Event-based incremental updating of cadastral database

Incremental updating of cadastral database means that master spatial data set is updated when any change (geometric or semantic) occurs, the change can be recorded, updated and provided successively to users. During this process, a set of editing operations is needed to add, delete or amend cadastral spatial objects (intermediate points, boundary points, boundary segment, and parcels). An event-based automatic (or semi-automatic) incremental updating of cadastral database method (named as EBIU-CDB) is presented in this paper, which is based on the land subdivision event and the topological relationship between two parcels. The land subdivision event (including split, union, reallocation and modification of the common border between two parcels) is given at first; an extended 4-intersection model used to describe the topological relations between two parcels is presented, 7 kinds of possible topological relations between two parcels at the same time are concluded by this method; split event is used as an example to illustrate EBIU-CDB, 7 kinds spatial change of split event are presented, and the updating algorithm is followed. The approach was implemented using VC++ in ORACLE9I SPATIAL and MAPINFO 6.5 platform.