When must a rule be validated?

A rule must be validated when deploying the cube. This validation process ensures that the rules are syntactically and logically sound before the cube is made operational. During deployment, the rules are checked to confirm that they correctly reflect the intended calculations and that there are no errors that could disrupt the functioning of the cube. Validation at this stage is crucial because any discrepancies can lead to incorrect data processing or unexpected behavior within the application once it is in use.

While calculations and saving might involve checks for adherence to certain conditions, the specific requirement to validate rules arises prominently during the deployment phase when all components of the cube are integrated and prepared for execution.