Spatial data are often stored in a database with the finest level of details. The problem of cartographic generalization of spatial data concerns deriving spatial data with proper level of details when the data are used for an application. With more and more computerized applications making use of shared spatial data sources, and the increasing number of applications emerging from Internet-based spatial applications, efficient spatial data generalization becomes a critical issue. In this paper, the issues in efficient spatial data generalization are investigated,with a unique focus on spatial database design and spatial operations processing.Several types of a commonly used spatial indexing mechanism called z-values are proposed to achieve the goals.