1. A method for managing data in a database system, comprising the steps of: said database system maintaining (a) data that identifies one or more relational tables as tables that store data associated with the content of resources that belong to an information hierarchy, and (b) connection criteria that indicates what constitutes a hierarchical relationship in the information hierarchy; wherein said one or more relational tables include at least one table that stores, along with the data associated with the content of the resources, certain data that serves as an external hierarchy definition that establishes hierarchical relationships between said resources; said database system maintaining information that captures said information hierarchy, as an internal hierarchy definition, in one or more hierarchy structures separate from said one or more relational tables; and wherein the step of maintaining information that captures said information hierarchy as an internal hierarchy definition includes said database system automatically maintaining consistency between said external hierarchy definition and said internal hierarchy definition.