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I made some holes (difference) in a shapefile with Q-GIS 2.2.0, than I imported the shapefile in ArcGIS 10.0 and I exported the shapefile to a feature class in a File Geodatabase.

In the feature class the "shape area" doesn't show the right value. I added a new field and I used "calculate geometry". ArcGIS calculated the right surface and it is different from the old one in "shape area".

Why ArcGIS 10 is not updating the value?

Is there a way to recalculate or edit the standard field "shape area"?

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    I think you may be failing to distinguish the difference between an attribute column with "area" in its name and a geometry property. Only the geometry property will be dynamically updated. It also doesn't seem fair to blame ArcGIS for not automatically changing a field in a shapefile edited by QGIS. – Vince Sep 3 '14 at 11:19
  • If the geometric property is dynamically updated, why it is not updated after I had exported the shape file to a geodatabase feature class? The shape area field cannot be touched, as far as I know... – Carlo Pozza Sep 3 '14 at 11:56
  • Geometric properties are ALWAYS updated, field values must be explicitly changed. Look at the shapefile dBase component (.dbf) with Excel or OpenOffice Calc... It shows a "SHAPE_AREA" column, right? What happens if you convert the shapefile to FGDB with "Export... to Geodatabase (single)" and you remove the SHAPE_AREA column? What does the column list look like now? – Vince Sep 3 '14 at 12:33
  • I think the problem is that when I export the file to a feature class in FGB, ArcGIS recognizes the column "shape file" just half: is not possible to update the coloumn but ArcGIS won't recalculate the surface. If I merge/union that feature class with another feature class then the "shape area" became correct. Thank you for your Help! – Carlo Pozza Sep 3 '14 at 14:30
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Quick background (for those who are not familiar with this):
- shapefiles do not allow automatic udpating of area fields
- geodatabase feature classes automatically update areas (or lengths, etc.) when a feature's geometry is edited

So far so good. Now the question is why the area field you defined in QGIS is not updated after your shapefile has been loaded into a Geodatabase in ArcGIS.

This has to do with the fact that ArcGIS does not know it is an area field. To ArcGIS this seems like a normal float field (or maybe even string? Could be, check it out.), but it does not know that the numbers are the result of geometric calculations.

Would you have created your shapefile in ArcGIS, and used Esri's area function, then ArcGIS would know it is looking at an area field and update it accordingly.

Therefore, I suggest you go ahead on your imported files, calculate the area in ArcGIS once, and from then one the problem should be solved. After each edit the area should be updated now.

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ArcGIS is updating the shape_area field in geodatabase feature class, but not in shapefile. If your shape_area field comes from a shapefile, you will have a "normal" field called shape_area in your geodatabase, and this field will not be updated.

  • Yes, I'm talking about a feature class not a shape file – Carlo Pozza Sep 3 '14 at 8:31
  • So you have a feature class in a geodatabase, (note that shapefile also stores feature classes) and the shape_area field does not update. Can you specify exactly which version of ArcGIS you use and what type of geodatabase is problematic? Did you close your edit session ? – radouxju Sep 3 '14 at 8:36
  • Ok, the whole story: I made some holes (difference) in a shape file with Q-GIS 2.2.0, than I imported the shape file in ArcGIS 10.0 and I exported the shape file to a feature class in a File Geodatabase. (as a Answer to your question: I haven't even opened the edit session in Arc GIS). – Carlo Pozza Sep 3 '14 at 8:43
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    Please update the question to include the "whole story". – Vince Sep 3 '14 at 11:04
  • Does the feature class have a projection definition? – johns Sep 3 '14 at 12:46

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