Dependent LOVs in Discoverer Admin

Question

Hi All,
Can we create dependent LOVs in Discoverer. If yes can anyone throw some light that.
regards,
gt1982

Answer 1

Well, let me try to clarify what Tamir said. I think you probably will need to do some setup work in Administrator. I am assuming that you want to do something like this in a worksheet - The user first clicks the LOV indicator on the Region parameter and picks a region from the Region LOV (say they pick the East region value), and then based on that region value, when they click on the City parameter LOV icon, the list of cities they see is filtered so that they only see cities in the East region (say New York City and Boston). To do this correctly in a worksheet, you need to define an Item Hierarchary in Discoverer Administrator. The two parameters must have some kind of relationship in the database to make this work.
Then once you have the item hierarchy defined, the rest of your work is in Discoverer Plus. You create the first parameter in the worksheet. In my example, you would create the Region parameter first. Next you would create your second parameter (in my example, that would be the City parameter). When creating the second parameter, that is when that section on the parameter window ("Do you want to filter the list of values for this parameter") comes into play. You will want to select the "Filter the list of values based on the selected conditions" option, and then find the condition name (for the Region parameter created condition) and select that condition. The term Oracle uses for this is "Cascading Parameters". So if you search on that term in the Discoverer Plus user guide, that will give you more information on this process.
Now, you do have to be careful. Ideally the folder with the relationship between the two parameters is based on a master table, not a detail table. If based on a detail table, you can run into performance problems when clicking on the LOV icon for the second parameter. The system may take forever to try to build that second LOV.
But the process does work. I have used it a couple of times.
Hope this helps a bit. Good luck.
John Dickey