicate a polygon (if it's not just attributes), so your third file being points (coordinate pairs) you could reference those by whether the point falls in the polygon. So what software are you using, and what file formats?
    – Chris W
    Apr 3, 2015 at 20:35

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There's still a bit of missing information, but a general answer would be to:

  1. Add your coordinates in the Excel file as points to the map. You may need to first save as csv format, then use Vector Add Delimited Text and specify the correct columns as lat/long (making sure you also set it to WGS84 or other appropriate CRS for your coordinates, and not letting it default to the project or flood zone CRS which it probably won't match).
  2. Once you've gotten your points in the map along with your flood zones, use a Spatial Query or Intersect operation to get the attributes of the flood zones transferred to the points. Depending on how you do this the result may or may not be a new permanent file (joins usually aren't, intersect would be) and require exporting/saving if you want one.
  3. Finally, since it appears you only care about the tabular results and not the geographic forms, save the resulting table back out to an Excel document if you have that option or a csv to import into Excel if not.

I'm unclear on whether zone name is in a separate table from the shapes; if so you'd need to attribute join the two together (and possibly export to a new file) before the Spatial Query/Intersect.

You can find specific instructions and help on all of these tasks in the QGIS Documentions (link to 2.6 version).

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