Complex data types, like JSON object fields and arrays can't be directly union-ed. However, you can use the data browser or the pull operation to extract individual fields from within an object and union those individual fields. To access the data browser on a JSON object column, double-click on a cell in the column. To access the data browser for an entire row of data, double-click on one cell in the DATA column at the end of the row. From the data browser, click on a field within an object or array to pull it into the table.
Did you have any other questions about this, Teresa?