Calculate geometry fails for no reason?

[Mikhail]

Hi All, I have an unexpected problem. My shapefile consists of a number of polygons, and I need to know their areas. I select the ID column in the Attribute Table and start Calculate Geometry. It runs but creates no extra columns, so I cannot see where the areas are. In addition, something happens to the ID field, as the IDs change in some random order. I attach screenshots of the Attribute Table before and after running Calculate Geometry. Could someone help?

[alex_mapintel · Accepted solution]

Hi @Mikhail 

I would create a new attribute called 'area_<units>' and set the data type to decimal or integer. Then perform the geometry calculate on the new attribute.

In your example, it looks like you are calculating the area of the polygon into the "ID" attribute. 

[Mikhail]

Hi Alex, thank you very much for your advice! I did not realize that the area goes into the selected field.

[DanPatterson]

There is no need to select the ID field

Calculate Geometry Attributes (Data Management)—ArcGIS Pro | Documentation

specifies the requirements

[Mikhail]

Thanks, now I have better understanding of how this tool works.