When importing data from an external data source it can appear that some data is duplicated.  One reason this happens is due to extra white space in the data field.  Spotfire will see:

"Data"
" Data"
"Data "

as unique entries.

Using the Trim() function can resolve this issue, as it removes all white space from data fields.

1. Click on Data/Transform data
2. Select the affected data table
3. Under Transformations: select 'Calculate and replace column', then click on "Insert"
4. For the Expression: enter Trim([Column]), then click "OK", and "OK" again

This will remove white space when importing the data, and should clear up any unexpected duplicates.