A computer automatically reads each object in a metadata that is descriptive of a database. Then the computer automatically applies a number of rules, to check if the object triggers a rule. If so, then the computer automatically changes the metadata as per an action identified by the triggered rule. After all rules are applied to the object, and after all objects in the metadata are processed, the resulting metadata is used to change the database's structure. The objects may be read from the metadata in an order (e.g. hierarchy) specified in meta-metadata that is descriptive of the metadata.