Representation of Geometric Constructs line segment {(x1,y1),(x2,y2)》 3 triangle {(x1,y1),(x2y2),(x3,y3)} 2 2 3 polygon {(x1,y1),(x2,y2),(x3,y3),(x4,y4),(x5,y5)} 4 5 2 3 {(x1y1),(x2,y2),(x3,y3),ID1 polygon {(x1,y1),(x3,y3),(x4,y4),ID1 {(x1,y1),(x4y4),(x5,y5),ID1} 4 5 object representation 10 Database System Concepts,5th Ed. 24.10 ©Silberschat乜，Korth and SudarshanDatabase System Concepts, 5 24.10 ©Silberschatz, Korth and Sudarshan th Ed. 10 Representation of Geometric Constructs