Caching Engine



In PowerOLAP® there is a caching feature embedded in each Cube. When users calculate values, the values are rolled up into aggregates and based on the costing algorithms those values are cached. By default, this feature is embedded in each Cube.

Caching feature in PowerOLAP®

There are certain instances when people make request in a Cube where Caching would be a very expensive operation. Such calculation usually involves requesting or accessing large number of data points from a Cube. An example would be creating a constrained Slice and nesting multiple Dimensions among rows and columns and then constraining that Slice.

Literally, what it does is it is turning the multidimensional space into a transactional report writer. In that instance you may be asking for thousands or even millions of data points and asking the engine to remove any of those values that are zero and return only the non zero values.

Another instance where this might be the case is with the use of API. Through the API, users can ask for large quantities of data points for purpose such as exporting them into another system.

Exporting PowerOLAP® is another feature. Exporting a large section of Cube might be an instance for user to ask for numerous data points. By un-checking the Enable Caching checkbox located in the Cubes dialog box, you are telling PowerOLAP®that upon receiving request for data points, not to cache values and instead simply take the large number of data points being requested, pass it directly to the calculation engine and perform a large calculation on each of those points or all of those points in a single pass. In other words, PowerOLAP® will not do a point by point calculation but will do a single large calculation for all the requested data points.

Caching Engine is an advance feature and it highly advisable that it should only be used when the user understands its implications and when they have an understanding of when and where to use it.

To Enable/Disable Caching in PowerOLAP®:

1.   In the PowerOLAP ribbon, select Model tab and Cubes command.
The Cubes dialog box is opened.

2.   Select the appropriate cube (e.g., Future Year Model)

3.   Click on the Properties button.
This will bring up the Cube Properties dialog box.

4.   Check the Enable Caching checkbox to turn on the option, otherwise leave it blank or uncheck it.

Note that by default the caching feature is enabled in each cube by default.