So glad you found it helpful and informative

Glad you liked it.

You cannot do a join with a one to many relationship. You can use a relate in a one to many or many to many relationship. If your data is in a geodatabase you can also create a relationship class to link the data. All of these options keep the data in separate tables but does link records together based on the key fields. If your data is in something like SQL Server, PostgreSQL, or Oracle, you might also be able to create a view that combines the two tables together.

Thank you

Will do. I believe it was 2.6 at the time of the video.

Without seeing the data it is hard to say exactly. It could be a problem with the data values. For example you might have unseen leading or ending spaces in the values. This often happens when you try to use text fields as the key fields for the joins or relates.

Glad you thought the video provided a clear explanation. To answer your question, in a best-case scenario the non-spatial or stand-alone table would be included in a geodatabase. If that is not possible then any format supported by ArcGIS Pro including DBF, CSV, or any relational database (SQL, PostgreSQL, Oracle, or similar) you have can connect to. I would avoid Excel files if possible. Technically they will work but ArcGIS is very picky about working with Excel files. They have to be formatted very simply and meet specific standards. Also, Microsoft Access should be avoided. For a long time, ArcGIS Pro did not support Access at all. I believe with the newest versions of Pro you can connect to an Access database but it is still a bit unstable.

@@eGISAssociates Thank you kindly

Data connected via a relate or a relationship class cannot be used to symbolize or label features in a map. Relates or relationship classes are required if you have a one-to-many or a many-to-many relationship.

First thing I would do is convert the spreadsheet to a DBF file since you are working with shapefiles. ArcGIS will read a spreadsheet but will often have issues unless it is a very simple spreadsheet that also conforms to Database standards. Next verify the the field type (Text/String, Integer, Float, Double and so on) for the ALTKEY field in both tables match. You cannot join or relate if they don't. Next you need to determine how many records in your shapefile match to records in your converted DBF. I mean does each parcel only have up to one matching record in the DBF or does it have multiple matches in the DBF or does each record in the DBF match to multiple records in the parcel shape file. If each parcel matches to no more than 1 record or row in the DBF or if a single record/row in the DBF matches multiple parcels in the shapefile, then you can do a join. Otherwise you would need to do a relate. Hopefully this helps even though it is a bit late.

Thank you so much for the very kind words. They are appreciated. I will see what I can do to provide an explanation. Italy is a beautiful Country. I enjoyed visiting Naples and Trieste back in the 90s.

Not sure if that was a question or a statement but yes more than one can be joined.

@@67Stang was a question. Thanks!