{"id":9088,"date":"2025-03-25T16:50:59","date_gmt":"2025-03-25T09:50:59","guid":{"rendered":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/?p=9088"},"modified":"2026-08-05T10:19:55","modified_gmt":"2026-08-05T03:19:55","slug":"database-schema-la-gi","status":"publish","type":"post","link":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/tu-van-nghe-nghiep\/database-schema-la-gi","title":{"rendered":"Database schema l\u00e0 g\u00ec? Kh\u00e1m ph\u00e1 t\u1ea7m quan tr\u1ecdng trong qu\u1ea3n l\u00fd d\u1eef li\u1ec7u"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong>Database schema l\u00e0 g\u00ec?<\/strong> \u0110\u00e2y l\u00e0 m\u1ed9t c\u00e2u h\u1ecfi quan tr\u1ecdng trong l\u0129nh v\u1ef1c qu\u1ea3n l\u00fd d\u1eef li\u1ec7u v\u00e0 h\u1ec7 th\u1ed1ng th\u00f4ng tin. Khi b\u1ea1n h\u1ecdc v\u1ec1 c\u01a1 s\u1edf d\u1eef li\u1ec7u, vi\u1ec7c n\u1eafm r\u00f5 kh\u00e1i ni\u1ec7m n\u00e0y s\u1ebd gi\u00fap b\u1ea1n thi\u1ebft k\u1ebf v\u00e0 t\u1ed1i \u01b0u h\u00f3a c\u1ea5u tr\u00fac d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3 h\u01a1n. Trong b\u00e0i vi\u1ebft n\u00e0y, ch\u00fang ta s\u1ebd c\u00f9ng nhau kh\u00e1m ph\u00e1 chi ti\u1ebft v\u1ec1 database schema, t\u1eeb \u0111\u1ecbnh ngh\u0129a \u0111\u1ebfn l\u1ee3i \u00edch, c\u00e1ch t\u1ea1o ra v\u00e0 nh\u1eefng \u0111i\u1ec1u c\u1ea7n l\u01b0u \u00fd khi thi\u1ebft k\u1ebf n\u00f3.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"512\" height=\"512\" src=\"https:\/\/cl-wpml.careerlink.vn\/cam-nang-viec-lam\/wp-content\/uploads\/2025\/03\/25162110\/Database-schema-la-gi.png\" alt=\"Database-schema-la-gi.png\" class=\"wp-image-9111\" srcset=\"https:\/\/cl-wpml.careerlink.vn\/cam-nang-viec-lam\/wp-content\/uploads\/2025\/03\/25162110\/Database-schema-la-gi.png 512w, https:\/\/cl-wpml.careerlink.vn\/cam-nang-viec-lam\/wp-content\/uploads\/2025\/03\/25162110\/Database-schema-la-gi-300x300.png 300w, https:\/\/cl-wpml.careerlink.vn\/cam-nang-viec-lam\/wp-content\/uploads\/2025\/03\/25162110\/Database-schema-la-gi-150x150.png 150w\" sizes=\"auto, (max-width: 512px) 100vw, 512px\" \/><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading\"><strong>Database schema (L\u01b0\u1ee3c \u0111\u1ed3 CSDL) l\u00e0 g\u00ec?<\/strong><\/h2>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">\u0110\u1ec3 hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 kh\u00e1i ni\u1ec7m <strong>database schema<\/strong>, tr\u01b0\u1edbc ti\u00ean ch\u00fang ta c\u1ea7n x\u00e1c \u0111\u1ecbnh m\u1ed9t s\u1ed1 thu\u1eadt ng\u1eef li\u00ean quan. L\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u l\u00e0 m\u1ed9t m\u00f4 t\u1ea3 t\u1ed5ng qu\u00e1t v\u1ec1 c\u1ea5u tr\u00fac c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u, bao g\u1ed3m c\u00e1c b\u1ea3ng, m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c b\u1ea3ng, ki\u1ec3u d\u1eef li\u1ec7u v\u00e0 c\u00e1c r\u00e0ng bu\u1ed9c kh\u00e1c. N\u00f3 \u0111\u00f3ng vai tr\u00f2 nh\u01b0 m\u1ed9t b\u1ea3n \u0111\u1ed3 h\u01b0\u1edbng d\u1eabn cho c\u00e1ch m\u00e0 d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c t\u1ed5 ch\u1ee9c v\u00e0 l\u01b0u tr\u1eef trong h\u1ec7 th\u1ed1ng.<\/p>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u0110\u1ecbnh ngh\u0129a c\u01a1 b\u1ea3n<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Schema SQL l\u00e0 g\u00ec<\/strong>? Schema trong SQL th\u01b0\u1eddng \u0111\u01b0\u1ee3c hi\u1ec3u l\u00e0 m\u1ed9t t\u1eadp h\u1ee3p c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng trong c\u01a1 s\u1edf d\u1eef li\u1ec7u nh\u01b0 b\u1ea3ng, ch\u1ec9 m\u1ee5c, quan h\u1ec7 v\u00e0 c\u00e1c quy t\u1eafc kh\u00e1c. N\u00f3 cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u theo c\u00e1c c\u00e1ch th\u1ee9c kh\u00e1c nhau \u0111\u1ec3 d\u1ec5 d\u00e0ng qu\u1ea3n l\u00fd v\u00e0 truy v\u1ea5n.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u1eb1ng c\u00e1ch s\u1eed d\u1ee5ng <strong>schema trong SQL<\/strong>, ng\u01b0\u1eddi ph\u00e1t tri\u1ec3n c\u00f3 th\u1ec3 \u0111\u1ecbnh ngh\u0129a c\u00e1c b\u1ea3ng v\u1edbi c\u00e1c ki\u1ec3u d\u1eef li\u1ec7u kh\u00e1c nhau v\u00e0 ch\u1ec9 \u0111\u1ecbnh c\u00e1c m\u1ed1i quan h\u1ec7 gi\u1eefa ch\u00fang. \u0110i\u1ec1u n\u00e0y kh\u00f4ng ch\u1ec9 gi\u00fap ng\u0103n ng\u1eeba s\u1ef1 tr\u00f9ng l\u1eb7p d\u1eef li\u1ec7u m\u00e0 c\u00f2n t\u1ed1i \u01b0u h\u00f3a kh\u1ea3 n\u0103ng truy xu\u1ea5t th\u00f4ng tin.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>C\u00e1c th\u00e0nh ph\u1ea7n ch\u00ednh c\u1ee7a database schema<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u c\u00f3 th\u1ec3 bao g\u1ed3m nhi\u1ec1u th\u00e0nh ph\u1ea7n kh\u00e1c nhau, ch\u1eb3ng h\u1ea1n nh\u01b0:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>B\u1ea3ng (Tables)<\/strong>: L\u00e0 n\u01a1i ch\u1ee9a d\u1eef li\u1ec7u th\u1ef1c t\u1ebf. M\u1ed7i b\u1ea3ng c\u00f3 c\u00e1c c\u1ed9t v\u00e0 h\u00e0ng t\u01b0\u01a1ng \u1ee9ng.<\/li>\n\n\n\n<li><strong>Ch\u1ec9 m\u1ee5c (Indexes)<\/strong>: Gi\u00fap t\u0103ng t\u1ed1c \u0111\u1ed9 t\u00ecm ki\u1ebfm v\u00e0 truy v\u1ea5n d\u1eef li\u1ec7u.<\/li>\n\n\n\n<li><strong>R\u00e0ng bu\u1ed9c (Constraints)<\/strong>: L\u00e0 c\u00e1c quy t\u1eafc \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng \u0111\u1ec3 b\u1ea3o \u0111\u1ea3m t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u, ch\u1eb3ng h\u1ea1n nh\u01b0 r\u00e0ng bu\u1ed9c kh\u00f3a ch\u00ednh v\u00e0 kh\u00f3a ngo\u1ea1i.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1ed7i th\u00e0nh ph\u1ea7n n\u00e0y \u0111\u1ec1u c\u00f3 vai tr\u00f2 ri\u00eang trong vi\u1ec7c x\u00e1c \u0111\u1ecbnh c\u00e1ch m\u00e0 d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef v\u00e0 truy c\u1eadp.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>T\u1ea1i sao database schema quan tr\u1ecdng?<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">L\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u gi\u00fap cho ng\u01b0\u1eddi qu\u1ea3n l\u00fd d\u1eef li\u1ec7u d\u1ec5 d\u00e0ng h\u00ecnh dung v\u00e0 qu\u1ea3n l\u00fd c\u1ea5u tr\u00fac c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u. N\u00f3 c\u0169ng h\u1ed7 tr\u1ee3 trong vi\u1ec7c duy tr\u00ec t\u00ednh nh\u1ea5t qu\u00e1n v\u00e0 ch\u00ednh x\u00e1c c\u1ee7a d\u1eef li\u1ec7u. H\u01a1n n\u1eefa, m\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 thi\u1ebft k\u1ebf t\u1ed1t c\u00f2n g\u00f3p ph\u1ea7n gi\u1ea3m thi\u1ec3u th\u1eddi gian v\u00e0 c\u00f4ng s\u1ee9c khi ph\u00e1t tri\u1ec3n \u1ee9ng d\u1ee5ng, b\u1edfi v\u00ec n\u00f3 \u0111\u00e3 x\u00e1c \u0111\u1ecbnh s\u1eb5n c\u00e1ch m\u00e0 d\u1eef li\u1ec7u s\u1ebd \u0111\u01b0\u1ee3c t\u1ed5 ch\u1ee9c.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Nh\u1eefng l\u1ee3i \u00edch khi s\u1eed d\u1ee5ng database schema<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Khi thi\u1ebft k\u1ebf m\u1ed9t h\u1ec7 th\u1ed1ng c\u01a1 s\u1edf d\u1eef li\u1ec7u, vi\u1ec7c \u00e1p d\u1ee5ng m\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u c\u00f3 th\u1ec3 mang l\u1ea1i r\u1ea5t nhi\u1ec1u l\u1ee3i \u00edch. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 \u0111i\u1ec3m n\u1ed5i b\u1eadt m\u00e0 ch\u00fang ta c\u1ea7n xem x\u00e9t.<\/p>\n<p>Tr\u00ean th\u1ecb tr\u01b0\u1eddng lao \u0111\u1ed9ng, chuy\u00ean m\u1ee5c CNTT ph\u1ea7n m\u1ec1m c\u1ee7a CareerLink hi\u1ec7n \u0111\u0103ng kho\u1ea3ng 438 tin tuy\u1ec3n d\u1ee5ng, m\u1ee9c l\u01b0\u01a1ng ph\u1ed5 bi\u1ebfn dao \u0111\u1ed9ng 8-130 tri\u1ec7u \u0111\u1ed3ng m\u1ed7i th\u00e1ng t\u00f9y c\u1ea5p b\u1eadc v\u00e0 kinh nghi\u1ec7m. Danh s\u00e1ch <a href=\"https:\/\/www.careerlink.vn\/viec-lam\/cntt-phan-mem\/19\" style=\"color:#1565c0;font-weight:600\">vi\u1ec7c l\u00e0m ng\u00e0nh CNTT ph\u1ea7n m\u1ec1m<\/a> l\u00e0 ngu\u1ed3n tham kh\u1ea3o h\u1eefu \u00edch \u0111\u1ec3 \u0111\u1ed1i chi\u1ebfu k\u1ef3 v\u1ecdng c\u1ee7a nh\u00e0 tuy\u1ec3n d\u1ee5ng v\u1edbi n\u0103ng l\u1ef1c b\u1ea3n th\u00e2n.<\/p>\n\n\n\n\n<h3 class=\"wp-block-heading\"><strong>T\u00ednh t\u1ed5 ch\u1ee9c v\u00e0 d\u1ec5 qu\u1ea3n l\u00fd<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1eed d\u1ee5ng <strong>database schema<\/strong> gi\u00fap t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch logic v\u00e0 c\u00f3 h\u1ec7 th\u1ed1ng. Nh\u1edd v\u00e0o vi\u1ec7c ph\u00e2n lo\u1ea1i d\u1eef li\u1ec7u trong c\u00e1c b\u1ea3ng v\u00e0 m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c b\u1ea3ng, ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 d\u1ec5 d\u00e0ng t\u00ecm ki\u1ebfm, truy v\u1ea5n v\u00e0 c\u1eadp nh\u1eadt th\u00f4ng tin m\u00e0 kh\u00f4ng g\u1eb7p ph\u1ea3i kh\u00f3 kh\u0103n.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110i\u1ec1u n\u00e0y \u0111\u1eb7c bi\u1ec7t quan tr\u1ecdng trong c\u00e1c \u1ee9ng d\u1ee5ng l\u1edbn, n\u01a1i m\u00e0 d\u1eef li\u1ec7u c\u00f3 th\u1ec3 b\u1ecb ph\u00e2n m\u1ea3nh ho\u1eb7c tr\u1edf n\u00ean ph\u1ee9c t\u1ea1p. M\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 r\u00f5 r\u00e0ng gi\u00fap \u0111\u1ea3m b\u1ea3o r\u1eb1ng m\u1ecdi ng\u01b0\u1eddi trong nh\u00f3m ph\u00e1t tri\u1ec3n \u0111\u1ec1u hi\u1ec3u c\u1ea5u tr\u00fac d\u1eef li\u1ec7u v\u00e0 c\u00f3 th\u1ec3 l\u00e0m vi\u1ec7c m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>T\u0103ng c\u01b0\u1eddng hi\u1ec7u su\u1ea5t<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1ed9t l\u1ee3i \u00edch kh\u00e1c c\u1ee7a <strong>schema trong database<\/strong> l\u00e0 kh\u1ea3 n\u0103ng c\u1ea3i thi\u1ec7n hi\u1ec7u su\u1ea5t c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u. B\u1eb1ng c\u00e1ch t\u1ed1i \u01b0u h\u00f3a c\u1ea5u tr\u00fac d\u1eef li\u1ec7u v\u00e0 s\u1eed d\u1ee5ng ch\u1ec9 m\u1ee5c m\u1ed9t c\u00e1ch h\u1ee3p l\u00fd, h\u1ec7 th\u1ed1ng c\u00f3 th\u1ec3 truy xu\u1ea5t th\u00f4ng tin nhanh h\u01a1n r\u1ea5t nhi\u1ec1u.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">H\u01a1n n\u1eefa, vi\u1ec7c t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch h\u1ee3p l\u00fd gi\u00fap gi\u1ea3m thi\u1ec3u t\u00ecnh tr\u1ea1ng tr\u00f9ng l\u1eb7p, t\u1eeb \u0111\u00f3 ti\u1ebft ki\u1ec7m kh\u00f4ng gian l\u01b0u tr\u1eef v\u00e0 c\u1ea3i thi\u1ec7n t\u1ed1c \u0111\u1ed9 x\u1eed l\u00fd d\u1eef li\u1ec7u.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>H\u1ed7 tr\u1ee3 t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">T\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u l\u00e0 m\u1ed9t y\u1ebfu t\u1ed1 quan tr\u1ecdng trong b\u1ea5t k\u1ef3 h\u1ec7 th\u1ed1ng c\u01a1 s\u1edf d\u1eef li\u1ec7u n\u00e0o. S\u1eed d\u1ee5ng <strong>schema sql la g\u00ec?<\/strong> gi\u00fap \u0111\u1eb7t ra c\u00e1c r\u00e0ng bu\u1ed9c v\u00e0 quy t\u1eafc c\u1ea7n thi\u1ebft \u0111\u1ec3 b\u1ea3o \u0111\u1ea3m r\u1eb1ng d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c nh\u1eadp v\u00e0o h\u1ec7 th\u1ed1ng lu\u00f4n ch\u00ednh x\u00e1c v\u00e0 \u0111\u00e1ng tin c\u1eady.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c r\u00e0ng bu\u1ed9c nh\u01b0 kh\u00f3a ch\u00ednh v\u00e0 kh\u00f3a ngo\u1ea1i gi\u00fap ki\u1ec3m so\u00e1t m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c b\u1ea3ng, ng\u0103n ch\u1eb7n s\u1ef1 xu\u1ea5t hi\u1ec7n c\u1ee7a d\u1eef li\u1ec7u kh\u00f4ng h\u1ee3p l\u1ec7. \u0110i\u1ec1u n\u00e0y c\u1ef1c k\u1ef3 quan tr\u1ecdng trong c\u00e1c \u1ee9ng d\u1ee5ng y\u00eau c\u1ea7u \u0111\u1ed9 ch\u00ednh x\u00e1c v\u00e0 t\u00ednh nh\u1ea5t qu\u00e1n cao.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>C\u00e1c lo\u1ea1i database schema c\u01a1 b\u1ea3n<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Trong th\u1ebf gi\u1edbi c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u, c\u00f3 nhi\u1ec1u lo\u1ea1i l\u01b0\u1ee3c \u0111\u1ed3 kh\u00e1c nhau, t\u00f9y thu\u1ed9c v\u00e0o c\u00e1ch m\u00e0 d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c t\u1ed5 ch\u1ee9c v\u00e0 s\u1eed d\u1ee5ng. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 lo\u1ea1i c\u01a1 b\u1ea3n m\u00e0 b\u1ea1n n\u00ean bi\u1ebft.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Logical schema<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Logical schema<\/strong> l\u00e0 m\u00f4 h\u00ecnh l\u00fd thuy\u1ebft c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u, n\u01a1i m\u00e0 c\u00e1c thu\u1ed9c t\u00ednh v\u00e0 m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c b\u1ea3ng \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh m\u00e0 kh\u00f4ng c\u1ea7n quan t\u00e2m \u0111\u1ebfn c\u00e1ch m\u00e0 ch\u00fang s\u1ebd \u0111\u01b0\u1ee3c tri\u1ec3n khai v\u1eadt l\u00fd. \u0110\u00e2y l\u00e0 b\u01b0\u1edbc \u0111\u1ea7u ti\u00ean trong qu\u00e1 tr\u00ecnh thi\u1ebft k\u1ebf c\u01a1 s\u1edf d\u1eef li\u1ec7u.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Logical schema gi\u00fap cho ng\u01b0\u1eddi thi\u1ebft k\u1ebf c\u00f3 \u0111\u01b0\u1ee3c c\u00e1i nh\u00ecn t\u1ed5ng quan v\u1ec1 c\u1ea5u tr\u00fac c\u01a1 s\u1edf d\u1eef li\u1ec7u m\u00e0 kh\u00f4ng b\u1ecb \u1ea3nh h\u01b0\u1edfng b\u1edfi c\u00e1c y\u1ebfu t\u1ed1 k\u1ef9 thu\u1eadt. \u0110i\u1ec1u n\u00e0y cho ph\u00e9p h\u1ecd t\u1eadp trung v\u00e0o vi\u1ec7c x\u00e1c \u0111\u1ecbnh c\u00e1c y\u00eau c\u1ea7u kinh doanh v\u00e0 c\u00e1ch m\u00e0 d\u1eef li\u1ec7u c\u1ea7n \u0111\u01b0\u1ee3c t\u1ed5 ch\u1ee9c \u0111\u1ec3 ph\u1ee5c v\u1ee5 cho nh\u1eefng y\u00eau c\u1ea7u \u0111\u00f3.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Physical schema<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Physical schema<\/strong> l\u00e0 phi\u00ean b\u1ea3n c\u1ee5 th\u1ec3 v\u00e0 chi ti\u1ebft h\u01a1n c\u1ee7a logical schema. N\u00f3 x\u00e1c \u0111\u1ecbnh c\u00e1ch m\u00e0 d\u1eef li\u1ec7u s\u1ebd \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef tr\u00ean c\u00e1c thi\u1ebft b\u1ecb v\u1eadt l\u00fd, bao g\u1ed3m c\u00e1c \u0111\u1ecbnh d\u1ea1ng t\u1ec7p, \u0111\u01b0\u1eddng d\u1eabn l\u01b0u tr\u1eef v\u00e0 c\u00e1ch th\u1ee9c t\u1ed1i \u01b0u h\u00f3a hi\u1ec7u su\u1ea5t.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Khi chuy\u1ec3n t\u1eeb logical schema sang physical schema, c\u00e1c nh\u00e0 ph\u00e1t tri\u1ec3n s\u1ebd c\u1ea7n xem x\u00e9t nhi\u1ec1u y\u1ebfu t\u1ed1 nh\u01b0 t\u1ed1c \u0111\u1ed9 truy xu\u1ea5t d\u1eef li\u1ec7u, kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng v\u00e0 t\u00ednh linh ho\u1ea1t c\u1ee7a h\u1ec7 th\u1ed1ng. \u0110\u00e2y l\u00e0 b\u01b0\u1edbc quan tr\u1ecdng \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng c\u01a1 s\u1edf d\u1eef li\u1ec7u kh\u00f4ng ch\u1ec9 ho\u1ea1t \u0111\u1ed9ng t\u1ed1t m\u00e0 c\u00f2n c\u00f3 th\u1ec3 \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c nhu c\u1ea7u trong t\u01b0\u01a1ng lai.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-wp-embed is-provider-c-m-nang-vi-c-l-m wp-block-embed-c-m-nang-vi-c-l-m\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"1DQwTpB61Z\"><a href=\"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/tim-viec\/top-10-cac-nganh-nghe-hot-hien-nay\">TOP 10 C\u00e1c Ng\u00e0nh Ngh\u1ec1 HOT Hi\u1ec7n Nay &#8211; \u0110\u1ecbnh H\u01b0\u1edbng T\u01b0\u01a1ng Lai<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; visibility: hidden;\" title=\"&#8220;TOP 10 C\u00e1c Ng\u00e0nh Ngh\u1ec1 HOT Hi\u1ec7n Nay &#8211; \u0110\u1ecbnh H\u01b0\u1edbng T\u01b0\u01a1ng Lai&#8221; &#8212; C\u1ea9m Nang Vi\u1ec7c L\u00e0m\" src=\"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/tim-viec\/top-10-cac-nganh-nghe-hot-hien-nay\/embed#?secret=tiUMhYxwgA#?secret=1DQwTpB61Z\" data-secret=\"1DQwTpB61Z\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>External schema<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>External schema<\/strong> \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u1ecbnh ngh\u0129a c\u00e1ch m\u00e0 ng\u01b0\u1eddi d\u00f9ng cu\u1ed1i s\u1ebd t\u01b0\u01a1ng t\u00e1c v\u1edbi d\u1eef li\u1ec7u. \u0110i\u1ec1u n\u00e0y bao g\u1ed3m vi\u1ec7c x\u00e1c \u0111\u1ecbnh c\u00e1c giao di\u1ec7n, b\u00e1o c\u00e1o v\u00e0 c\u00e1c c\u00f4ng c\u1ee5 m\u00e0 ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng \u0111\u1ec3 truy xu\u1ea5t v\u00e0 ph\u00e2n t\u00edch d\u1eef li\u1ec7u.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1ee5c \u0111\u00edch c\u1ee7a external schema l\u00e0 cung c\u1ea5p tr\u1ea3i nghi\u1ec7m t\u1ed1t nh\u1ea5t cho ng\u01b0\u1eddi d\u00f9ng cu\u1ed1i, \u0111\u1ed3ng th\u1eddi v\u1eabn duy tr\u00ec t\u00ednh to\u00e0n v\u1eb9n v\u00e0 b\u1ea3o m\u1eadt c\u1ee7a d\u1eef li\u1ec7u. Vi\u1ec7c thi\u1ebft k\u1ebf external schema h\u1ee3p l\u00fd s\u1ebd gi\u00fap ng\u01b0\u1eddi d\u00f9ng d\u1ec5 d\u00e0ng h\u01a1n trong vi\u1ec7c t\u00ecm ki\u1ebfm v\u00e0 s\u1eed d\u1ee5ng th\u00f4ng tin.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>C\u00e1ch t\u1ea1o m\u1ed9t database schema<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Vi\u1ec7c t\u1ea1o ra m\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t nhi\u1ec7m v\u1ee5 \u0111\u01a1n gi\u1ea3n, nh\u01b0ng n\u1ebfu b\u1ea1n tu\u00e2n th\u1ee7 \u0111\u00fang quy tr\u00ecnh, b\u1ea1n c\u00f3 th\u1ec3 thi\u1ebft l\u1eadp m\u1ed9t c\u01a1 s\u1edf d\u1eef li\u1ec7u hi\u1ec7u qu\u1ea3 v\u00e0 d\u1ec5 qu\u1ea3n l\u00fd. Sau \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 b\u01b0\u1edbc c\u1ea7n thi\u1ebft trong qu\u00e1 tr\u00ecnh n\u00e0y.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>X\u00e1c \u0111\u1ecbnh y\u00eau c\u1ea7u<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Tr\u01b0\u1edbc ti\u00ean, b\u1ea1n c\u1ea7n x\u00e1c \u0111\u1ecbnh r\u00f5 y\u00eau c\u1ea7u c\u1ee7a d\u1ef1 \u00e1n. B\u1ea1n c\u1ea7n bi\u1ebft lo\u1ea1i d\u1eef li\u1ec7u n\u00e0o s\u1ebd \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef, ai s\u1ebd s\u1eed d\u1ee5ng c\u01a1 s\u1edf d\u1eef li\u1ec7u v\u00e0 c\u00e1ch m\u00e0 d\u1eef li\u1ec7u s\u1ebd \u0111\u01b0\u1ee3c truy c\u1eadp v\u00e0 thao t\u00e1c. \u0110i\u1ec1u n\u00e0y s\u1ebd gi\u00fap b\u1ea1n c\u00f3 c\u01a1 s\u1edf \u0111\u1ec3 x\u00e2y d\u1ef1ng l\u01b0\u1ee3c \u0111\u1ed3 ph\u00f9 h\u1ee3p.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u1ea1n c\u00f3 th\u1ec3 ti\u1ebfn h\u00e0nh ph\u1ecfng v\u1ea5n ng\u01b0\u1eddi d\u00f9ng, thu th\u1eadp ph\u1ea3n h\u1ed3i t\u1eeb c\u00e1c b\u00ean li\u00ean quan ho\u1eb7c ph\u00e2n t\u00edch quy tr\u00ecnh hi\u1ec7n t\u1ea1i \u0111\u1ec3 hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 nhu c\u1ea7u c\u1ee7a d\u1ef1 \u00e1n. Vi\u1ec7c n\u00e0y s\u1ebd gi\u00fap \u0111\u1ea3m b\u1ea3o r\u1eb1ng l\u01b0\u1ee3c \u0111\u1ed3 cu\u1ed1i c\u00f9ng s\u1ebd \u0111\u00e1p \u1ee9ng \u0111\u1ea7y \u0111\u1ee7 c\u00e1c y\u00eau c\u1ea7u th\u1ef1c t\u1ebf.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Thi\u1ebft k\u1ebf s\u01a1 \u0111\u1ed3 l\u01b0\u1ee3c \u0111\u1ed3<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Sau khi \u0111\u00e3 x\u00e1c \u0111\u1ecbnh y\u00eau c\u1ea7u, b\u01b0\u1edbc ti\u1ebfp theo l\u00e0 thi\u1ebft k\u1ebf s\u01a1 \u0111\u1ed3 l\u01b0\u1ee3c \u0111\u1ed3. B\u1ea1n c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng c\u00e1c c\u00f4ng c\u1ee5 tr\u1ef1c quan h\u00f3a nh\u01b0 ERD (Entity-Relationship Diagram) \u0111\u1ec3 m\u00f4 t\u1ea3 c\u00e1c b\u1ea3ng, thu\u1ed9c t\u00ednh v\u00e0 m\u1ed1i quan h\u1ec7 gi\u1eefa ch\u00fang.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Trong giai \u0111o\u1ea1n n\u00e0y, b\u1ea1n c\u0169ng n\u00ean xem x\u00e9t vi\u1ec7c \u00e1p d\u1ee5ng c\u00e1c ti\u00eau chu\u1ea9n v\u00e0 quy t\u1eafc thi\u1ebft k\u1ebf t\u1ed1t nh\u1ea5t nh\u01b0 ph\u00e2n chia d\u1eef li\u1ec7u th\u00e0nh c\u00e1c b\u1ea3ng nh\u1ecf h\u01a1n v\u00e0 s\u1eed d\u1ee5ng c\u00e1c r\u00e0ng bu\u1ed9c \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Tri\u1ec3n khai l\u01b0\u1ee3c \u0111\u1ed3 v\u00e0o h\u1ec7 th\u1ed1ng<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Cu\u1ed1i c\u00f9ng, sau khi ho\u00e0n t\u1ea5t thi\u1ebft k\u1ebf, b\u1ea1n s\u1ebd tri\u1ec3n khai l\u01b0\u1ee3c \u0111\u1ed3 v\u00e0o h\u1ec7 th\u1ed1ng c\u01a1 s\u1edf d\u1eef li\u1ec7u th\u1ef1c t\u1ebf. \u0110i\u1ec1u n\u00e0y c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n b\u1eb1ng c\u00e1ch vi\u1ebft c\u00e1c c\u00e2u l\u1ec7nh SQL \u0111\u1ec3 t\u1ea1o ra c\u00e1c b\u1ea3ng v\u00e0 thi\u1ebft l\u1eadp m\u1ed1i quan h\u1ec7 gi\u1eefa ch\u00fang.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Trong qu\u00e1 tr\u00ecnh n\u00e0y, b\u1ea1n c\u0169ng c\u1ea7n ki\u1ec3m tra v\u00e0 t\u1ed1i \u01b0u h\u00f3a l\u01b0\u1ee3c \u0111\u1ed3 \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng n\u00f3 ho\u1ea1t \u0111\u1ed9ng hi\u1ec7u qu\u1ea3 v\u00e0 \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c nhu c\u1ea7u c\u1ee7a ng\u01b0\u1eddi d\u00f9ng cu\u1ed1i. Vi\u1ec7c n\u00e0y c\u00f3 th\u1ec3 bao g\u1ed3m vi\u1ec7c s\u1eed d\u1ee5ng ch\u1ec9 m\u1ee5c, t\u1ed1i \u01b0u h\u00f3a truy v\u1ea5n v\u00e0 \u0111i\u1ec1u ch\u1ec9nh c\u1ea5u h\u00ecnh h\u1ec7 th\u1ed1ng.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>C\u00e1c thi\u1ebft k\u1ebf database schema<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Thi\u1ebft k\u1ebf l\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u l\u00e0 m\u1ed9t b\u01b0\u1edbc quan tr\u1ecdng quy\u1ebft \u0111\u1ecbnh \u0111\u1ebfn hi\u1ec7u su\u1ea5t v\u00e0 kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng c\u1ee7a h\u1ec7 th\u1ed1ng. C\u00f3 nhi\u1ec1u phong c\u00e1ch thi\u1ebft k\u1ebf kh\u00e1c nhau m\u00e0 b\u1ea1n c\u00f3 th\u1ec3 xem x\u00e9t.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Thi\u1ebft k\u1ebf theo m\u00f4 h\u00ecnh quan h\u1ec7<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">M\u00f4 h\u00ecnh quan h\u1ec7 l\u00e0 m\u1ed9t trong nh\u1eefng ph\u01b0\u01a1ng ph\u00e1p ph\u1ed5 bi\u1ebfn nh\u1ea5t trong thi\u1ebft k\u1ebf c\u01a1 s\u1edf d\u1eef li\u1ec7u. N\u00f3 d\u1ef1a tr\u00ean c\u00e1c b\u1ea3ng v\u00e0 m\u1ed1i quan h\u1ec7 gi\u1eefa ch\u00fang \u0111\u1ec3 t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u. Trong m\u00f4 h\u00ecnh n\u00e0y, m\u1ed7i b\u1ea3ng \u0111\u1ea1i di\u1ec7n cho m\u1ed9t th\u1ef1c th\u1ec3 v\u00e0 m\u1ed7i c\u1ed9t trong b\u1ea3ng \u0111\u1ea1i di\u1ec7n cho m\u1ed9t thu\u1ed9c t\u00ednh c\u1ee7a th\u1ef1c th\u1ec3 \u0111\u00f3.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Vi\u1ec7c s\u1eed d\u1ee5ng m\u00f4 h\u00ecnh quan h\u1ec7 gi\u00fap cho vi\u1ec7c truy v\u1ea5n v\u00e0 qu\u1ea3n l\u00fd d\u1eef li\u1ec7u tr\u1edf n\u00ean d\u1ec5 d\u00e0ng h\u01a1n, v\u00ec ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng c\u00e1c c\u00e2u l\u1ec7nh SQL \u0111\u1ec3 truy xu\u1ea5t th\u00f4ng tin m\u00e0 kh\u00f4ng c\u1ea7n ph\u1ea3i lo l\u1eafng v\u1ec1 c\u00e1ch th\u1ee9c l\u01b0u tr\u1eef d\u1eef li\u1ec7u.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Thi\u1ebft k\u1ebf theo m\u00f4 h\u00ecnh phi quan h\u1ec7<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">M\u00f4 h\u00ecnh phi quan h\u1ec7 (NoSQL) l\u00e0 m\u1ed9t l\u1ef1a ch\u1ecdn kh\u00e1c d\u00e0nh cho nh\u1eefng h\u1ec7 th\u1ed1ng y\u00eau c\u1ea7u kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng cao v\u00e0 t\u00ednh linh ho\u1ea1t trong vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u. Thay v\u00ec t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u th\u00e0nh c\u00e1c b\u1ea3ng, m\u00f4 h\u00ecnh n\u00e0y cho ph\u00e9p l\u01b0u tr\u1eef d\u1eef li\u1ec7u d\u01b0\u1edbi nhi\u1ec1u d\u1ea1ng kh\u00e1c nhau nh\u01b0 t\u00e0i li\u1ec7u, c\u1eb7p kh\u00f3a-gi\u00e1 tr\u1ecb ho\u1eb7c \u0111\u1ed3 th\u1ecb.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Thi\u1ebft k\u1ebf theo m\u00f4 h\u00ecnh phi quan h\u1ec7 th\u01b0\u1eddng \u0111\u01b0\u1ee3c \u01b0a chu\u1ed9ng trong c\u00e1c \u1ee9ng d\u1ee5ng web l\u1edbn, n\u01a1i m\u00e0 t\u1ed1c \u0111\u1ed9 v\u00e0 kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng l\u00e0 y\u1ebfu t\u1ed1 quan tr\u1ecdng. Tuy nhi\u00ean, vi\u1ec7c l\u1ef1a ch\u1ecdn m\u00f4 h\u00ecnh phi quan h\u1ec7 c\u0169ng \u0111i k\u00e8m v\u1edbi nh\u1eefng th\u00e1ch th\u1ee9c v\u00e0 y\u00eau c\u1ea7u chuy\u00ean m\u00f4n cao h\u01a1n trong vi\u1ec7c qu\u1ea3n l\u00fd d\u1eef li\u1ec7u.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Thi\u1ebft k\u1ebf theo m\u00f4 h\u00ecnh \u0111a chi\u1ec1u<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">M\u00f4 h\u00ecnh \u0111a chi\u1ec1u th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong c\u00e1c h\u1ec7 th\u1ed1ng kho d\u1eef li\u1ec7u v\u00e0 ph\u00e2n t\u00edch d\u1eef li\u1ec7u. N\u00f3 cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng truy v\u1ea5n d\u1eef li\u1ec7u t\u1eeb nhi\u1ec1u g\u00f3c \u0111\u1ed9 kh\u00e1c nhau, nh\u1edd v\u00e0o vi\u1ec7c t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u th\u00e0nh c\u00e1c kh\u1ed1i (cubes) v\u00e0 chi\u1ec1u (dimensions).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Thi\u1ebft k\u1ebf theo m\u00f4 h\u00ecnh \u0111a chi\u1ec1u h\u1ed7 tr\u1ee3 vi\u1ec7c ph\u00e2n t\u00edch v\u00e0 b\u00e1o c\u00e1o d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch tr\u1ef1c quan h\u01a1n, gi\u00fap ng\u01b0\u1eddi d\u00f9ng d\u1ec5 d\u00e0ng nh\u1eadn th\u1ea5y c\u00e1c xu h\u01b0\u1edbng v\u00e0 m\u1eabu trong d\u1eef li\u1ec7u. Tuy nhi\u00ean, vi\u1ec7c thi\u1ebft k\u1ebf m\u1ed9t m\u00f4 h\u00ecnh \u0111a chi\u1ec1u hi\u1ec7u qu\u1ea3 \u0111\u00f2i h\u1ecfi ng\u01b0\u1eddi ph\u00e1t tri\u1ec3n c\u1ea7n c\u00f3 ki\u1ebfn th\u1ee9c s\u00e2u r\u1ed9ng v\u1ec1 nhu c\u1ea7u ph\u00e2n t\u00edch d\u1eef li\u1ec7u c\u1ee7a t\u1ed5 ch\u1ee9c.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Nh\u1eefng \u0111i\u1ec1u c\u1ea7n l\u01b0u \u00fd khi thi\u1ebft k\u1ebf database schema<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Thi\u1ebft k\u1ebf m\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u kh\u00f4ng ch\u1ec9 \u0111\u01a1n gi\u1ea3n l\u00e0 t\u1ea1o ra c\u00e1c b\u1ea3ng v\u00e0 m\u1ed1i quan h\u1ec7. C\u00f3 nhi\u1ec1u y\u1ebfu t\u1ed1 c\u1ea7n xem x\u00e9t \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng l\u01b0\u1ee3c \u0111\u1ed3 ho\u1ea1t \u0111\u1ed9ng hi\u1ec7u qu\u1ea3 v\u00e0 \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c nhu c\u1ea7u c\u1ee7a ng\u01b0\u1eddi d\u00f9ng.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>T\u00ednh m\u1edf r\u1ed9ng<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Khi thi\u1ebft k\u1ebf l\u01b0\u1ee3c \u0111\u1ed3, b\u1ea1n c\u1ea7n xem x\u00e9t kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng c\u1ee7a h\u1ec7 th\u1ed1ng. M\u1ed9t c\u01a1 s\u1edf d\u1eef li\u1ec7u t\u1ed1t kh\u00f4ng ch\u1ec9 \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c nhu c\u1ea7u hi\u1ec7n t\u1ea1i m\u00e0 c\u00f2n ph\u1ea3i c\u00f3 kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng \u0111\u1ec3 h\u1ed7 tr\u1ee3 c\u00e1c y\u00eau c\u1ea7u trong t\u01b0\u01a1ng lai.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u1ea1n c\u00f3 th\u1ec3 d\u1ef1 \u0111o\u00e1n m\u1ed9t s\u1ed1 thay \u0111\u1ed5i c\u00f3 th\u1ec3 x\u1ea3y ra trong t\u01b0\u01a1ng lai nh\u01b0 t\u0103ng tr\u01b0\u1edfng l\u01b0\u1ee3ng d\u1eef li\u1ec7u, thay \u0111\u1ed5i trong c\u00e1ch th\u1ee9c truy c\u1eadp d\u1eef li\u1ec7u ho\u1eb7c y\u00eau c\u1ea7u th\u00eam c\u00e1c t\u00ednh n\u0103ng m\u1edbi. Thi\u1ebft k\u1ebf m\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 linh ho\u1ea1t s\u1ebd gi\u00fap b\u1ea1n d\u1ec5 d\u00e0ng th\u1ef1c hi\u1ec7n c\u00e1c thay \u0111\u1ed5i m\u00e0 kh\u00f4ng l\u00e0m gi\u00e1n \u0111o\u1ea1n ho\u1ea1t \u0111\u1ed9ng c\u1ee7a h\u1ec7 th\u1ed1ng.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>T\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Nh\u01b0 \u0111\u00e3 \u0111\u1ec1 c\u1eadp tr\u01b0\u1edbc \u0111\u00f3, t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u l\u00e0 m\u1ed9t y\u1ebfu t\u1ed1 c\u1ef1c k\u1ef3 quan tr\u1ecdng trong thi\u1ebft k\u1ebf c\u01a1 s\u1edf d\u1eef li\u1ec7u. B\u1ea1n c\u1ea7n \u0111\u1ea3m b\u1ea3o r\u1eb1ng d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c nh\u1eadp v\u00e0o h\u1ec7 th\u1ed1ng l\u00e0 ch\u00ednh x\u00e1c v\u00e0 kh\u00f4ng b\u1ecb tr\u00f9ng l\u1eb7p.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1eed d\u1ee5ng c\u00e1c r\u00e0ng bu\u1ed9c nh\u01b0 kh\u00f3a ch\u00ednh, kh\u00f3a ngo\u1ea1i v\u00e0 ki\u1ec3m tra gi\u00e1 tr\u1ecb s\u1ebd gi\u00fap b\u1ea1n gi\u1eef cho d\u1eef li\u1ec7u lu\u00f4n \u1edf tr\u1ea1ng th\u00e1i t\u1ed1t nh\u1ea5t. \u0110\u00e2y c\u0169ng l\u00e0 c\u00e1ch hi\u1ec7u qu\u1ea3 \u0111\u1ec3 ng\u0103n ch\u1eb7n s\u1ef1 xu\u1ea5t hi\u1ec7n c\u1ee7a c\u00e1c l\u1ed7i d\u1eef li\u1ec7u c\u00f3 th\u1ec3 g\u00e2y ra h\u1eadu qu\u1ea3 nghi\u00eam tr\u1ecdng cho doanh nghi\u1ec7p.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Hi\u1ec7u su\u1ea5t truy v\u1ea5n<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Cu\u1ed1i c\u00f9ng, b\u1ea1n c\u1ea7n xem x\u00e9t hi\u1ec7u su\u1ea5t truy v\u1ea5n khi thi\u1ebft k\u1ebf l\u01b0\u1ee3c \u0111\u1ed3. Vi\u1ec7c t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3 s\u1ebd gi\u00fap t\u0103ng t\u1ed1c \u0111\u1ed9 truy xu\u1ea5t v\u00e0 x\u1eed l\u00fd th\u00f4ng tin.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1eed d\u1ee5ng c\u00e1c ch\u1ec9 m\u1ee5c v\u00e0 t\u1ed1i \u01b0u h\u00f3a c\u00e1c c\u00e2u l\u1ec7nh SQL s\u1ebd gi\u00fap c\u1ea3i thi\u1ec7n hi\u1ec7u su\u1ea5t c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u. H\u00e3y nh\u1edb r\u1eb1ng, m\u1ed9t c\u01a1 s\u1edf d\u1eef li\u1ec7u c\u00f3 hi\u1ec7u su\u1ea5t t\u1ed1t s\u1ebd mang l\u1ea1i tr\u1ea3i nghi\u1ec7m ng\u01b0\u1eddi d\u00f9ng t\u1ed1t h\u01a1n v\u00e0 gi\u00fap doanh nghi\u1ec7p \u0111\u1ea1t \u0111\u01b0\u1ee3c c\u00e1c m\u1ee5c ti\u00eau kinh doanh nhanh ch\u00f3ng h\u01a1n.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 Database schema<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Trong qu\u00e1 tr\u00ecnh t\u00ecm hi\u1ec3u v\u1ec1 <strong>database schema<\/strong>, c\u00f3 nhi\u1ec1u c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p m\u00e0 ng\u01b0\u1eddi d\u00f9ng th\u01b0\u1eddng b\u0103n kho\u0103n. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 c\u00e2u h\u1ecfi ti\u00eau bi\u1ec3u c\u00f9ng v\u1edbi c\u00e2u tr\u1ea3 l\u1eddi.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Database schema kh\u00e1c g\u00ec so v\u1edbi database design?<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Database schema<\/strong> l\u00e0 m\u00f4 t\u1ea3 c\u1ea5u tr\u00fac c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u, trong khi <strong>database design<\/strong> l\u00e0 qu\u00e1 tr\u00ecnh t\u1ea1o ra l\u01b0\u1ee3c \u0111\u1ed3 n\u00e0y. N\u00f3i c\u00e1ch kh\u00e1c, schema l\u00e0 k\u1ebft qu\u1ea3 cu\u1ed1i c\u00f9ng c\u1ee7a quy tr\u00ecnh thi\u1ebft k\u1ebf. Trong khi thi\u1ebft k\u1ebf, b\u1ea1n c\u1ea7n x\u00e1c \u0111\u1ecbnh c\u00e1c y\u1ebfu t\u1ed1 nh\u01b0 b\u1ea3ng, m\u1ed1i quan h\u1ec7 v\u00e0 ki\u1ec3u d\u1eef li\u1ec7u tr\u01b0\u1edbc khi th\u1ec3 hi\u1ec7n ch\u00fang d\u01b0\u1edbi d\u1ea1ng m\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>C\u00f3 th\u1ec3 thay \u0111\u1ed5i database schema sau khi \u0111\u00e3 tri\u1ec3n khai kh\u00f4ng?<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00f3 th\u1ec3 thay \u0111\u1ed5i <strong>schema trong database<\/strong>, nh\u01b0ng \u0111i\u1ec1u n\u00e0y c\u1ea7n ph\u1ea3i \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n c\u1ea9n th\u1eadn \u0111\u1ec3 tr\u00e1nh \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn d\u1eef li\u1ec7u hi\u1ec7n t\u1ea1i. N\u1ebfu b\u1ea1n c\u1ea7n thay \u0111\u1ed5i c\u1ea5u tr\u00fac c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u, b\u1ea1n n\u00ean th\u1ef1c hi\u1ec7n sao l\u01b0u d\u1eef li\u1ec7u tr\u01b0\u1edbc v\u00e0 th\u1eed nghi\u1ec7m tr\u00ean m\u00f4i tr\u01b0\u1eddng ph\u00e1t tri\u1ec3n tr\u01b0\u1edbc khi \u00e1p d\u1ee5ng v\u00e0o m\u00f4i tr\u01b0\u1eddng s\u1ea3n xu\u1ea5t.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>L\u1ee3i \u00edch c\u1ee7a vi\u1ec7c s\u1eed d\u1ee5ng schema trong c\u01a1 s\u1edf d\u1eef li\u1ec7u l\u00e0 g\u00ec?<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Vi\u1ec7c s\u1eed d\u1ee5ng <strong>schema sql<\/strong> gi\u00fap t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch h\u1ec7 th\u1ed1ng, t\u0103ng c\u01b0\u1eddng hi\u1ec7u su\u1ea5t truy v\u1ea5n, v\u00e0 b\u1ea3o v\u1ec7 t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u. \u0110i\u1ec1u n\u00e0y r\u1ea5t quan tr\u1ecdng cho b\u1ea5t k\u1ef3 \u1ee9ng d\u1ee5ng n\u00e0o c\u1ea7n qu\u1ea3n l\u00fd d\u1eef li\u1ec7u l\u1edbn v\u00e0 ph\u1ee9c t\u1ea1p.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>T\u1ed5ng k\u1ebft Database schema<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">T\u1ed5ng k\u1ebft l\u1ea1i, database schema l\u00e0 g\u00ec? l\u00e0 m\u1ed9t c\u00e2u h\u1ecfi kh\u00f4ng th\u1ec3 thi\u1ebfu trong l\u0129nh v\u1ef1c qu\u1ea3n l\u00fd d\u1eef li\u1ec7u. L\u01b0\u1ee3c \u0111\u1ed3 n\u00e0y kh\u00f4ng ch\u1ec9 gi\u00fap t\u1ed5 ch\u1ee9c d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch h\u1ee3p l\u00fd m\u00e0 c\u00f2n n\u00e2ng cao hi\u1ec7u su\u1ea5t v\u00e0 b\u1ea3o v\u1ec7 t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a th\u00f4ng tin. B\u1eb1ng c\u00e1ch hi\u1ec3u r\u00f5 v\u1ec1 c\u00e1c lo\u1ea1i l\u01b0\u1ee3c \u0111\u1ed3, l\u1ee3i \u00edch c\u1ee7a ch\u00fang v\u00e0 c\u00e1ch thi\u1ebft k\u1ebf hi\u1ec7u qu\u1ea3, b\u1ea1n s\u1ebd c\u00f3 th\u1ec3 x\u00e2y d\u1ef1ng m\u1ed9t h\u1ec7 th\u1ed1ng c\u01a1 s\u1edf d\u1eef li\u1ec7u ch\u1ea5t l\u01b0\u1ee3ng v\u00e0 \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c m\u1ecdi y\u00eau c\u1ea7u c\u1ee7a ng\u01b0\u1eddi d\u00f9ng.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00f9ng v\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n kh\u00f4ng ng\u1eebng c\u1ee7a c\u00f4ng ngh\u1ec7, vi\u1ec7c n\u1eafm b\u1eaft v\u00e0 \u1ee9ng d\u1ee5ng c\u00e1c kh\u00e1i ni\u1ec7m nh\u01b0 <strong>schema trong SQL<\/strong> s\u1ebd gi\u00fap b\u1ea1n kh\u00f4ng ch\u1ec9 \u0111\u1ee9ng v\u1eefng trong l\u0129nh v\u1ef1c n\u00e0y m\u00e0 c\u00f2n m\u1edf ra nhi\u1ec1u c\u01a1 h\u1ed9i m\u1edbi cho s\u1ef1 nghi\u1ec7p c\u1ee7a m\u00ecnh.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>K\u1ebft lu\u1eadn<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Trong th\u1ebf gi\u1edbi ng\u00e0y nay, n\u01a1i m\u00e0 th\u00f4ng tin v\u00e0 d\u1eef li\u1ec7u tr\u1edf th\u00e0nh t\u00e0i s\u1ea3n qu\u00fd gi\u00e1, vi\u1ec7c hi\u1ec3u v\u00e0 \u00e1p d\u1ee5ng c\u00e1c nguy\u00ean t\u1eafc c\u1ee7a database schema l\u00e0 \u0111i\u1ec1u v\u00f4 c\u00f9ng c\u1ea7n thi\u1ebft. Kh\u00f4ng ch\u1ec9 gi\u00fap b\u1ea1n t\u1ed1i \u01b0u h\u00f3a vi\u1ec7c qu\u1ea3n l\u00fd d\u1eef li\u1ec7u m\u00e0 c\u00f2n n\u00e2ng cao hi\u1ec7u su\u1ea5t v\u00e0 \u0111\u1ed9 tin c\u1eady c\u1ee7a h\u1ec7 th\u1ed1ng. Hy v\u1ecdng qua b\u00e0i vi\u1ebft n\u00e0y, b\u1ea1n \u0111\u00e3 c\u00f3 c\u00e1i nh\u00ecn s\u00e2u s\u1eafc h\u01a1n v\u1ec1 database schema l\u00e0 g\u00ec? v\u00e0 c\u00f3 th\u1ec3 \u00e1p d\u1ee5ng nh\u1eefng ki\u1ebfn th\u1ee9c n\u00e0y v\u00e0o th\u1ef1c ti\u1ec5n.<\/p>\n\n\n\n<p class=\"has-text-align-right wp-block-paragraph\"><strong>Tr\u00ed Nh\u00e2n. <\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Database schema l\u00e0 g\u00ec? \u0110\u00e2y l\u00e0 m\u1ed9t c\u00e2u h\u1ecfi quan tr\u1ecdng trong l\u0129nh v\u1ef1c qu\u1ea3n l\u00fd d\u1eef li\u1ec7u v\u00e0 h\u1ec7 th\u1ed1ng th\u00f4ng tin. Khi b\u1ea1n &#8230;<\/p>\n","protected":false},"author":58,"featured_media":9111,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17],"tags":[],"class_list":["post-9088","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tu-van-nghe-nghiep"],"_links":{"self":[{"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/posts\/9088","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/users\/58"}],"replies":[{"embeddable":true,"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/comments?post=9088"}],"version-history":[{"count":3,"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/posts\/9088\/revisions"}],"predecessor-version":[{"id":27464,"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/posts\/9088\/revisions\/27464"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/media\/9111"}],"wp:attachment":[{"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/media?parent=9088"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/categories?post=9088"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.careerlink.vn\/cam-nang-viec-lam\/wp-json\/wp\/v2\/tags?post=9088"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}