Volume modelling, finite element computation and spatial information systems have a common basis in topology, especially in the theory of complexes which are higher dimensional generalization of graphs. A complex is a topological space having a certain algebraic structure called “chain complex” and due to its similarity to real world buildings a special kind of complexes are even called “buildings” in mathematics. So it would be consequent to base a building information system upon this theory or at least try to do so. Some manipulations and queries of such spaces can then be expressed by mappings which are similar to complex-morphisms and generalize the well known Euler operators. Other practical useful operations like assigning a detail to a spatial element (“refinement”), hiding details at lower scale views (“coarsening”) or spatial versioning, however, need a somewhat different kind of mappings. This paper shows a simple relational database representation of a finite complex as a basis for a database backed building information system. The implementation of operations on such a relational complex in Java will also be shown.