When is it recommended to run schema validation during product upgrades?

Running schema validation during product upgrades is especially recommended to identify problems with the database. As systems and applications evolve, updates to the product may introduce changes to the database schema, such as new tables or changes to existing table structures. By validating the schema, you ensure that the database is aligned with the expected structure. This process helps uncover any discrepancies or issues, such as missing tables, incorrect data types, or constraints that may not be compatible with the new product version. Early identification of these problems can prevent further complications during the upgrade, ensuring a smoother transition to the new version.

Other options do not directly relate to the primary purpose of schema validation during upgrades. User permissions relate more to security settings rather than structural integrity, measuring system performance focuses on how well the system runs rather than its structural correctness, and changing database structures typically refers to the actions taken post-validation rather than the validation process itself.