Select Silent Refresh when the data has been modified in the data source and Cognos Insight is aware of the location of the data source. This option is selected when there is no change to the metadata, meaning no columns have been added or deleted from the source. While the mappings are unchanged, this option will refresh the data in Cognos Insight.
Use Guided Refresh when the source data has been modified in terms of the data structure. This will bring up the import wizard that will provide the flexibility in importing data. Follow the wizard, as described earlier...
silent and guided refresh definitions
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