How to determine if two sets of polygons are adjacent to each other?

Question

Hi everyone,

I have a geodatabase table containing subject ID, Census Tract ID 1, and Census Tract ID 2. How can I know if the two census tracts are adjacent or not?

For example

subject ID | Tract ID 1 | Tract ID 2

1001 | 48201223100 | 48201250100

How do I find out if 48201223100 and 48201250100 are adjacent or not?

Thanks!

DanPatterson · Answer

Yes... the links I sent you are options.  Have a look at them and decide what is appropriate for your situation.

tutu · Answer

Thank you for your reply!

The table has over 800 records and I need to figure out if the census tracts are adjacent for each subject. It will take a lot of time and energy to go through them manually so I wonder if there is another way.

DanPatterson · Answer

If you want to know all the neighbors for all your polygons, then look at

How Polygon Neighbors Works—ArcGIS Pro | Documentation

you can probably ignore the geometry output stuff since you don't need it.

Alternatives are spatial joins, near as table (using the same file for both inputs)

Generate Near Table (Analysis)—ArcGIS Pro | Documentation

It really depends on what you actually need... assuming that it isn't as simple as finding those two Tract ID s in the table and selecting them and looking at it in the map to see if they are adjacent