TIBCO Spotfire:A Comprehensive Primer(Second Edition)
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Advanced topic – key columns

There's one important caveat with bookmarks. If you want bookmarks to capture markings between data updates, then you must allocate key columns to the underlying data table. Otherwise, Spotfire won't be able to determine which rows of data to mark as it won't have any reference to know which rows to mark when the data is updated.

Setting key columns is only available in Analyst clients. Let's set them now:

  1. Click EditData Table Properties.
  2. Make sure the default data table is selected.
  3. Locate the Key columns for linked data: box and click the Edit... button:
  1. We need to find columns that uniquely identify the rows in the data. Unfortunately, Spotfire thinks that Name and Sector might be suitable, but neither of these, nor their combination, uniquely identifies every row (there are rows for every date for each Name). To fix this, choose All columns from the Limit available columns to: dropdown.
  1. Add the Name and Date columns to the Selected columns: box in the dialog:

Now, when you update the data, marking will mark these rows when the data is updated and you apply the bookmark. If you didn't do this, Spotfire would not be able to identify the rows and so wouldn't apply any marking at all. Remember that marking using bookmarks in Spotfire is chiefly for the purpose of capturing the exact current state of the marking.

Imagine you marked all rows for PCLN, saved a bookmark, and then next time the data was updated, you wanted Spotfire to mark all rows for PCLN including any newly available data. This wouldn't be possible, since Spofire does not support "symbolic" marking currently. This use case is far better achieved by using filtering rather than marking.