It looks like they themselves (GNS) don't even do what you're asking, at least going by the default symbology in their public services. They appear to be grouping the values, but using the same field as the data you've got.
I don't know that I'd call it a flaw. There's no way for ArcMap to know that each value in a given field has a corresponding unique value in another field. But there is still a way to do this without manually doing it!
There are a few steps, but I think it'll come out ahead with 51k values!
- Add your layer to a file geodatabase, if you haven't already.
- Summarize the layer
- Use both "plotSymbol" and "name" as your case fields
- The statistics fields aren't important here, just set it to count one of the fields
- The output will be a table with one row for every combination of the two case fields
- Use the table to domain tool
- Use the newly-derived statistics table as your input
- For code field, select "plotSymbol"
- For description field, select "name.
- After running the tool, you'll now have a domain that associates the values in the plotSymbol field (your codes) with the corresponding values in the name field (your descriptions).
- Open the Fields view for the imported polygon layer.
- For the "plotSymbol" field, assign it to the newly created domain
- Values in "plotSymbol" will automatically be associated with their stored descriptions in the domain. Importantly, this includes inserting the description instead of the code on things like legends.
I know that probably seems like a lot, but it should run fairly quickly.
Final note! If you had to import the feature class into a file geodatabase (I don't know what format you got it in, but am assuming SHP?), the newly imported feature class might not have picked up the symbology from the source layer. If that happens, just import it from the other layer.
- Josh Carlson
Kendall County GIS