ngocha85: Giáo trình Cơ sở dữ liệu Giaùo trình CÔ SÔÛ DÖÕ LIEÄU Trang Bộ môn CSDL Trường CĐCN 4 1 MỤC LỤC Chöông 1 ..............................................................................................................................................3 MOÂ HÌNH QUAN HEÄ ..........................................................................................................................3 I NGUYEÂN NHAÂN RA ÑÔØI CUÛA MOÂ HÌNH QUAN HEÄ .........................................................3 II CÔ SÔÛ DÖÕ LIEÄU VAØ HEÄ QUAÛN TRÒ CÔ SÔÛ DÖÕ LIEÄU.........................................................3 1 CSDL laø gì?...........................................................................................................................4 2 Heä quaûn trò CSDL .................................................................................................................4 3 Ngöôøi duøng (User).................................................................................................................4 4 CSDLQH vaø Heä taäp tin theo loái cuõ .......................................................................................5 III MOÂ HÌNH QUAN HEÄ ...........................................................................................................5 1 Moâ hình quan heä laø gì ?.........................................................................................................5 2 Caùc khaùi nieäm cô baûn cuûa moâ hình quan heä .........................................................................6 3 Caùc pheùp toaùn taäp hôïp ........................................................................................................10 4 Caùc pheùp toaùn quan heä........................................................................................................11 5 Caùc tính chaát cuûa ñaïi soá quan heä ........................................................................................12 IV MOÂ HÌNH THÖÏC THEÅ KEÁT HÔÏP......................................................................................15 1 Giôùi thieäu moâ hình thöïc theå keát hôïp ...................................................................................15 2 Chuyeån töø moâ hình thöïc theå keát hôïp sang löôïc ñoà CSDL...................................................17 V BAØI TAÄP .................................................................................................................................19 1 Pheùp toaùn taäp hôïp vaø pheùp toaùn quan heä............................................................................19 2 Moâ hình thöïc theå keát hôïp ....................................................................................................20 Chöông 2 ............................................................................................................................................22 NGOÂN NGÖÕ TRUY VAÁN SQL..........................................................................................................22 I CAÙCH TAÏO QUAN HEÄ BAÈNG ACCESS ..............................................................................22 II CAÂU LEÄNH TRUY VAÁN........................................................................................................22 1 BIEÅU THÖÙC (EXPRESSION) ............................................................................................22 2 CAÂU LEÄNH SQL................................................................................................................25 III BAØI TAÄP .............................................................................................................................28 Chöông 3 ............................................................................................................................................32 RAØNG BUOÂC TOAØN VEÏN QUAN HEÄ..............................................................................................32 I RAØNG BUOÄC TOAØN VEÏN - CAÙC YEÁU TOÁ CUÛA RAØNG BUOÄC TOAØN VE