We can type anything in the Add a Field box then hit Enter to have it added as a Field (to apply a mashup).  

For this example, we will:

    1. Type "Mashup View" into the Add a Field blank.

     2. Press Enter to add it as a Field.

Locate the new Field in your list, then click the Prep icon.

Click the SQL Value icon.

For this example, we will select CONCAT from the options at the top.

Click CONCAT.  Notice the content in the Value box before you click it.

1. Notice how CONCAT appears in the Value box (after we clicked it):   CONCAT(?,?)  

2. Delete the words "mashup view."

Choose your first Field for the Concat (we will select Location for this example).

Choose your second Field for the Concat (we will select Date for this example).

Make certain that the Format is correct:     CONCAT(`?`,`?`)    

    1. We manually typed: " `Location`,`Date` " (to replace each "?" in the original formula).    

    2. Click Save.

Click the Run icon to apply the changes.  Notice that the CONCAT mashup puts data from two fields into ONE Field.