Thu\u1ed9c t\u00ednh<\/h3>\n
C\u00e1c thu\u1ed9c t\u00ednh l\u00e0 c\u00e1c \u0111\u1eb7c t\u00ednh ho\u1eb7c \u0111\u1eb7c \u0111i\u1ec3m c\u1ee7a c\u00e1c th\u1ef1c th\u1ec3. Ch\u00fang \u0111\u01b0\u1ee3c bi\u1ec3u di\u1ec5n d\u01b0\u1edbi d\u1ea1ng h\u00ecnh elip k\u1ebft n\u1ed1i v\u1edbi c\u00e1c th\u1ef1c th\u1ec3. C\u00e1c thu\u1ed9c t\u00ednh c\u00f3 th\u1ec3 l\u00e0 \u0111\u01a1n gi\u1ea3n (nguy\u00ean t\u1eed) ho\u1eb7c ph\u1ee9c h\u1ee3p (g\u1ed3m nhi\u1ec1u thu\u1ed9c t\u00ednh \u0111\u01a1n gi\u1ea3n).<\/p>\n
Kh\u00f3a<\/h3>\n
Kh\u00f3a l\u00e0 c\u00e1c thu\u1ed9c t\u00ednh ho\u1eb7c t\u1eadp h\u1ee3p c\u00e1c thu\u1ed9c t\u00ednh gi\u00fap x\u00e1c \u0111\u1ecbnh duy nh\u1ea5t m\u1ed9t th\u1ef1c th\u1ec3. C\u00f3 hai lo\u1ea1i kh\u00f3a ch\u00ednh:<\/p>\n
- \n
- Kh\u00f3a ch\u00ednh<\/strong>: M\u1ed9t \u0111\u1ecbnh danh duy nh\u1ea5t cho m\u1ed9t th\u1ef1c th\u1ec3.<\/li>\n
- Kh\u00f3a ngo\u1ea1i<\/strong>: M\u1ed9t thu\u1ed9c t\u00ednh trong m\u1ed9t th\u1ef1c th\u1ec3 l\u00e0 kh\u00f3a ch\u00ednh trong th\u1ef1c th\u1ec3 kh\u00e1c, t\u1ea1o ra m\u1ed1i quan h\u1ec7 gi\u1eefa hai th\u1ef1c th\u1ec3.<\/li>\n<\/ol>\n
L\u1ee3i \u00edch c\u1ee7a vi\u1ec7c s\u1eed d\u1ee5ng ERD<\/h3>\n
- \n
- Bi\u1ec3u di\u1ec5n tr\u1ef1c quan<\/strong>: ERD cung c\u1ea5p m\u1ed9t bi\u1ec3u di\u1ec5n tr\u1ef1c quan r\u00f5 r\u00e0ng v\u00e0 s\u00fac t\u00edch v\u1ec1 c\u1ea5u tr\u00fac c\u01a1 s\u1edf d\u1eef li\u1ec7u, gi\u00fap d\u1ec5 hi\u1ec3u v\u00e0 truy\u1ec1n \u0111\u1ea1t h\u01a1n.<\/li>\n
- T\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u<\/strong>: B\u1eb1ng c\u00e1ch x\u00e1c \u0111\u1ecbnh c\u00e1c m\u1ed1i quan h\u1ec7 v\u00e0 kh\u00f3a, ERD gi\u00fap \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n v\u00e0 t\u00ednh nh\u1ea5t qu\u00e1n c\u1ee7a d\u1eef li\u1ec7u.<\/li>\n
- T\u00e0i li\u1ec7u<\/strong>: ERD \u0111\u00f3ng vai tr\u00f2 l\u00e0 t\u00e0i li\u1ec7u cho thi\u1ebft k\u1ebf c\u01a1 s\u1edf d\u1eef li\u1ec7u, h\u1ed7 tr\u1ee3 trong b\u1ea3o tr\u00ec v\u00e0 ph\u00e1t tri\u1ec3n trong t\u01b0\u01a1ng lai.<\/li>\n
- Giao ti\u1ebfp<\/strong>: ERD h\u1ed7 tr\u1ee3 giao ti\u1ebfp gi\u1eefa c\u00e1c b\u00ean li\u00ean quan, bao g\u1ed3m c\u00e1c nh\u00e0 thi\u1ebft k\u1ebf c\u01a1 s\u1edf d\u1eef li\u1ec7u, nh\u00e0 ph\u00e1t tri\u1ec3n v\u00e0 c\u00e1c nh\u00e0 ph\u00e2n t\u00edch kinh doanh.<\/li>\n<\/ol>\n
V\u00ed d\u1ee5 s\u01a1 \u0111\u1ed3 ERD c\u1ee7a n\u1ec1n t\u1ea3ng th\u01b0\u01a1ng m\u1ea1i \u0111i\u1ec7n t\u1eed<\/span><\/h3>\n
Xem x\u00e9t m\u1ed9t n\u1ec1n t\u1ea3ng th\u01b0\u01a1ng m\u1ea1i \u0111i\u1ec7n t\u1eed v\u1edbi c\u00e1c t\u00ednh n\u0103ng n\u00e2ng cao:<\/p>\n
- \n
- C\u00e1c th\u1ef1c th\u1ec3: Ng\u01b0\u1eddi d\u00f9ng, S\u1ea3n ph\u1ea9m, \u0110\u01a1n h\u00e0ng, Thanh to\u00e1n<\/li>\n
- Ph\u00e2n lo\u1ea1i con: Kh\u00e1ch h\u00e0ng, Ng\u01b0\u1eddi b\u00e1n<\/li>\n
- Th\u1ef1c th\u1ec3 li\u00ean k\u1ebft: Chi ti\u1ebft \u0111\u01a1n h\u00e0ng (\u0111\u1ec3 bi\u1ec3u di\u1ec5n s\u1ea3n ph\u1ea9m trong m\u1ed9t \u0111\u01a1n h\u00e0ng)<\/li>\n
- Thu\u1ed9c t\u00ednh \u0111a gi\u00e1 tr\u1ecb: Thu\u1ed9c t\u00ednh s\u1ea3n ph\u1ea9m (v\u00ed d\u1ee5: k\u00edch c\u1ee1, m\u00e0u s\u1eafc)<\/li>\n
- Thu\u1ed9c t\u00ednh suy ra: T\u1ed5ng gi\u00e1 \u0111\u01a1n h\u00e0ng<\/li>\n<\/ul>\n
![\"E-commerce](\"https:\/\/guides.visual-paradigm.com\/wp-content\/uploads\/2023\/09\/img_6503c87dd903b.png\")
<\/p>\nV\u00ed d\u1ee5 s\u01a1 \u0111\u1ed3 ERD \u2013 H\u1ec7 th\u1ed1ng qu\u1ea3n l\u00fd s\u00e1ch<\/h3>\n
S\u01a1 \u0111\u1ed3 ERD n\u00e0y m\u00f4 h\u00ecnh h\u00f3a m\u1ed9t h\u1ec7 th\u1ed1ng qu\u1ea3n l\u00fd s\u00e1ch bao g\u1ed3m t\u00e1c gi\u1ea3, nh\u00e0 xu\u1ea5t b\u1ea3n, kh\u00e1ch h\u00e0ng, s\u00e1ch, gi\u1ecf h\u00e0ng v\u00e0 kho h\u00e0ng. N\u00f3 ghi l\u1ea1i c\u00e1c m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c th\u1ef1c th\u1ec3 n\u00e0y, ch\u1eb3ng h\u1ea1n nh\u01b0 nh\u1eefng cu\u1ed1n s\u00e1ch n\u00e0o do t\u00e1c gi\u1ea3 n\u00e0o vi\u1ebft, nh\u1eefng cu\u1ed1n s\u00e1ch n\u00e0o do nh\u00e0 xu\u1ea5t b\u1ea3n n\u00e0o ph\u00e1t h\u00e0nh, nh\u1eefng cu\u1ed1n s\u00e1ch n\u00e0o n\u1eb1m trong gi\u1ecf h\u00e0ng n\u00e0o, v\u00e0 nh\u1eefng cu\u1ed1n s\u00e1ch n\u00e0o \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong kho h\u00e0ng n\u00e0o. Vi\u1ec7c s\u1eed d\u1ee5ng kh\u00f3a ch\u00ednh v\u00e0 kh\u00f3a ngo\u1ea1i \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n v\u00e0 nh\u1ea5t qu\u00e1n d\u1eef li\u1ec7u trong c\u01a1 s\u1edf d\u1eef li\u1ec7u.<\/p>\n
\u00a0<\/p>\n
![\"ERD](\"https:\/\/cdn-images.visual-paradigm.com\/guide\/data-modeling\/what-is-erd\/01-entity-relationship-diagram.png\")
<\/p>\nC\u00e1c th\u1ef1c th\u1ec3 v\u00e0 thu\u1ed9c t\u00ednh c\u1ee7a ch\u00fang<\/h3>\n
- \n
- \n
T\u00e1c gi\u1ea3<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
T\u00ean<\/code>: varchar(255), kh\u00f4ng \u0111\u01b0\u1ee3c \u0111\u1ec3 tr\u1ed1ng.<\/li>\n\u0110\u1ecba ch\u1ec9<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\nURL<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho c\u00e1c t\u00e1c gi\u1ea3 vi\u1ebft s\u00e1ch. M\u1ed7i t\u00e1c gi\u1ea3 c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u cu\u1ed1n s\u00e1ch.<\/li>\n<\/ul>\n<\/li>\n
- \n
Nh\u00e0 xu\u1ea5t b\u1ea3n<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
T\u00ean<\/code>: varchar(255), kh\u00f4ng \u0111\u01b0\u1ee3c \u0111\u1ec3 tr\u1ed1ng.<\/li>\n\u0110\u1ecba ch\u1ec9<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\nS\u1ed1 \u0111i\u1ec7n tho\u1ea1i<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\nURL<\/code>: integer(10), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho c\u00e1c nh\u00e0 xu\u1ea5t b\u1ea3n ph\u00e1t h\u00e0nh s\u00e1ch. M\u1ed7i nh\u00e0 xu\u1ea5t b\u1ea3n c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u cu\u1ed1n s\u00e1ch.<\/li>\n<\/ul>\n<\/li>\n
- \n
Kh\u00e1ch h\u00e0ng<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
Email<\/code>: varchar(255), kh\u00f3a ch\u00ednh.<\/li>\nT\u00ean<\/code>: varchar(255), kh\u00f4ng \u0111\u01b0\u1ee3c \u0111\u1ec3 tr\u1ed1ng.<\/li>\nS\u1ed1 \u0111i\u1ec7n tho\u1ea1i<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\n\u0110\u1ecba ch\u1ec9<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho kh\u00e1ch h\u00e0ng mua s\u00e1ch. M\u1ed7i kh\u00e1ch h\u00e0ng c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u gi\u1ecf h\u00e0ng.<\/li>\n<\/ul>\n<\/li>\n
- \n
S\u00e1ch<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
ISBN<\/code>: varchar(255), kh\u00f3a ch\u00ednh.<\/li>\nT\u00ean nh\u00e0 xu\u1ea5t b\u1ea3n<\/code>: varchar(255), kh\u00f4ng \u0111\u01b0\u1ee3c \u0111\u1ec3 tr\u1ed1ng.<\/li>\nT\u00ean t\u00e1c gi\u1ea3<\/code>: varchar(255), kh\u00f4ng \u0111\u01b0\u1ee3c \u0111\u1ec3 tr\u1ed1ng.<\/li>\n\u0110\u1ecba ch\u1ec9 t\u00e1c gi\u1ea3<\/code>: varchar(255), c\u00f3 th\u1ec3 null.<\/li>\nN\u0103m<\/code>: integer(10), c\u00f3 th\u1ec3 null.<\/li>\nTi\u00eau \u0111\u1ec1<\/code>: varchar(255), c\u00f3 th\u1ec3 null.<\/li>\nGi\u00e1<\/code>: numeric(19, 0), c\u00f3 th\u1ec3 null.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho c\u00e1c cu\u1ed1n s\u00e1ch v\u1edbi th\u00f4ng tin chi ti\u1ebft v\u1ec1 nh\u00e0 xu\u1ea5t b\u1ea3n, t\u00e1c gi\u1ea3 v\u00e0 c\u00e1c \u0111\u1eb7c \u0111i\u1ec3m c\u1ee5 th\u1ec3 c\u1ee7a s\u00e1ch.<\/li>\n<\/ul>\n<\/li>\n
- \n
ShoppingBasket_Book<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
ShoppingBasketID<\/code>: integer(10), kh\u00f3a ngo\u1ea1i tham chi\u1ebfu \u0111\u1ebfn\u00a0ShoppingBasket(ID)<\/code>.<\/li>\nBookISBN<\/code>: varchar(255), kh\u00f3a ngo\u1ea1i tham chi\u1ebfu \u0111\u1ebfn\u00a0Book(ISBN)<\/code>.<\/li>\nS\u1ed1 l\u01b0\u1ee3ng<\/code>: integer(10), c\u00f3 th\u1ec3 null.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho m\u1ed1i quan h\u1ec7 nhi\u1ec1u-\u0111a gi\u1eefa gi\u1ecf h\u00e0ng v\u00e0 s\u00e1ch, cho bi\u1ebft nh\u1eefng cu\u1ed1n s\u00e1ch n\u00e0o n\u1eb1m trong gi\u1ecf h\u00e0ng n\u00e0o v\u00e0 s\u1ed1 l\u01b0\u1ee3ng c\u1ee7a ch\u00fang.<\/li>\n<\/ul>\n<\/li>\n
- \n
Gi\u1ecf h\u00e0ng<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
ID<\/code>: s\u1ed1 nguy\u00ean(10), kh\u00f3a ch\u00ednh.<\/li>\nCustomerEmail<\/code>: varchar(255), kh\u00f3a ngo\u1ea1i tham chi\u1ebfu \u0111\u1ebfn\u00a0Customer(Email)<\/code>.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho gi\u1ecf h\u00e0ng thu\u1ed9c v\u1ec1 kh\u00e1ch h\u00e0ng, bao g\u1ed3m nhi\u1ec1u s\u00e1ch.<\/li>\n<\/ul>\n<\/li>\n
- \n
Warehouse_Book<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
WarehouseCode<\/code>: s\u1ed1 nguy\u00ean(10), kh\u00f3a ngo\u1ea1i tham chi\u1ebfu \u0111\u1ebfn\u00a0Warehouse(M\u00e3)<\/code>.<\/li>\nBookISBN<\/code>: varchar(255), kh\u00f3a ngo\u1ea1i tham chi\u1ebfu \u0111\u1ebfn\u00a0Book(ISBN)<\/code>.<\/li>\nS\u1ed1 l\u01b0\u1ee3ng<\/code>: s\u1ed1 nguy\u00ean(10), c\u00f3 th\u1ec3 null.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho m\u1ed1i quan h\u1ec7 nhi\u1ec1u-\u0111a gi\u1eefa kho v\u00e0 s\u00e1ch, cho bi\u1ebft nh\u1eefng cu\u1ed1n s\u00e1ch n\u00e0o \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong kho n\u00e0o v\u00e0 s\u1ed1 l\u01b0\u1ee3ng c\u1ee7a ch\u00fang.<\/li>\n<\/ul>\n<\/li>\n
- \n
Kho<\/strong>:<\/p>\n
- \n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
M\u00e3<\/code>: s\u1ed1 nguy\u00ean(10), kh\u00f3a ch\u00ednh.<\/li>\n\u0110i\u1ec7n tho\u1ea1i<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\n\u0110\u1ecba ch\u1ec9<\/code>: varchar(255), c\u00f3 th\u1ec3 \u0111\u1ec3 tr\u1ed1ng.<\/li>\n<\/ul>\n<\/li>\n- M\u00f4 t\u1ea3<\/strong>: \u0110\u1ea1i di\u1ec7n cho c\u00e1c kho ch\u1ee9a s\u00e1ch.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n
Quan h\u1ec7<\/h3>\n
- \n
- \n
T\u00e1c gi\u1ea3 \u0111\u1ebfn S\u00e1ch<\/strong>:<\/p>\n
- \n
- Lo\u1ea1i<\/strong>: M\u1ed9t-\u0111\u1ebfn-nhi\u1ec1u (1:N)<\/li>\n
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i t\u00e1c gi\u1ea3 c\u00f3 th\u1ec3 vi\u1ebft nhi\u1ec1u s\u00e1ch, nh\u01b0ng m\u1ed7i s\u00e1ch ch\u1ec9 do m\u1ed9t t\u00e1c gi\u1ea3 vi\u1ebft.<\/li>\n<\/ul>\n<\/li>\n
- \n
Nh\u00e0 xu\u1ea5t b\u1ea3n \u0111\u1ebfn S\u00e1ch<\/strong>:<\/p>\n
- \n
- Lo\u1ea1i<\/strong>: M\u1ed9t-\u0111\u1ebfn-nhi\u1ec1u (1:N)<\/li>\n
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i nh\u00e0 xu\u1ea5t b\u1ea3n c\u00f3 th\u1ec3 xu\u1ea5t b\u1ea3n nhi\u1ec1u s\u00e1ch, nh\u01b0ng m\u1ed7i s\u00e1ch ch\u1ec9 do m\u1ed9t nh\u00e0 xu\u1ea5t b\u1ea3n ph\u00e1t h\u00e0nh.<\/li>\n<\/ul>\n<\/li>\n
- \n
Kh\u00e1ch h\u00e0ng \u0111\u1ebfn Gi\u1ecf h\u00e0ng<\/strong>:<\/p>\n
- \n
- Lo\u1ea1i<\/strong>: M\u1ed9t-\u0111\u1ebfn-nhi\u1ec1u (1:N)<\/li>\n
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i kh\u00e1ch h\u00e0ng c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u gi\u1ecf h\u00e0ng, nh\u01b0ng m\u1ed7i gi\u1ecf h\u00e0ng ch\u1ec9 thu\u1ed9c v\u1ec1 m\u1ed9t kh\u00e1ch h\u00e0ng.<\/li>\n<\/ul>\n<\/li>\n
- \n
Gi\u1ecf h\u00e0ng \u0111\u1ebfn S\u00e1ch<\/strong>:<\/p>\n
- \n
- Lo\u1ea1i<\/strong>: Nhi\u1ec1u-\u0111\u1ebfn-nhi\u1ec1u (M:N)<\/li>\n
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i gi\u1ecf h\u00e0ng c\u00f3 th\u1ec3 ch\u1ee9a nhi\u1ec1u s\u00e1ch, v\u00e0 m\u1ed7i s\u00e1ch c\u00f3 th\u1ec3 n\u1eb1m trong nhi\u1ec1u gi\u1ecf h\u00e0ng. M\u1ed1i quan h\u1ec7 n\u00e0y \u0111\u01b0\u1ee3c qu\u1ea3n l\u00fd b\u1edfi b\u1ea3ng\u00a0
ShoppingBasket_Book<\/code>\u00a0b\u1ea3ng.<\/li>\n<\/ul>\n<\/li>\n- \n
Kho h\u00e0ng \u0111\u1ebfn S\u00e1ch<\/strong>:<\/p>\n
- \n
- Lo\u1ea1i<\/strong>: Nhi\u1ec1u-\u0111\u1ebfn-nhi\u1ec1u (M:N)<\/li>\n
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i kho h\u00e0ng c\u00f3 th\u1ec3 l\u01b0u tr\u1eef nhi\u1ec1u s\u00e1ch, v\u00e0 m\u1ed7i s\u00e1ch c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong nhi\u1ec1u kho h\u00e0ng. M\u1ed1i quan h\u1ec7 n\u00e0y \u0111\u01b0\u1ee3c qu\u1ea3n l\u00fd b\u1edfi b\u1ea3ng\u00a0
Warehouse_Book<\/code>\u00a0b\u1ea3ng.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\nC\u00e1c kh\u00e1i ni\u1ec7m ch\u00ednh<\/h3>\n
- \n
- \n
Kh\u00f3a ch\u00ednh<\/strong>:<\/p>\n
- \n
- M\u1ed9t \u0111\u1ecbnh danh duy nh\u1ea5t cho m\u1ed9t b\u1ea3n ghi trong m\u1ed9t b\u1ea3ng. V\u00ed d\u1ee5,\u00a0
ISBN<\/code>\u00a0trong b\u1ea3ng\u00a0S\u00e1ch<\/code>\u00a0b\u1ea3ng v\u00e0\u00a0Email<\/code>\u00a0trong b\u1ea3ng\u00a0Kh\u00e1ch h\u00e0ng<\/code>\u00a0b\u1ea3ng.<\/li>\n<\/ul>\n<\/li>\n- \n
Kh\u00f3a ngo\u1ea1i<\/strong>:<\/p>\n
- \n
- M\u1ed9t tr\u01b0\u1eddng (ho\u1eb7c t\u1eadp h\u1ee3p c\u00e1c tr\u01b0\u1eddng) trong m\u1ed9t b\u1ea3ng x\u00e1c \u0111\u1ecbnh duy nh\u1ea5t m\u1ed9t h\u00e0ng c\u1ee7a b\u1ea3ng kh\u00e1c. V\u00ed d\u1ee5,\u00a0
BookISBN<\/code>\u00a0trong b\u1ea3ng\u00a0ShoppingBasket_Book<\/code>\u00a0b\u1ea3ng tham chi\u1ebfu \u0111\u1ebfn\u00a0ISBN<\/code>\u00a0trong\u00a0S\u00e1ch<\/code>\u00a0b\u1ea3ng.<\/li>\n<\/ul>\n<\/li>\n- \n
M\u1ed1i quan h\u1ec7 nhi\u1ec1u-\u0111a<\/strong>:<\/p>\n
- \n
- M\u1ed9t m\u1ed1i quan h\u1ec7 m\u00e0 m\u1ed7i th\u1ef1c th\u1ec3 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c li\u00ean k\u1ebft v\u1edbi nhi\u1ec1u th\u1ef1c th\u1ec3 kh\u00e1c, v\u00e0 ng\u01b0\u1ee3c l\u1ea1i. M\u1ed1i quan h\u1ec7 n\u00e0y th\u01b0\u1eddng \u0111\u01b0\u1ee3c qu\u1ea3n l\u00fd b\u1eb1ng b\u1ea3ng li\u00ean k\u1ebft. V\u00ed d\u1ee5, b\u1ea3ng\u00a0
ShoppingBasket_Book<\/code>\u00a0b\u1ea3ng qu\u1ea3n l\u00fd m\u1ed1i quan h\u1ec7 nhi\u1ec1u-\u0111a gi\u1eefa\u00a0ShoppingBasket<\/code>\u00a0v\u00e0\u00a0S\u00e1ch<\/code>.<\/li>\n<\/ul>\n<\/li>\n- \n
M\u1ed1i quan h\u1ec7 m\u1ed9t-\u0111a<\/strong>:<\/p>\n
- \n
- M\u1ed9t m\u1ed1i quan h\u1ec7 m\u00e0 m\u1ed7i th\u1ef1c th\u1ec3 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c li\u00ean k\u1ebft v\u1edbi nhi\u1ec1u th\u1ef1c th\u1ec3 kh\u00e1c, nh\u01b0ng ng\u01b0\u1ee3c l\u1ea1i th\u00ec kh\u00f4ng. V\u00ed d\u1ee5, m\u1ed7i t\u00e1c gi\u1ea3 c\u00f3 th\u1ec3 vi\u1ebft nhi\u1ec1u s\u00e1ch, nh\u01b0ng m\u1ed7i s\u00e1ch ch\u1ec9 do m\u1ed9t t\u00e1c gi\u1ea3 vi\u1ebft.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n
T\u1ea1o s\u01a1 \u0111\u1ed3 ERD b\u1eb1ng Visual Paradigm<\/h3>\n
Visual Paradigm l\u00e0 m\u1ed9t b\u1ed9 ph\u1ea7n m\u1ec1m to\u00e0n di\u1ec7n h\u1ed7 tr\u1ee3 vi\u1ec7c t\u1ea1o v\u00e0 qu\u1ea3n l\u00fd s\u01a1 \u0111\u1ed3 ERD. N\u00f3 cung c\u1ea5p nhi\u1ec1u t\u00ednh n\u0103ng gi\u00fap m\u00f4 h\u00ecnh h\u00f3a c\u01a1 s\u1edf d\u1eef li\u1ec7u hi\u1ec7u qu\u1ea3 v\u00e0 hi\u1ec7u su\u1ea5t cao.<\/p>\n
C\u00e1c t\u00ednh n\u0103ng ch\u00ednh c\u1ee7a Visual Paradigm cho ERD<\/h3>\n
- \n
- T\u1ea1o s\u01a1 \u0111\u1ed3 ERD<\/strong>: Visual Paradigm cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng d\u1ec5 d\u00e0ng t\u1ea1o s\u01a1 \u0111\u1ed3 ERD, bao g\u1ed3m c\u00e1c th\u1ef1c th\u1ec3, thu\u1ed9c t\u00ednh v\u00e0 m\u1ed1i quan h\u1ec7. N\u00f3 h\u1ed7 tr\u1ee3 nhi\u1ec1u lo\u1ea1i m\u1ed1i quan h\u1ec7, ch\u1eb3ng h\u1ea1n nh\u01b0 m\u1ed9t-\u0111\u01a1n, m\u1ed9t-\u0111a v\u00e0 nhi\u1ec1u-\u0111a.<\/li>\n
- T\u1ea1o t\u00e0i li\u1ec7u m\u00f4 t\u1ea3 d\u1eef li\u1ec7u<\/strong>: Ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 t\u1ea1o t\u00e0i li\u1ec7u m\u00f4 t\u1ea3 d\u1eef li\u1ec7u t\u1eeb c\u00e1c m\u00f4 h\u00ecnh ERD c\u1ee7a m\u00ecnh, c\u00f3 th\u1ec3 chia s\u1ebb v\u1edbi c\u00e1c b\u00ean li\u00ean quan. T\u00ednh n\u0103ng n\u00e0y gi\u00fap ghi ch\u00e9p thi\u1ebft k\u1ebf c\u01a1 s\u1edf d\u1eef li\u1ec7u v\u00e0 truy\u1ec1n \u0111\u1ea1t th\u00f4ng tin m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3.<\/li>\n
- T\u1ea1o c\u01a1 s\u1edf d\u1eef li\u1ec7u<\/strong>: Visual Paradigm cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng t\u1ea1o c\u01a1 s\u1edf d\u1eef li\u1ec7u tr\u1ef1c ti\u1ebfp t\u1eeb c\u00e1c m\u00f4 h\u00ecnh ERD. Bao g\u1ed3m vi\u1ec7c t\u1ea1o c\u00e1c t\u1eadp l\u1ec7nh SQL (DDL) \u0111\u1ec3 t\u1ea1o c\u1ea5u tr\u00fac c\u01a1 s\u1edf d\u1eef li\u1ec7u v\u00e0 th\u1ef1c thi ch\u00fang \u0111\u1ec3 thi\u1ebft l\u1eadp c\u01a1 s\u1edf d\u1eef li\u1ec7u.<\/li>\n
- Ph\u00e2n t\u00edch ng\u01b0\u1ee3c<\/strong>: Ph\u1ea7n m\u1ec1m h\u1ed7 tr\u1ee3 ph\u00e2n t\u00edch ng\u01b0\u1ee3c, cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng t\u1ea1o s\u01a1 \u0111\u1ed3 ERD t\u1eeb c\u00e1c c\u01a1 s\u1edf d\u1eef li\u1ec7u hi\u1ec7n c\u00f3. T\u00ednh n\u0103ng n\u00e0y h\u1eefu \u00edch trong vi\u1ec7c ph\u00e2n t\u00edch v\u00e0 ghi ch\u00e9p c\u1ea5u tr\u00fac c\u01a1 s\u1edf d\u1eef li\u1ec7u hi\u1ec7n t\u1ea1i.<\/li>\n<\/ol>\n
C\u00e1c lo\u1ea1i m\u00f4 h\u00ecnh ERD trong Visual Paradigm<\/h3>\n
- \n
- S\u01a1 \u0111\u1ed3 ERD kh\u00e1i ni\u1ec7m<\/strong>: T\u1eadp trung v\u00e0o c\u00e1c y\u00eau c\u1ea7u kinh doanh m\u00e0 kh\u00f4ng c\u1ea7n xem x\u00e9t chi ti\u1ebft tri\u1ec3n khai c\u01a1 s\u1edf d\u1eef li\u1ec7u. N\u00f3 h\u1ed7 tr\u1ee3 c\u00e1c m\u1ed1i quan h\u1ec7 t\u1ed5ng qu\u00e1t h\u00f3a.<\/li>\n
- T\u1ea1o t\u00e0i li\u1ec7u m\u00f4 t\u1ea3 d\u1eef li\u1ec7u<\/strong>: Ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 t\u1ea1o t\u00e0i li\u1ec7u m\u00f4 t\u1ea3 d\u1eef li\u1ec7u t\u1eeb c\u00e1c m\u00f4 h\u00ecnh ERD c\u1ee7a m\u00ecnh, c\u00f3 th\u1ec3 chia s\u1ebb v\u1edbi c\u00e1c b\u00ean li\u00ean quan. T\u00ednh n\u0103ng n\u00e0y gi\u00fap ghi ch\u00e9p thi\u1ebft k\u1ebf c\u01a1 s\u1edf d\u1eef li\u1ec7u v\u00e0 truy\u1ec1n \u0111\u1ea1t th\u00f4ng tin m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3.<\/li>\n
- T\u1ea1o s\u01a1 \u0111\u1ed3 ERD<\/strong>: Visual Paradigm cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng d\u1ec5 d\u00e0ng t\u1ea1o s\u01a1 \u0111\u1ed3 ERD, bao g\u1ed3m c\u00e1c th\u1ef1c th\u1ec3, thu\u1ed9c t\u00ednh v\u00e0 m\u1ed1i quan h\u1ec7. N\u00f3 h\u1ed7 tr\u1ee3 nhi\u1ec1u lo\u1ea1i m\u1ed1i quan h\u1ec7, ch\u1eb3ng h\u1ea1n nh\u01b0 m\u1ed9t-\u0111\u01a1n, m\u1ed9t-\u0111a v\u00e0 nhi\u1ec1u-\u0111a.<\/li>\n
- \n
- \n
- \n
- M\u1ed9t \u0111\u1ecbnh danh duy nh\u1ea5t cho m\u1ed9t b\u1ea3n ghi trong m\u1ed9t b\u1ea3ng. V\u00ed d\u1ee5,\u00a0
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i kho h\u00e0ng c\u00f3 th\u1ec3 l\u01b0u tr\u1eef nhi\u1ec1u s\u00e1ch, v\u00e0 m\u1ed7i s\u00e1ch c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong nhi\u1ec1u kho h\u00e0ng. M\u1ed1i quan h\u1ec7 n\u00e0y \u0111\u01b0\u1ee3c qu\u1ea3n l\u00fd b\u1edfi b\u1ea3ng\u00a0
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i gi\u1ecf h\u00e0ng c\u00f3 th\u1ec3 ch\u1ee9a nhi\u1ec1u s\u00e1ch, v\u00e0 m\u1ed7i s\u00e1ch c\u00f3 th\u1ec3 n\u1eb1m trong nhi\u1ec1u gi\u1ecf h\u00e0ng. M\u1ed1i quan h\u1ec7 n\u00e0y \u0111\u01b0\u1ee3c qu\u1ea3n l\u00fd b\u1edfi b\u1ea3ng\u00a0
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i kh\u00e1ch h\u00e0ng c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u gi\u1ecf h\u00e0ng, nh\u01b0ng m\u1ed7i gi\u1ecf h\u00e0ng ch\u1ec9 thu\u1ed9c v\u1ec1 m\u1ed9t kh\u00e1ch h\u00e0ng.<\/li>\n<\/ul>\n<\/li>\n
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i nh\u00e0 xu\u1ea5t b\u1ea3n c\u00f3 th\u1ec3 xu\u1ea5t b\u1ea3n nhi\u1ec1u s\u00e1ch, nh\u01b0ng m\u1ed7i s\u00e1ch ch\u1ec9 do m\u1ed9t nh\u00e0 xu\u1ea5t b\u1ea3n ph\u00e1t h\u00e0nh.<\/li>\n<\/ul>\n<\/li>\n
- M\u00f4 t\u1ea3<\/strong>: M\u1ed7i t\u00e1c gi\u1ea3 c\u00f3 th\u1ec3 vi\u1ebft nhi\u1ec1u s\u00e1ch, nh\u01b0ng m\u1ed7i s\u00e1ch ch\u1ec9 do m\u1ed9t t\u00e1c gi\u1ea3 vi\u1ebft.<\/li>\n<\/ul>\n<\/li>\n
- Lo\u1ea1i<\/strong>: M\u1ed9t-\u0111\u1ebfn-nhi\u1ec1u (1:N)<\/li>\n
- Thu\u1ed9c t\u00ednh<\/strong>:\n
- \n
- T\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u<\/strong>: B\u1eb1ng c\u00e1ch x\u00e1c \u0111\u1ecbnh c\u00e1c m\u1ed1i quan h\u1ec7 v\u00e0 kh\u00f3a, ERD gi\u00fap \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n v\u00e0 t\u00ednh nh\u1ea5t qu\u00e1n c\u1ee7a d\u1eef li\u1ec7u.<\/li>\n
- Kh\u00f3a ngo\u1ea1i<\/strong>: M\u1ed9t thu\u1ed9c t\u00ednh trong m\u1ed9t th\u1ef1c th\u1ec3 l\u00e0 kh\u00f3a ch\u00ednh trong th\u1ef1c th\u1ec3 kh\u00e1c, t\u1ea1o ra m\u1ed1i quan h\u1ec7 gi\u1eefa hai th\u1ef1c th\u1ec3.<\/li>\n<\/ol>\n