SYMPTOM:
When users run a report that contains a hierarchy on the template or has a hierarchy in the page-by, the following error occurs:

SQLEngine got an Exception from DFC: Engine Logic: ERROR: CompUnit is empty. The join tree is empty. Please check if the metric has calculation level.
The Report Editor shows the following information:

This error may be caused by the current state of the schema. The scehma may need to be updated. Double click here to update schema.
Also, when the report is re-executed after being executed by double-clicking the report in Strategy Desktop 8.x, the following error occurs:

Object variable or With block variable not set
CAUSE:
A hierarchy has been placed either on the report or within the page-by, but the report does not include a filter. The hierarchy on the report is unresolved. The engine queries the filters on the report to decide for which attribute, from the hierarchy, the report should show details.
ACTION:
Place an attribute filter on the report. The attribute must exist within the specific hierarchy placed on the template or page-by of the report.