Systems and techniques for mapping data structures in a data processing environment to help ensure the accessibility of stored information. In one implementation, an article includes a machine-readable medium storing instructions. The instructions are operable to cause one or more machines to perform operations. The operations include receiving a first data storage schema in which a characteristic in a first dimension table is mapped by a first table and a second table and generating a second data storage schema. The first table maps the characteristic to a first object that include attributes to which time information is irrelevant to data processing activities and the second table maps the characteristic to a second object that include attributes to which time information is relevant to data processing activities. The second data storage schema includes a fact table including at least some facts drawn from the first data storage schema and a second dimension table that includes at least some characteristics drawn from at least one of the first object and the second object.