Composition of Operations Can build expressions using multiple operations Example:oA=c(rx s) rxS A BCDE 1 Cx 10 a aaaBβBβ 11- β 28 ab b 12222 00000 a b B D E OA=C(rx S) CX 10 a B 10 a B 20 b Database System Concepts-6th Edition 2.17 @Silberschatz,Korth and SudarshanDatabase System Concepts - 6 2.17 ©Silberschatz, Korth and Sudarshan th Edition Composition of Operations Can build expressions using multiple operations Example: A=C (r x s) r x s A=C (r x s)