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Cube Building and Modifying Examples

Adding Data to a Cube with Cube Update

After you have built a cube with either a detail table or a star schema, you can update the cube with the Incremental Update function in SAS OLAP Cube Studio. You can choose to update the original cube or generate an updated generation (copy) of the cube. You can then choose to coalesce (consolidate) the aggregation racks (SPDE tables) that have been created during the cube update into a single SPDE table.

Note:   For more information on updating SAS OLAP cubes, see Updating SAS OLAP Cubes.  

Update a Cube In-Place

The Update In-Place function enables you to update the original cube. In SAS OLAP Cube Studio select a cube from the tree view that you want to update. You can then right-click on the cube and select Incremental Update Update In-Place. You can also select the function from the Actions menu.

On the Update General page of the Incremental Update wizard, select the source table that you will use to update the cube with. If you are updating a star schema cube, the check box Add data during update is available. If selected, it activates the New source table box. Select a new source table. You can also click on Select and choose a table that is not in the drop-down list. If a drill-through table is included in the cube update, click Select beside the New drill-through table text field and choose a drill-through table. If the cube was originally built without a drill-through table, the option (none) is listed in the Current drill-through table text field.

If you are updating a star schema cube, you can also specify how missing dimension keys are handled if encountered. Select one of the three radio button options under When searching through new members in a table and a missing key is encountered.

Note:   Because you are updating the original cube with the Update In-Place function, the fields for Cube Name, OLAP Schema, and Location are inactive.  

You can also select Advanced and specify aggregation performance options, any needed SAS code, and a search path for user-written formats to include with the cube update. Select Next when you are finished.

On the Dimension Selection page, you can click a dimension in the Select a dimension list. You can then select one of the radio buttons under Select an update process method. When the cube was originally built, you could also specify whether a dimension could be updated at a later time or not. Any dimensions that cannot be updated are listed in the Blocked from new member updates list and are not available for selection.

If you are updating a star schema cube, you can select a dimension table that can be used to update an individual dimension. Each dimension has a default table assigned from the original cube build. Using the left and right arrow keys, you can move tables between the Available tables and the Selected table lists. You can also view statistics about the table you are selecting with the Properties, View Data, and Table Options buttons. If the table you want to use is not included in the Available Tables list, you can register the table with the Register Table button. Select Next when you are finished.

On the Summary of Selections page, review the generated PROC OLAP code that is used to update the cube. You can save the PROC OLAP code to a file by selecting Export Code. Select the Finish to run the update of the cube.

Generating a New Cube

The Generate New Cube function enables you to create an updated copy of the original cube without modifying the original cube. It is useful for cubes that are in a production environment, as it enables the system administrator to check the cube generation for accuracy before making it avaliable for user queries. In SAS OLAP Cube Studio, select a cube from the tree view that you want to update. You can then right-click the cube and select Incremental Update Generate New Cube. You can also select the function from the Actions menu. This opens the Update General page of the Incremental Update wizard.

Because you are creating a generation of the original cube, you must enter a cube name that is different from the original cube in the Cube Name text box. You can also change the OLAP schema and the folder location for the new cube.

You can then select the source table that you will use to update the cube with. If you are updating a star schema cube, the check box Add data during update is available. If selected, it activates the New source table box. Select a new source table. You can also click Select and choose a table that is not in the drop-down list.

If a drill-through table is included in the cube update, click Select beside the New drill-through table text field and choose a drill-through table. If the cube was originally built without a drill-through table, the option (none) is listed in the Current drill-through table text field.

If you are updating a star schema cube, you can also specify how missing dimension keys are handled if encountered. Select one of the three radio button options under When searching through new members in a table and a missing key is encountered.

You can also select Advanced and specify aggregation performance options, any needed SAS code, and a search path for user-written formats to include with the cube update. Select Next when you are finished.

On the Dimension Selection page, you can click a dimension in the Select a dimension list. You can then select one of the radio button options under Select an update process method. When the cube was originally built, you could also specify whether a dimension could be updated at a later time or not. Any dimensions that cannot be updated are listed in the Blocked from new member updates list and are not available for selection.

If you are updating a star schema cube, you can select a dimension table that can be used to update an individual dimension. Each dimension has a default table assigned from the original cube build. Using the left and right arrow keys, you can move tables between the Available tables and the Selected table lists. You can also view statistics about the table you are selecting with the Properties, View Data, and Table Options buttons. If the table you want to use is not included in the Available Tables list, you can register the table with the Register Table button. Select Next when you are finished.

On the Summary of Selections page, review the generated PROC OLAP code that is used to update the cube. You can save the PROC OLAP code to a file by selecting Export Code. Select Finish to run the update of the cube.

Coalesce Incremental Data for a Cube

After a cube has been updated, you can choose to combine the aggregation racks (SPDE tables) that have been created during the cube update into a single SPDE table. In SAS OLAP Cube Studio, select a cube from the tree view. You can then right-click the cube and select Incremental Update  Coalesce Inremental Data. You can also select the function from the Actions menu. This opens the Aggregations page of the Coalesce Incremental Data wizard.

On the Aggregations page, you can view the aggregations that will be coalesced from the Selected aggregations list. You can also observe the levels of the selected aggregations in the Select aggregations to preview levels list. The preview list is display only. Select Next.

On the Performance Options page, you can specify query performance settings for the cube aggregations. The Default tab enables you to change performance settings for all aggregations of the cube. Enter any needed setting values. Select the Next when you are finished.

On the Summary of Selections page, review the generated PROC OLAP code that is used to coalesce the aggregations. You can save the PROC OLAP code to a file by selecting Export Code. Select Finish to run the update of the cube.

A progress dialog box displays after you select Finish.

The SAS log that is generated contains status information for the coalesce process.

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