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Using JMP > Reshape Your Data > Virtually Join Data Tables > Example of a Link ID and a Link Reference on a Single Column
Publication date: 11/10/2021

Example of a Link ID and a Link Reference on a Single Column

Suppose that employee data is available in multiple data tables and can be linked together by a single column that has both a Link ID and a Link Reference property. To see an example of how the data tables are set up, follow these steps:

1. Select Help > Sample Data Library and open Employee Master.jmp.

Note: In the Employee Id column’s Link Reference column property, the Auto Open option is selected to automatically open two other tables, Education History.jmp and Predicted Termination.jmp. They appear in the Home Window’s Window List.

Employee Master.jmp has information about each employee.

Education History.jmp has the information about the education of each employee.

Predicted Termination.jmp has job performance information about each employee.

2. Open Predicted Termination.jmp from the Home Window’s Window List.

Notice that the Employee Id column has a Link ID column property.

Figure 6.44 Link ID Column Property 

Link ID Column Property

3. In Employee Master.jmp, select the Employee Id column and select Columns > Column Info.

Figure 6.45 Link ID and Link Reference Column Properties in Employee Master.jmp 

Link ID and Link Reference Column Properties in Employee Master.jmp

Notice that the column has a Link ID column property and a Link Reference to Education History.jmp.

In the data table’s Columns list, the Link Reference icon Image shown here and Link ID icon Image shown here appear next to the Employee Id column.

4. Open Education History.jmp from the Home Window’s Window List.

5. Select the Employee Id column and select Columns > Column Info.

Figure 6.46 Link ID and Link Reference Column Properties in Education History.jmp 

Link ID and Link Reference Column Properties in Education History.jmp

As shown in Figure 6.46, Employee Id has a Link ID column property and a Link Reference to Predicted Termination.jmp.

Figure 6.47 Linked Data Tables 

Linked Data Tables

The Employee Id column of Employee Master.jmp references Education History.jmp, which then references Predicted Termination.jmp. All data are available through virtual join from the main data table, Employee Master.jmp.

Notes:

Auto Open in a column’s Link Reference property specifies whether the linked table is automatically opened when the main data table is opened.

If referenced columns are unhidden when the data table is saved, those referenced columns are automatically linked and unhidden when the table is opened.

When you close the data tables, it is a best practice to close the main table first (Employee Master.jmp), because there is a link between that table and all the others. Closing them in a different order might display a prompt indicating that the table that you are closing has other windows open. You might want to cancel and consider saving and closing your tables in a different order.

Want more information? Have questions? Get answers in the JMP User Community (community.jmp.com).