☒无法显示该图片。 Spatial and Geographic Databases Database System Concepts,6th Ed. @Silberschatz,Korth and Sudarshan See www.db-book.com for conditions on re-useDatabase System Concepts, 6th Ed. ©Silberschatz, Korth and Sudarshan See www.db-book.com for conditions on re-use Spatial and Geographic Databases