Virtual Columns


It is possible to include data in a table visualization (or in labels and tooltips of some other visualizations) that is not part of the original data table. A virtual column connects to a remote data source and collects data from there. This can be useful if, for example, a large quantity of data is stored in a database and the Spotfire analysis file would be too large if the data was included. The virtual columns can contain plain text but a more common use might be if the collected data were to consist of images or other large files.

Note: A virtual column type needs to be registered programmatically. Virtual columns are not available by default.

Note: Virtual columns are not supported for tables using in-db data sources.

Differences between virtual columns and regular columns

In the context of the table visualization, there are no major differences except that you cannot sort by the virtual column. However, the virtual column is only part of the table visualization and not part of the data table. This means that:

The virtual column may take some time to load, especially if the column contains images. However, the column will not be loaded all at once. It is possible to start working with the column and the contents will be loaded as you scroll down in the table. The remote data source from where the virtual column is retrieved may require you to enter a username and password.

See also:

What is a Table?

How to Use the Table

Images in Tables

Table Properties - Virtual Columns