### Unique Key dialog

The dialog appears when you click the Incremental Fetch button in the Real-time Settings dialog. It helps you to specify a unique key for a real time chart. See the dialog.

Resources

Lists all the available data resources in the dataset used by the real time chart.

Adds the selected fields to the Unique Key box.

Removes the selected fields from the Unique Key box if they are not required.

Unique Key

Lists the fields you have added as the unique key, which is used to guarantee there are no two records with the same unique key value in the real time chart.

When a real time chart is specified with a unique key, each time when the chart automatically updates itself, the data that has the same unique key value as the previous loaded data records will be filtered and only data with different unique key value will be added to the chart. For instance, if you add the fields Country and Product ID as the unique key of a real time chart, when a record with the product ID 1 in USA has already been loaded into the chart, no more records of this product ID in USA will be added to the real time chart because they have the same unique key value.

OK

Closes this dialog and applies the unique key to the real time chart.

Cancel

Cancels specifying the unique key and closes this dialog.

Displays the help document about this feature.

Ignores the setting and closes this dialog.

###### Related topics:

- Configuring real time chart settings