How to do it...

1. To begin, you will need to start ArcGIS Pro.
2. In the ArcGIS Pro start window, click on Open another project.
3. Select Computer from the Open window and then click Browse in the area on the right:

1. Navigate to C:\Student\ArcGISProCookbook\Chapter3\Joining Data by clicking on C:\ in the area on the left of the Open Project window. Then double-click on Student, ArcGISProCookbook, Chapter3, and Joining Data folders.
2. Select the Joining Data.aprx project file and click OK.

The project will open with a single map named City of Thomasville. The map contains two layers, City Limits and Parcels, plus the Topographic basemap. First you will review the information contained in the Attribute Table for the Parcel layer.  

1. In the Contents pane, right click on the Parcels layer and select Attribute Table from the menu that appears. The Attribute Table for the Parcels layer should open in a window located at the bottom of the map view.

1. Take a moment to look at the fields the Attribute Table contains, and answer the following question:

As you can see, the table contains information about the parcel, such as the Parcel Identification Number (PIN), RealKey, OwnerKey, and more. It does not, however, contain any information about who owns the parcels. However, you do know that information is available in the Computer Aided Mass Appraisal (CAMA) system located in the Tax Appraisal Office for the County.

They have provided you with a table of all the land owners in the County. You now need to join it to your Parcels layer.

1. In the Catalog pane, normally located on the right side of the interface, expand the Databases folder by clicking on the small arrowhead to the left.
2. Expand the Thomaston.gbd so that you can see its contents. You should see at least three feature classes (CityLimits, Parcels, and Street_CL) and a couple of stand-alone tables (Owners and Parcels_Sales).
3. Right-click on the Owners table and select Add to Current Map.

The newly added table should appear in your Contents pane at the bottom of the list. Now you will look at the data contained within this newly added table.

1. In the Contents pane, right click on the Owner table you just added and select Open. The Owners table should open in the same area as the Parcels Attribute Table.
2. Review the Owners table, paying close attention to what fields it contains. Then answer the following question:

As you can see, this table does have information about all the land owners in the County. However, it does not have any information about the parcels they own. In order to join the Owner information to the Parcels, you must identify a key field. A key field is a field in each table which contains data common to the two tables you are attempting to link. Now you will identify a key field in each table, which you will use to link them together.

1. In the table view area, click on the tab at the top of the table which says Owners. Hold your mouse button down and begin to drag it downward. A series of icons should appear in the middle of the table view. Drag your mouse to the icon which has the filled beige area located on the right side as shown ahead. Then release your mouse:

You should now see the two tables side by side, as shown in the following image. This allows you to see data in both tables at the same time. 

1. In the Parcels table, right click on the Ownerkey field and select Sort Descending.
2. In the Owners table, right click on the OwnKey field and select Sort Descending.
3. Review and compare the values for these fields in each table, then answer the following question:

Now that you have verified the two fields contain like values, you need to verify the field types are the same.

1. Right-click on the OwnerKey field in the Parcels table and select Fields from the menu that appears:

1. Perform the same operation on the OwnKey in the Owners table.

Your table view should now look like this:

1. Verify that the Data Type is the same for the Ownerkey field in the Parcels table and the OwnKey in the Owners table.

As you can see, the fields are both a Double data type. Since the fields contain the same data values and the field types are the same, these fields can be used to link the two tables. Now, it is time to link them.

1. Close the Tables and the Fields tab by clicking on the small X.

1. In the Contents pane, right click on the Parcels layer. Go to Joins and Relates and select Add Join.

The Geoprocessing pane should open with the Add Join tool.

1. Verify that the Layer Name or Table View in the Add Join tool is set to Parcels.
2. For the Input Join Field, select OwnerKey.

1. For the Join Table, select Owners by clicking on the small drop-down arrow in the cell. The Owners table may automatically be populated into the cell. If so, you do not need to change it.
2. Set the Output Join Field to OwnKey using the drop-down arrow if needed. It may be automatically set.
3. Verify that the Add Join tool looks like the following screenshot. If it does, click Run:

1. Close the Geoprocessing pane once the Add Join tool has completed successfully by clicking on the small X in the upper-right corner of the pane.
2. Right-click on the Parcels layer in the Contents pane and select Attribute Table.
3. Using the scroll bar at the bottom of the Parcels table, scroll through the table fields.

As you can see, the fields that were on the Owners table have now been added to the Parcels Attribute Table. Now that those fields have been added, you can use that information to locate all parcels owned by a specific owner, or label parcels with the owner. Let’s put that to the test.  You will start with labeling the parcels with fields from the joined table in the next recipe.

1. Close the Parcels table by clicking on the small X in the tab which shows the table name.
2. Click on the Project tab in the ribbon, and click on Save, located in the panel on the left side.
3. If you are continuing to the next recipe, keep ArcGIS Pro open. If you are not you may close ArcGIS Pro.