Cascading LOVs work nicely in Web Intelligence. They don’t really create a cascading LOV. They create a hierarchical LOV. But that works well. The hierarchical LOVs that we create in Designer don’t work well in Web Intelligence (They were designed for Desktop Intelligence). So, unless you’re using Deski, avoid them. Note that there is no way to do a true cascading LOV for Web Intelligence. Also, if you have a LOV for an ID field, it can be very helpful to add a second column to the LOV, which displays the description for each ID.
