. IBM Cognos 8 includes a debugging functionality that you can use to find problems with your drill-through definitions created in IBM Cognos Connection, and to correct any drill-through errors. It can also help you understand how the drill-through functionality works, especially across different types of data sources. This functionality is also referred to as the drill-through assistant. You can also debug drill-through definitions that were created in a PowerCube and migrated to IBM Cognos 8.
If your target report is not receiving any parameters, check the mapping in your drill-through definition, and ensure that your parameters were created against the correct data type for your drill-through scenario. For example, if you want to create a drill-through definition from an OLAP package to a target report based on a relational package, your target parameters need to be set up to a query item that has the same value as the OLAP business key or the member caption. For more information, see Members and Values.
If your target report is being filtered with the wrong values, check the values that are being mapped from the source to the target.
You must have the necessary permissions to use the drill-through assistant. The information that the drill-through assistant provides is available from the Go To page, when you run the drill-through. The drill-through assistant provides the following information.
The source values are the values from the selection context that are available for passing to the target report when the user chooses to drill through to the target report or object. For example, if you drill through from a source in Analysis Studio, you see the values at the intersection you selected prior to the drill-through action, and any values in the context area.
The values in the debug list are the values in the source report that were transformed by any drill-through operation.
Display Value
Shows the value that users see when using this data item or this member. For OLAP members, this is the member caption or label. For example: Telephone is a member from the Order Method dimension.
Use Value
Shows the value that IBM Cognos reports and analyses use when retrieving the data item or the member. For OLAP members, this is the member unique name (MUN). For example: [great_outdoors_company].[Order Method].[Order Method].[Order Method1]->:[PC].[@MEMBER].[2] is the MUN for the Telephone member in the Order Method dimension.
If you chose to use parameters in the target, then the target mapping shows the name of each parameter that was mapped in the drill-through definition, and the values that the source is attempting to pass to that parameter.
Parameter Name
Shows a list of valid target parameters mapped in the drill-through definition to receive information from the query item, level, or hierarchy on which you performed the drill-through action.
You can see only parameters for which there is a valid mapping and only the names of the parameters. For example, if the target report contains a parameter for Product Type and the drill-through definition maps that target parameter to the source Product Type level metadata, you see this target parameter only if you attempt to drill through on the Product Type level in the source report. Drilling through on the Product Line level does not display this parameter target.
You must ensure that the target parameters in your drill-through definitions are mapped correctly. Incorrectly mapped parameters can receive information from the wrong source metadata, especially where you have data values that are not unique. If you cannot see any target parameters or the parameters you expected to see in the View Target Mapping list, check the parameter mapping in the drill-through definition.
Display Value
Shows the value that users see when using a data item or member. For OLAP members, this is the member caption or label. For example: Telephone is a member from the Order Method dimension
Use Value
Shows the transformed value that the drill-through definition uses when passing a data item value or member to the target parameter.
OLAP members passed to relational target parameters obtain the business key from the members MUN and pass only the business key. Using the above example of the Telephone member in Order Methods, the business key is 2. If you are unsure of what the business key is for a member, you can write a Report Studio expression such as roleValue('_businessKey',[member]). This value is passed to the target parameter.
OLAP members passed to a target parameter based on another OLAP package of the same OLAP type show a transformed MUN. Using the above Order Methods example, the MUN is now transformed and the drill-through definition uses the value of [great_outdoors_company].[Order Method].[Order Method].[Order Method1]-> [Order Method1]. [2]:[PC].[@MEMBER].[2]. The middle portion of [Order Method1][2] is where the drill-through definition finds the correct member in the target when the OLAP data sources are different. To see the MUN for a specific member, you can look at the properties of the member in Report Studio (Professional authoring mode) and look at the Member Unique Name property.
You can use the drill-through assistant for debugging purposes when you work with drill-through definitions in IBM Cognos Connection.
To use this functionality, you must have the required
permissions for the Drill-Through Assistant secured
function in IBM Cognos Administration .
Select a link in your source report, right-click the link, and select Go To, or from PowerPlay Studio, click the drill-through button.
The Related links page appears, showing the list of available target reports. If your target report is not shown, review the scope settings in your drill-through definition.
Tip: If only one target is available, then when you select Related links, the target is opened without showing the Go To page.
Click View passed source values to see the values that are available for passing by the source report.
Next to the target report, click the down arrow and choose View Target Mapping.
A list of the valid mapped data appears, showing the available source values, and the use and display values.
For either set of values, click More information to see the XML for the selection context (passed source) or the drill-through specification (target mapping.
Your OLAP source has a Products dimension with the levels Line, Type, and Name. You have defined a parameter in your relational target to match each level of that OLAP source dimension. You can have a situation where you see all target parameters from a single dimension displayed in the View Mapped Target list. This is likely because the individual target parameters are mapped to a single dimension in the drill-through definition, in this case the Products dimension. In your OLAP data source, you have a business key value, or the source value used to create the members, that is duplicated in all three levels.
Parameter Name | Display Value | Use Value |
Prod Line Param | Camping Equipment | 1 |
Product Type Param | Cooking Gear | 1 |
Product Name Param | Trail Chef Water Bag | 1 |
Having all three parameters mapped to the Products dimension is correct if the use values are not duplicated in the dimension. In the above table, you can see that members from all three levels have the same use value. In this case the drill-through operation cannot determine which level is the correct one because the scenario indicates that all levels are valid. In this situation, the first level encountered with a valid business key or use value is fulfilled by the drill-through definition. This can result in unexpected behavior.
This example shows why it is important to always ensure that your data warehouses and OLAP sources are designed with unique business keys or source values. To correct this situation, the drill-through definition should have each individual target parameter mapped to each associated level in the source metadata rather than in the dimension.
