Entities in the real world have non-spatial attributes, as well as spatial and temporal features. A spatial-temporal data
model aims at describing appropriately these intrinsic characteristics within the entities and model them on a conceptual
level so that the model can present both static information and dynamic information that occurs over time. In this paper,
we devise a novel spatial-temporal data model which is based on Geodatabase. The model employs object-oriented
analysis method, combining object concept with event. The entity is defined as a feature class encapsulating attributes
and operations. The operations detect change and store the changes automatically in a historic database in Geodatabase.
Furthermore, the model takes advantage of the existing strengths of the relational database at the bottom level of
Geodatabase, such as trigger and constraint, to monitor events on the attributes or locations and respond to the events
correctly. A case of geographic database for Kunming municipal sewerage geographic information system is
implemented by the model. The database reveals excellent performance on managing data and tracking the details of
change. It provides a perfect data platform for querying, recurring history and predicting the trend of future. The instance
demonstrates the spatial-temporal data model is efficient and practicable.
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