Enabling incremental updates
Data object stores (.data) containing cached data are typically updated regularly to provide the latest data to dashboards and reports. In some cases, you can speed up the generation process by using the incremental updates option. Instead of retrieving the full set of data rows each time the data object store is generated, the incremental updates option retrieves only additional data rows that meet specified criteria.
Use this option to add new data rows on a regular basis to a large set of legacy data. For example, a data object retrieves order information. When the data object is generated initially, it contains all the order information to date. Each week, a new data object store is generated to capture new order data. For cases like this, adding only the new data each week improves performance significantly.
Observe the following guidelines when designing a data object that uses the incremental update option:
For each update, you must specify which data rows to add to an existing data object store. To accomplish this task, create a parameter in the data object. In the example described previously, the data object would use a date-time parameter to specify which week of data to retrieve.
Data rows can only be added to the result set returned by a data set, provided that the data set definition does not change between updates. If you change the definition of a data set, for example, by adding or deleting a column, you must generate a new data object store without using the incremental updates option.
If the data object contains a cube and you want the cube to include the new data set rows, or if you change the cube definition, you must also generate a new data object store without the incremental updates option.

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