Event-driven Incremental Updating of Cadastral Spatial Database Considering Topological Integrity

In order to update the cadastral database and maintain it's topological consistency automatically (or semi-automatically) during the updating process, an event-driven incremental updating method of cadastral database considering topological integrity is proposed in this paper. In this method, five kinds of cadastral spatial change is divided to five kinds of basic events: node-moving, union, splitting, rectification, and reallocation; The states (including the entities and topology) involved in union, splitting and rectification are analyzed when the parcel including the parcel with one hole; a set of spatial change identification rules used to determine the spatial changes of the entities involved in cadastral event are developed based on the topological consistency rules, the semantic of the entities and the topological relationship between the involved entities before and after change, then the changes of each entity involved in all cadastral spatial change events can be inferred according to these rules; a set of updating operators mapping the spatial changes of each entity to the corresponding identity-based changes of single spatial object are designed and implemented; in order to assure the updating operations can be completely implemented at the correct sequence, the topological integrity can be maintained well, the formal representation of updating process are present. Thus when any cadastral spatial change event occur and submission, an updating program can be triggered automatically to update the cadastral database and maintain the integrity of the spatial data, The approach was implemented using VC in Oracle10 Spatial and MapX platform, the algorithms are checked by real and simulation data.