{"id":1647,"date":"2026-04-06T16:52:31","date_gmt":"2026-04-06T16:52:31","guid":{"rendered":"https:\/\/www.viz-note.com\/vi\/refactoring-overgrown-erd-without-data-loss\/"},"modified":"2026-04-06T16:52:31","modified_gmt":"2026-04-06T16:52:31","slug":"refactoring-overgrown-erd-without-data-loss","status":"publish","type":"post","link":"https:\/\/www.viz-note.com\/vi\/refactoring-overgrown-erd-without-data-loss\/","title":{"rendered":"H\u01b0\u1edbng d\u1eabn nhanh \u0111\u1ec3 t\u00e1i c\u1ea5u tr\u00fac c\u00e1c s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 qu\u00e1 l\u1edbn m\u00e0 kh\u00f4ng m\u1ea5t d\u1eef li\u1ec7u"},"content":{"rendered":"<p>C\u00e1c l\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u l\u00e0 nh\u1eefng t\u00e1c ph\u1ea9m s\u1ed1ng \u0111\u1ed9ng. Ch\u00fang ph\u00e1t tri\u1ec3n song song v\u1edbi logic kinh doanh m\u00e0 ch\u00fang h\u1ed7 tr\u1ee3. Theo th\u1eddi gian, khi y\u00eau c\u1ea7u thay \u0111\u1ed5i v\u00e0 c\u00e1c t\u00ednh n\u0103ng m\u1edbi \u0111\u01b0\u1ee3c gi\u1edbi thi\u1ec7u, c\u1ea5u tr\u00fac d\u1eef li\u1ec7u n\u1ec1n t\u1ea3ng th\u01b0\u1eddng tr\u1edf n\u00ean ph\u1ee9c t\u1ea1p. S\u1ef1 ph\u1ee9c t\u1ea1p n\u00e0y th\u1ec3 hi\u1ec7n tr\u1ef1c quan d\u01b0\u1edbi d\u1ea1ng s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 (ERD) qu\u00e1 l\u1edbn. M\u1ed9t s\u01a1 \u0111\u1ed3 ERD b\u1ecb ph\u00ecnh to c\u00f3 th\u1ec3 d\u1eabn \u0111\u1ebfn suy gi\u1ea3m hi\u1ec7u su\u1ea5t, nh\u1eefng c\u01a1n \u00e1c m\u1ed9ng trong b\u1ea3o tr\u00ec v\u00e0 nguy c\u01a1 cao h\u01a1n v\u1ec1 c\u00e1c v\u1ea5n \u0111\u1ec1 to\u00e0n v\u1eb9n d\u1eef li\u1ec7u.<\/p>\n<p>Vi\u1ec7c t\u00e1i c\u1ea5u tr\u00fac c\u00e1c s\u01a1 \u0111\u1ed3 n\u00e0y kh\u00f4ng ch\u1ec9 \u0111\u01a1n thu\u1ea7n l\u00e0 m\u1ed9t thao t\u00e1c th\u1ea9m m\u1ef9. \u0110\u00f3 l\u00e0 m\u1ed9t can thi\u1ec7p c\u1ea5u tr\u00fac \u0111\u00f2i h\u1ecfi s\u1ef1 ch\u00ednh x\u00e1c. M\u1ee5c ti\u00eau ch\u00ednh l\u00e0 l\u00e0m cho l\u01b0\u1ee3c \u0111\u1ed3 tr\u1edf n\u00ean g\u1ecdn g\u00e0ng h\u01a1n, c\u1ea3i thi\u1ec7n kh\u1ea3 n\u0103ng \u0111\u1ecdc hi\u1ec3u v\u00e0 t\u1ed1i \u01b0u hi\u1ec7u su\u1ea5t truy v\u1ea5n, \u0111\u1ed3ng th\u1eddi \u0111\u1ea3m b\u1ea3o tuy\u1ec7t \u0111\u1ed1i kh\u00f4ng m\u1ea5t d\u1eef li\u1ec7u hay l\u00e0m h\u1ecfng d\u1eef li\u1ec7u trong qu\u00e1 tr\u00ecnh chuy\u1ec3n \u0111\u1ed5i. H\u01b0\u1edbng d\u1eabn n\u00e0y cung c\u1ea5p m\u1ed9t c\u00e1ch ti\u1ebfp c\u1eadn c\u00f3 c\u1ea5u tr\u00fac \u0111\u1ec3 qu\u1ea3n l\u00fd qu\u00e1 tr\u00ecnh n\u00e0y.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><img alt=\"Whimsical infographic illustrating a step-by-step guide to refactoring overgrown Entity Relationship Diagrams without data loss, featuring a garden metaphor with tangled database vines transforming into an organized schema, highlighting preparation phases, normalization techniques (1NF-3NF), data integrity safeguards, common pitfalls with solutions, and post-refactoring validation checkpoints in a playful hand-drawn style.\" decoding=\"async\" src=\"https:\/\/www.viz-note.com\/wp-content\/uploads\/2026\/04\/whimsical-erd-refactoring-guide-infographic-16x9-1.jpg\"\/><\/figure>\n<\/div>\n<h2>\ud83d\udcc9 T\u1ea1i sao c\u00e1c s\u01a1 \u0111\u1ed3 ERD tr\u1edf n\u00ean kh\u00f4ng th\u1ec3 ki\u1ec3m so\u00e1t \u0111\u01b0\u1ee3c<\/h2>\n<p>Hi\u1ec3u r\u00f5 nguy\u00ean nh\u00e2n g\u1ed1c r\u1ec5 c\u1ee7a s\u1ef1 ph\u00ecnh to l\u01b0\u1ee3c \u0111\u1ed3 l\u00e0 b\u01b0\u1edbc \u0111\u1ea7u ti\u00ean \u0111\u1ec3 gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1. M\u1ed9t s\u01a1 \u0111\u1ed3 ERD ph\u00e1t tri\u1ec3n t\u1ef1 nhi\u00ean m\u00e0 kh\u00f4ng c\u00f3 s\u1ef1 qu\u1ea3n l\u00fd th\u01b0\u1eddng th\u1ec3 hi\u1ec7n nh\u1eefng tri\u1ec7u ch\u1ee9ng c\u1ee5 th\u1ec3. Nh\u1eadn di\u1ec7n \u0111\u01b0\u1ee3c nh\u1eefng m\u1eabu h\u00ecnh n\u00e0y cho ph\u00e9p can thi\u1ec7p m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c.<\/p>\n<ul>\n<li><strong>C\u00e1c c\u1ed9t tr\u00f9ng l\u1eb7p:<\/strong> C\u00f9ng m\u1ed9t \u0111i\u1ec3m d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong nhi\u1ec1u b\u1ea3ng. \u0110i\u1ec1u n\u00e0y t\u1ea1o ra c\u00e1c th\u00e1ch th\u1ee9c \u0111\u1ed3ng b\u1ed9 h\u00f3a, n\u01a1i c\u1eadp nh\u1eadt m\u1ed9t b\u1ea3n sao kh\u00f4ng l\u00e0m c\u1eadp nh\u1eadt b\u1ea3n sao c\u00f2n l\u1ea1i.<\/li>\n<li><strong>S\u1eed d\u1ee5ng qu\u00e1 m\u1ee9c vi\u1ec7c kh\u00f4ng chu\u1ea9n h\u00f3a:<\/strong> Trong khi vi\u1ec7c kh\u00f4ng chu\u1ea9n h\u00f3a c\u1ea3i thi\u1ec7n t\u1ed1c \u0111\u1ed9 \u0111\u1ecdc, vi\u1ec7c s\u1eed d\u1ee5ng qu\u00e1 m\u1ee9c s\u1ebd l\u00e0m ph\u1ee9c t\u1ea1p c\u00e1c thao t\u00e1c ghi v\u00e0 l\u00e0m t\u0103ng chi ph\u00ed l\u01b0u tr\u1eef.<\/li>\n<li><strong>C\u00e1c m\u1ed1i quan h\u1ec7 y\u1ebfu:<\/strong> C\u00e1c m\u1ed1i quan h\u1ec7 nhi\u1ec1u &#8211; nhi\u1ec1u th\u01b0\u1eddng \u0111\u01b0\u1ee3c tri\u1ec3n khai b\u1eb1ng m\u1ed9t b\u1ea3ng duy nh\u1ea5t v\u1edbi nhi\u1ec1u kh\u00f3a ngo\u1ea1i, thay v\u00ec s\u1eed d\u1ee5ng c\u00e1c b\u1ea3ng li\u00ean k\u1ebft \u0111\u00fang chu\u1ea9n.<\/li>\n<li><strong>Logic kinh doanh \u1ea9n:<\/strong> C\u00e1c ki\u1ec3u d\u1eef li\u1ec7u v\u00e0 r\u00e0ng bu\u1ed9c c\u00f3 th\u1ec3 d\u1ef1a v\u00e0o c\u00e1c ki\u1ec3m tra \u1edf c\u1ea5p \u0111\u1ed9 \u1ee9ng d\u1ee5ng thay v\u00ec th\u1ef1c thi \u1edf c\u1ea5p \u0111\u1ed9 c\u01a1 s\u1edf d\u1eef li\u1ec7u, l\u00e0m cho l\u01b0\u1ee3c \u0111\u1ed3 tr\u1edf n\u00ean mong manh.<\/li>\n<li><strong>C\u00e1c th\u1ef1c th\u1ec3 b\u1ecb b\u1ecf r\u01a1i:<\/strong> C\u00f3 nh\u1eefng b\u1ea3ng t\u1ed3n t\u1ea1i m\u00e0 kh\u00f4ng c\u00f2n \u0111\u01b0\u1ee3c tham chi\u1ebfu b\u1edfi b\u1ea5t k\u1ef3 m\u00f4-\u0111un \u1ee9ng d\u1ee5ng n\u00e0o \u0111ang ho\u1ea1t \u0111\u1ed9ng, nh\u01b0ng v\u1eabn c\u00f2n trong b\u1ed9 nh\u1edb v\u1eadt l\u00fd.<\/li>\n<\/ul>\n<p>Khi nh\u1eefng y\u1ebfu t\u1ed1 n\u00e0y t\u00edch t\u1ee5 l\u1ea1i, s\u01a1 \u0111\u1ed3 ERD tr\u1edf th\u00e0nh m\u1ed9t m\u1ea1ng l\u01b0\u1edbi r\u1ed1i ren. Vi\u1ec7c tr\u1ef1c quan h\u00f3a c\u00e1c m\u1ed1i quan h\u1ec7 tr\u1edf n\u00ean kh\u00f3 kh\u0103n, v\u00e0 nguy c\u01a1 g\u00e2y ra l\u1ed7i trong b\u1ea5t k\u1ef3 thay \u0111\u1ed5i n\u00e0o \u0111\u1ec1u t\u0103ng theo c\u1ea5p s\u1ed1 nh\u00e2n.<\/p>\n<h2>\ud83d\udee1\ufe0f Chu\u1ea9n b\u1ecb cho c\u00e1c thay \u0111\u1ed5i l\u01b0\u1ee3c \u0111\u1ed3<\/h2>\n<p>Tr\u01b0\u1edbc khi thao t\u00e1c b\u1ea5t k\u1ef3 d\u00f2ng l\u1ec7nh DDL (Ng\u00f4n ng\u1eef \u0111\u1ecbnh ngh\u0129a d\u1eef li\u1ec7u) n\u00e0o, giai \u0111o\u1ea1n chu\u1ea9n b\u1ecb nghi\u00eam ng\u1eb7t l\u00e0 b\u1eaft bu\u1ed9c. Giai \u0111o\u1ea1n n\u00e0y gi\u00fap gi\u1ea3m thi\u1ec3u r\u1ee7i ro v\u00e0 \u0111\u1ea3m b\u1ea3o c\u00f3 th\u1ec3 ho\u00e0n nguy\u00ean n\u1ebfu x\u1ea3y ra s\u1ef1 c\u1ed1.<\/p>\n<h3>1. Chi\u1ebfn l\u01b0\u1ee3c sao l\u01b0u to\u00e0n di\u1ec7n<\/h3>\n<p>An to\u00e0n d\u1eef li\u1ec7u l\u00e0 \u01b0u ti\u00ean h\u00e0ng \u0111\u1ea7u. M\u1ed9t b\u1ea3n sao l\u01b0u kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t t\u1eadp tin; \u0111\u00f3 l\u00e0 \u0111i\u1ec3m x\u00e1c th\u1ef1c.<\/p>\n<ul>\n<li><strong>Sao l\u01b0u logic:<\/strong> Xu\u1ea5t \u0111\u1ecbnh ngh\u0129a l\u01b0\u1ee3c \u0111\u1ed3 v\u00e0 d\u1eef li\u1ec7u d\u01b0\u1edbi d\u1ea1ng \u0111\u1ecbnh d\u1ea1ng d\u1ec5 \u0111\u1ecdc b\u1edfi con ng\u01b0\u1eddi (v\u00ed d\u1ee5: c\u00e1c t\u1eadp tin dump SQL).<\/li>\n<li><strong>C\u00e1c b\u1ea3n ch\u1ee5p v\u1eadt l\u00fd:<\/strong> N\u1ebfu n\u1ec1n t\u1ea3ng h\u1ed7 tr\u1ee3, h\u00e3y t\u1ea1o m\u1ed9t b\u1ea3n ch\u1ee5p \u0111i\u1ec3m th\u1eddi gian c\u1ee7a kh\u1ed1i l\u01b0u tr\u1eef.<\/li>\n<li><strong>B\u1ea3n sao ch\u1ec9 \u0111\u1ecdc:<\/strong> N\u1ebfu c\u00f3 th\u1ec3, kh\u1edfi ch\u1ea1y m\u1ed9t b\u1ea3n sao c\u1ee7a m\u00f4i tr\u01b0\u1eddng s\u1ea3n xu\u1ea5t. Th\u1ef1c hi\u1ec7n t\u1ea5t c\u1ea3 c\u00e1c b\u00e0i ki\u1ec3m th\u1eed v\u00e0 k\u1ecbch b\u1ea3n di chuy\u1ec3n \u1edf \u0111\u00e2y tr\u01b0\u1edbc ti\u00ean.<\/li>\n<\/ul>\n<h3>2. B\u1ea3n \u0111\u1ed3 ph\u1ee5 thu\u1ed9c<\/h3>\n<p>C\u00e1c b\u1ea3ng kh\u00f4ng t\u1ed3n t\u1ea1i m\u1ed9t c\u00e1ch c\u00f4 l\u1eadp. M\u1ed7i th\u1ef1c th\u1ec3 \u0111\u1ec1u \u0111\u01b0\u1ee3c tham chi\u1ebfu b\u1edfi m\u00e3 \u1ee9ng d\u1ee5ng, th\u1ee7 t\u1ee5c l\u01b0u tr\u1eef ho\u1eb7c c\u00e1c c\u00f4ng c\u1ee5 b\u00e1o c\u00e1o b\u00ean ngo\u00e0i. B\u1ea1n ph\u1ea3i x\u00e1c \u0111\u1ecbnh m\u1ecdi ng\u01b0\u1eddi d\u00f9ng d\u1eef li\u1ec7u.<\/p>\n<ul>\n<li>Xem x\u00e9t m\u00e3 \u1ee9ng d\u1ee5ng \u0111\u1ec3 t\u00ecm c\u00e1c tham chi\u1ebfu tr\u1ef1c ti\u1ebfp \u0111\u1ebfn b\u1ea3ng.<\/li>\n<li>Ki\u1ec3m tra c\u00e1c view ho\u1eb7c c\u00e1c view \u0111\u01b0\u1ee3c v\u1eadt ch\u1ea5t h\u00f3a ph\u1ee5 thu\u1ed9c v\u00e0o c\u00e1c c\u1ed9t c\u1ee5 th\u1ec3.<\/li>\n<li>X\u00e1c \u0111\u1ecbnh b\u1ea5t k\u1ef3 c\u00f4ng vi\u1ec7c \u0111\u01b0\u1ee3c l\u00ean l\u1ecbch n\u00e0o ho\u1eb7c quy tr\u00ecnh ETL (tr\u00edch xu\u1ea5t, chuy\u1ec3n \u0111\u1ed5i, t\u1ea3i) n\u00e0o \u0111ang nh\u1eadp ho\u1eb7c xu\u1ea5t d\u1eef li\u1ec7u t\u1eeb c\u00e1c b\u1ea3ng b\u1ecb \u1ea3nh h\u01b0\u1edfng.<\/li>\n<\/ul>\n<h3>3. Ph\u00e2n t\u00edch t\u00e1c \u0111\u1ed9ng<\/h3>\n<p>T\u00e0i li\u1ec7u tr\u1ea1ng th\u00e1i hi\u1ec7n t\u1ea1i. T\u1ea1o c\u01a1 s\u1edf d\u1eef li\u1ec7u v\u1ec1 s\u1ed1 l\u01b0\u1ee3ng h\u00e0ng, ph\u00e2n b\u1ed1 d\u1eef li\u1ec7u v\u00e0 th\u1eddi gian th\u1ef1c thi truy v\u1ea5n. C\u01a1 s\u1edf n\u00e0y cho ph\u00e9p b\u1ea1n so s\u00e1nh tr\u1ea1ng th\u00e1i h\u1ec7 th\u1ed1ng tr\u01b0\u1edbc v\u00e0 sau khi t\u00e1i c\u1ea5u tr\u00fac \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u00ednh nh\u1ea5t qu\u00e1n.<\/p>\n<table>\n<thead>\n<tr>\n<th>M\u1ee5c ki\u1ec3m tra<\/th>\n<th>\u01afu ti\u00ean<\/th>\n<th>Ghi ch\u00fa<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>X\u00e1c minh t\u00ednh \u0111\u1ea7y \u0111\u1ee7 c\u1ee7a b\u1ea3n sao l\u01b0u<\/td>\n<td>Cao<\/td>\n<td>\u0110\u1ea3m b\u1ea3o c\u00e1c t\u1ed5ng ki\u1ec3m tra kh\u1edbp v\u1edbi ngu\u1ed3n<\/td>\n<\/tr>\n<tr>\n<td>B\u1ea3n \u0111\u1ed3 t\u1ea5t c\u1ea3 c\u00e1c kh\u00f3a ngo\u1ea1i<\/td>\n<td>Cao<\/td>\n<td>T\u00e0i li\u1ec7u c\u00e1c m\u1ed1i quan h\u1ec7 cha-con<\/td>\n<\/tr>\n<tr>\n<td>X\u00e1c \u0111\u1ecbnh c\u00e1c truy v\u1ea5n \u0111ang ho\u1ea1t \u0111\u1ed9ng<\/td>\n<td>Trung b\u00ecnh<\/td>\n<td>S\u1eed d\u1ee5ng nh\u1eadt k\u00fd truy v\u1ea5n \u0111\u1ec3 t\u00ecm c\u00e1c truy v\u1ea5n chi\u1ebfm nhi\u1ec1u t\u00e0i nguy\u00ean<\/td>\n<\/tr>\n<tr>\n<td>Xem x\u00e9t c\u00e1c ki\u1ec3m so\u00e1t truy c\u1eadp<\/td>\n<td>Trung b\u00ecnh<\/td>\n<td>\u0110\u1ea3m b\u1ea3o quy\u1ec1n h\u1ea1n \u0111\u01b0\u1ee3c duy tr\u00ec sau khi di chuy\u1ec3n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>\ud83d\udd04 Ph\u01b0\u01a1ng ph\u00e1p t\u00e1i c\u1ea5u tr\u00fac<\/h2>\n<p>H\u1ea1t nh\u00e2n c\u1ee7a vi\u1ec7c t\u00e1i c\u1ea5u tr\u00fac bao g\u1ed3m vi\u1ec7c t\u00e1i c\u1ea5u tr\u00fac m\u00f4 h\u00ecnh logic. \u0110i\u1ec1u n\u00e0y th\u01b0\u1eddng \u0111\u1ea1t \u0111\u01b0\u1ee3c th\u00f4ng qua chu\u1ea9n h\u00f3a, m\u1eb7c d\u00f9 vi\u1ec7c phi chu\u1ea9n h\u00f3a chi\u1ebfn l\u01b0\u1ee3c c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c gi\u1eef l\u1ea1i nh\u1eb1m c\u1ea3i thi\u1ec7n hi\u1ec7u su\u1ea5t. M\u1ee5c ti\u00eau l\u00e0 s\u1ef1 r\u00f5 r\u00e0ng v\u00e0 to\u00e0n v\u1eb9n.<\/p>\n<h3>1. Ph\u00e2n t\u00edch chu\u1ea9n h\u00f3a hi\u1ec7n t\u1ea1i<\/h3>\n<p>H\u1ea7u h\u1ebft c\u00e1c l\u01b0\u1ee3c \u0111\u1ed3 c\u0169 \u0111\u1ec1u ch\u01b0a \u0111\u1ea1t \u0111\u1ebfn d\u1ea1ng chu\u1ea9n h\u00f3a th\u1ee9 ba (3NF). Vi\u1ec7c ti\u1ebfn t\u1edbi chu\u1ea9n h\u00f3a cao h\u01a1n s\u1ebd gi\u1ea3m thi\u1ec3u s\u1ef1 tr\u00f9ng l\u1eb7p.<\/p>\n<ul>\n<li><strong>D\u1ea1ng chu\u1ea9n h\u00f3a th\u1ee9 nh\u1ea5t (1NF):<\/strong>\u0110\u1ea3m b\u1ea3o t\u00ednh nguy\u00ean t\u1eed. Kh\u00f4ng c\u00f3 nh\u00f3m l\u1eb7p l\u1ea1i ho\u1eb7c thu\u1ed9c t\u00ednh \u0111a gi\u00e1 tr\u1ecb trong m\u1ed9t \u00f4 duy nh\u1ea5t.<\/li>\n<li><strong>D\u1ea1ng chu\u1ea9n h\u00f3a th\u1ee9 hai (2NF):<\/strong>Lo\u1ea1i b\u1ecf c\u00e1c ph\u1ee5 thu\u1ed9c ri\u00eang ph\u1ea7n. \u0110\u1ea3m b\u1ea3o m\u1ecdi thu\u1ed9c t\u00ednh kh\u00f4ng kh\u00f3a \u0111\u1ec1u ph\u1ee5 thu\u1ed9c ho\u00e0n to\u00e0n v\u00e0o kh\u00f3a ch\u00ednh.<\/li>\n<li><strong>D\u1ea1ng chu\u1ea9n h\u00f3a th\u1ee9 ba (3NF):<\/strong>Lo\u1ea1i b\u1ecf c\u00e1c ph\u1ee5 thu\u1ed9c b\u1eafc c\u1ea7u. C\u00e1c thu\u1ed9c t\u00ednh kh\u00f4ng kh\u00f3a ch\u1ec9 n\u00ean ph\u1ee5 thu\u1ed9c v\u00e0o kh\u00f3a, ch\u1ee9 kh\u00f4ng ph\u1ee5 thu\u1ed9c v\u00e0o c\u00e1c thu\u1ed9c t\u00ednh kh\u00f4ng kh\u00f3a kh\u00e1c.<\/li>\n<\/ul>\n<table>\n<thead>\n<tr>\n<th>M\u1ee9c \u0111\u1ed9 chu\u1ea9n h\u00f3a<\/th>\n<th>Quy t\u1eafc ch\u00ednh<\/th>\n<th>L\u1ee3i \u00edch<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1NF<\/td>\n<td>Ch\u1ec9 gi\u00e1 tr\u1ecb nguy\u00ean t\u1eed<\/td>\n<td>Lo\u1ea1i b\u1ecf logic ph\u00e2n t\u00edch ph\u1ee9c t\u1ea1p<\/td>\n<\/tr>\n<tr>\n<td>2NF<\/td>\n<td>Ph\u1ee5 thu\u1ed9c \u0111\u1ea7y \u0111\u1ee7 v\u00e0o kh\u00f3a ch\u00ednh<\/td>\n<td>Gi\u1ea3m c\u00e1c b\u1ea5t th\u01b0\u1eddng khi c\u1eadp nh\u1eadt<\/td>\n<\/tr>\n<tr>\n<td>3NF<\/td>\n<td>Kh\u00f4ng c\u00f3 ph\u1ee5 thu\u1ed9c b\u1eafc c\u1ea7u<\/td>\n<td>C\u1ea3i thi\u1ec7n t\u00ednh nh\u1ea5t qu\u00e1n c\u1ee7a d\u1eef li\u1ec7u<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>2. Ph\u00e2n r\u00e3 c\u00e1c th\u1ef1c th\u1ec3 l\u1edbn<\/h3>\n<p>Khi m\u1ed9t b\u1ea3ng duy nh\u1ea5t ch\u1ee9a qu\u00e1 nhi\u1ec1u c\u1ed9t, \u0111i\u1ec1u n\u00e0y th\u01b0\u1eddng ng\u1ee5 \u00fd r\u1eb1ng c\u00e1c kh\u00e1i ni\u1ec7m kinh doanh ri\u00eang bi\u1ec7t \u0111ang b\u1ecb g\u1ed9p l\u1ea1i v\u1edbi nhau. H\u00e3y chia ch\u00fang th\u00e0nh c\u00e1c b\u1ea3ng ri\u00eang bi\u1ec7t.<\/p>\n<ul>\n<li>X\u00e1c \u0111\u1ecbnh c\u00e1c nh\u00f3m c\u1ed9t m\u00f4 t\u1ea3 c\u00e1c th\u1ef1c th\u1ec3 kh\u00e1c nhau (v\u00ed d\u1ee5: H\u1ed3 s\u01a1 ng\u01b0\u1eddi d\u00f9ng so v\u1edbi C\u00e0i \u0111\u1eb7t ng\u01b0\u1eddi d\u00f9ng).<\/li>\n<li>T\u1ea1o m\u1ed9t b\u1ea3ng m\u1edbi cho kh\u00e1i ni\u1ec7m ri\u00eang bi\u1ec7t.<\/li>\n<li>Chuy\u1ec3n c\u00e1c c\u1ed9t li\u00ean quan sang b\u1ea3ng m\u1edbi.<\/li>\n<li>Thi\u1ebft l\u1eadp m\u1ed1i quan h\u1ec7 m\u1ed9t-m\u1ed9t b\u1eb1ng c\u00e1ch s\u1eed d\u1ee5ng kh\u00f3a ngo\u1ea1i.<\/li>\n<\/ul>\n<h3>3. Gi\u1ea3i quy\u1ebft c\u00e1c m\u1ed1i quan h\u1ec7 nhi\u1ec1u-nhi\u1ec1u<\/h3>\n<p>Li\u00ean k\u1ebft tr\u1ef1c ti\u1ebfp hai b\u1ea3ng b\u1eb1ng m\u1ed9t c\u1ed9t \u1edf m\u1ed7i b\u1ea3ng l\u00e0 m\u1ed9t m\u1eabu sai ph\u1ed5 bi\u1ebfn. \u0110i\u1ec1u n\u00e0y n\u00ean \u0111\u01b0\u1ee3c thay th\u1ebf b\u1eb1ng m\u1ed9t b\u1ea3ng c\u1ea7u n\u1ed1i.<\/p>\n<ul>\n<li>T\u1ea1o m\u1ed9t b\u1ea3ng m\u1edbi \u0111\u1ec3 l\u00e0m c\u1ea7u n\u1ed1i.<\/li>\n<li>Bao g\u1ed3m c\u00e1c kh\u00f3a ch\u00ednh t\u1eeb c\u1ea3 hai b\u1ea3ng cha nh\u01b0 kh\u00f3a ngo\u1ea1i trong b\u1ea3ng c\u1ea7u n\u1ed1i.<\/li>\n<li>Th\u00eam b\u1ea5t k\u1ef3 thu\u1ed9c t\u00ednh c\u1ee5 th\u1ec3 n\u00e0o thu\u1ed9c v\u1ec1 ch\u00ednh m\u1ed1i quan h\u1ec7 \u0111\u00f3 (v\u00ed d\u1ee5: ng\u00e0y m\u1ed1i quan h\u1ec7 \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp).<\/li>\n<\/ul>\n<h3>4. X\u1eed l\u00fd d\u1eef li\u1ec7u l\u1ecbch s\u1eed<\/h3>\n<p>Vi\u1ec7c t\u00e1i c\u1ea5u tr\u00fac th\u01b0\u1eddng thay \u0111\u1ed5i c\u00e1ch d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef. C\u00e1c b\u1ea3n ghi l\u1ecbch s\u1eed ph\u1ea3i \u0111\u01b0\u1ee3c b\u1ea3o t\u1ed3n ch\u00ednh x\u00e1c.<\/p>\n<ul>\n<li>Kh\u00f4ng \u0111\u01a1n gi\u1ea3n x\u00f3a d\u1eef li\u1ec7u c\u0169. D\u1eef li\u1ec7u n\u00e0y c\u00f3 th\u1ec3 c\u1ea7n thi\u1ebft cho c\u00e1c b\u1ea3n ghi ki\u1ec3m to\u00e1n ho\u1eb7c tu\u00e2n th\u1ee7 ph\u00e1p l\u00fd.<\/li>\n<li>S\u1eed d\u1ee5ng c\u00e1c t\u1eadp l\u1ec7nh di chuy\u1ec3n \u0111\u1ec3 chuy\u1ec3n \u0111\u1ed5i d\u1eef li\u1ec7u hi\u1ec7n c\u00f3 sang \u0111\u1ecbnh d\u1ea1ng m\u1edbi tr\u01b0\u1edbc khi chuy\u1ec3n k\u1ebft n\u1ed1i \u1ee9ng d\u1ee5ng.<\/li>\n<li>L\u01b0u tr\u1eef c\u00e1c b\u1ea3ng c\u0169 n\u1ebfu ch\u00fang kh\u00f4ng c\u00f2n c\u1ea7n thi\u1ebft nh\u01b0ng ph\u1ea3i \u0111\u01b0\u1ee3c gi\u1eef l\u1ea1i v\u00ec m\u1ee5c \u0111\u00edch l\u01b0u tr\u1eef h\u1ed3 s\u01a1.<\/li>\n<\/ul>\n<h2>\u2705 \u0110\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u<\/h2>\n<p>Trong qu\u00e1 tr\u00ecnh chuy\u1ec3n \u0111\u1ed5i, r\u1ee7i ro d\u1eef li\u1ec7u b\u1ecb h\u1ecfng l\u00e0 cao nh\u1ea5t. C\u00e1c r\u00e0ng bu\u1ed9c to\u00e0n v\u1eb9n l\u00e0 m\u1ea1ng an to\u00e0n c\u1ee7a b\u1ea1n.<\/p>\n<h3>1. R\u00e0ng bu\u1ed9c kh\u00f3a ngo\u1ea1i<\/h3>\n<p>Th\u1ef1c thi t\u00ednh to\u00e0n v\u1eb9n tham chi\u1ebfu \u1edf c\u1ea5p \u0111\u1ed9 c\u01a1 s\u1edf d\u1eef li\u1ec7u. \u0110i\u1ec1u n\u00e0y ng\u0103n ch\u1eb7n c\u00e1c b\u1ea3n ghi m\u1ed3 c\u00f4i, n\u01a1i b\u1ea3n ghi con tham chi\u1ebfu \u0111\u1ebfn b\u1ea3n ghi cha kh\u00f4ng c\u00f2n t\u1ed3n t\u1ea1i.<\/p>\n<ul>\n<li>K\u00edch ho\u1ea1t <code>CASCADE<\/code>c\u1eadp nh\u1eadt ho\u1eb7c x\u00f3a ch\u1ec9 \u1edf nh\u1eefng n\u01a1i c\u1ea7n thi\u1ebft v\u1ec1 m\u1eb7t logic.<\/li>\n<li>S\u1eed d\u1ee5ng <code>RESTRICT<\/code> ho\u1eb7c <code>NO ACTION<\/code>\u0111\u1ec3 ch\u1eb7n c\u00e1c thay \u0111\u1ed5i c\u00f3 th\u1ec3 ph\u00e1 v\u1ee1 m\u1ed1i quan h\u1ec7.<\/li>\n<\/ul>\n<h3>2. Qu\u1ea3n l\u00fd giao d\u1ecbch<\/h3>\n<p>Bao b\u1ecdc t\u1ea5t c\u1ea3 c\u00e1c b\u01b0\u1edbc di chuy\u1ec3n d\u1eef li\u1ec7u trong c\u00e1c giao d\u1ecbch. \u0110i\u1ec1u n\u00e0y \u0111\u1ea3m b\u1ea3o r\u1eb1ng ho\u1eb7c t\u1ea5t c\u1ea3 c\u00e1c thay \u0111\u1ed5i \u0111\u1ec1u \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng, ho\u1eb7c kh\u00f4ng c\u00f3 thay \u0111\u1ed5i n\u00e0o \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng. C\u00e1c c\u1eadp nh\u1eadt t\u1eebng ph\u1ea7n d\u1eabn \u0111\u1ebfn tr\u1ea1ng th\u00e1i kh\u00f4ng nh\u1ea5t qu\u00e1n.<\/p>\n<ul>\n<li>B\u1eaft \u0111\u1ea7u m\u1ed9t giao d\u1ecbch tr\u01b0\u1edbc l\u1ec7nh DDL \u0111\u1ea7u ti\u00ean.<\/li>\n<li>Ch\u1ec9 commit sau khi t\u1ea5t c\u1ea3 c\u00e1c ki\u1ec3m tra x\u00e1c th\u1ef1c \u0111\u1ec1u v\u01b0\u1ee3t qua.<\/li>\n<li>Ho\u00e0n t\u00e1c ngay l\u1eadp t\u1ee9c n\u1ebfu x\u1ea3y ra l\u1ed7i.<\/li>\n<\/ul>\n<h3>3. C\u00e1c t\u1eadp l\u1ec7nh x\u00e1c minh d\u1eef li\u1ec7u<\/h3>\n<p>Sau khi di chuy\u1ec3n, ch\u1ea1y c\u00e1c t\u1eadp l\u1ec7nh \u0111\u1ec3 x\u00e1c minh d\u1eef li\u1ec7u.<\/p>\n<ul>\n<li>So s\u00e1nh s\u1ed1 l\u01b0\u1ee3ng h\u00e0ng gi\u1eefa b\u1ea3ng c\u0169 v\u00e0 b\u1ea3ng m\u1edbi.<\/li>\n<li>T\u00ednh to\u00e1n t\u1ed5ng ki\u1ec3m tra tr\u00ean c\u00e1c c\u1ed9t quan tr\u1ecdng \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o s\u1ef1 kh\u1edbp ch\u00ednh x\u00e1c.<\/li>\n<li>Ki\u1ec3m tra c\u00e1c gi\u00e1 tr\u1ecb null trong c\u00e1c c\u1ed9t t\u1eebng kh\u00f4ng \u0111\u01b0\u1ee3c ph\u00e9p l\u00e0 null.<\/li>\n<li>X\u00e1c minh r\u1eb1ng t\u1ea5t c\u1ea3 c\u00e1c r\u00e0ng bu\u1ed9c duy nh\u1ea5t \u0111\u1ec1u \u0111\u01b0\u1ee3c \u0111\u00e1p \u1ee9ng.<\/li>\n<\/ul>\n<h2>\u26a0\ufe0f Nh\u1eefng sai l\u1ea7m ph\u1ed5 bi\u1ebfn v\u00e0 gi\u1ea3i ph\u00e1p<\/h2>\n<p>Ngay c\u1ea3 khi l\u00ean k\u1ebf ho\u1ea1ch c\u1ea9n th\u1eadn, v\u1eabn c\u00f3 th\u1ec3 x\u1ea3y ra v\u1ea5n \u0111\u1ec1. D\u1ef1 \u0111o\u00e1n tr\u01b0\u1edbc nh\u1eefng v\u1ea5n \u0111\u1ec1 n\u00e0y s\u1ebd gi\u1ea3m th\u1eddi gian ng\u1eebng ho\u1ea1t \u0111\u1ed9ng.<\/p>\n<h3>1. V\u1ea5n \u0111\u1ec1 &#8220;Chia t\u00e1ch&#8221;<\/h3>\n<p>Khi chia t\u00e1ch m\u1ed9t b\u1ea3ng, b\u1ea1n c\u00f3 th\u1ec3 g\u1eb7p ph\u1ea3i c\u00e1c kh\u00f3a tr\u00f9ng l\u1eb7p. N\u1ebfu \u0111ang chia t\u00e1ch m\u1ed9t kh\u00f3a t\u1ed5ng h\u1ee3p, h\u00e3y \u0111\u1ea3m b\u1ea3o c\u00e1c kh\u00f3a m\u1edbi duy tr\u00ec t\u00ednh duy nh\u1ea5t trong c\u1ea5u tr\u00fac m\u1edbi.<\/p>\n<ul>\n<li><strong>Gi\u1ea3i ph\u00e1p:<\/strong>S\u1eed d\u1ee5ng c\u00e1c b\u1ea3ng t\u1ea1m \u0111\u1ec3 s\u1eafp x\u1ebfp l\u1ea1i d\u1eef li\u1ec7u tr\u01b0\u1edbc khi \u00e1p d\u1ee5ng l\u01b0\u1ee3c \u0111\u1ed3 m\u1edbi.<\/li>\n<\/ul>\n<h3>2. Hi\u1ec7u su\u1ea5t ch\u1ec9 m\u1ee5c<\/h3>\n<p>C\u00e1c m\u1ed1i quan h\u1ec7 m\u1edbi y\u00eau c\u1ea7u c\u00e1c ch\u1ec9 m\u1ee5c m\u1edbi. Kh\u00f4ng c\u00f3 ch\u00fang, c\u00e1c truy v\u1ea5n tr\u00ean c\u00e1c b\u1ea3ng li\u00ean k\u1ebft m\u1edbi s\u1ebd ch\u1eadm.<\/p>\n<ul>\n<li><strong>Gi\u1ea3i ph\u00e1p:<\/strong>T\u1ea1o ch\u1ec9 m\u1ee5c tr\u00ean c\u00e1c c\u1ed9t kh\u00f3a ngo\u1ea1i ngay l\u1eadp t\u1ee9c sau khi t\u1ea1o. Kh\u00f4ng n\u00ean ch\u1ec9 d\u1ef1a v\u00e0o ch\u1ec9 m\u1ee5c kh\u00f3a ch\u00ednh.<\/li>\n<\/ul>\n<h3>3. S\u1ef1 kh\u00f4ng kh\u1edbp gi\u1eefa m\u00e3 \u1ee9ng d\u1ee5ng<\/h3>\n<p>C\u01a1 s\u1edf d\u1eef li\u1ec7u thay \u0111\u1ed5i, nh\u01b0ng m\u00e3 \u1ee9ng d\u1ee5ng kh\u00f4ng \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt ngay l\u1eadp t\u1ee9c. \u0110i\u1ec1u n\u00e0y d\u1eabn \u0111\u1ebfn l\u1ed7i th\u1eddi gian ch\u1ea1y.<\/p>\n<ul>\n<li><strong>Gi\u1ea3i ph\u00e1p:<\/strong>Th\u1ef1c hi\u1ec7n c\u1edd t\u00ednh n\u0103ng ho\u1eb7c chi\u1ebfn l\u01b0\u1ee3c ghi \u0111\u00f4i trong giai \u0111o\u1ea1n chuy\u1ec3n ti\u1ebfp. Cho ph\u00e9p l\u01b0\u1ee3c \u0111\u1ed3 c\u0169 v\u00e0 m\u1edbi t\u1ed3n t\u1ea1i song song trong th\u1eddi gian ng\u1eafn.<\/li>\n<\/ul>\n<h3>4. Kh\u00e1c bi\u1ec7t ki\u1ec3u d\u1eef li\u1ec7u<\/h3>\n<p>T\u00e1i c\u1ea5u tr\u00fac th\u01b0\u1eddng bao g\u1ed3m vi\u1ec7c thay \u0111\u1ed5i ki\u1ec3u d\u1eef li\u1ec7u (v\u00ed d\u1ee5: VARCHAR th\u00e0nh INT). N\u1ebfu d\u1eef li\u1ec7u ch\u1ee9a k\u00fd t\u1ef1 kh\u00f4ng ph\u1ea3i s\u1ed1 trong tr\u01b0\u1eddng \u0111ang \u0111\u01b0\u1ee3c chuy\u1ec3n \u0111\u1ed5i, qu\u00e1 tr\u00ecnh di chuy\u1ec3n s\u1ebd th\u1ea5t b\u1ea1i.<\/p>\n<ul>\n<li><strong>Gi\u1ea3i ph\u00e1p:<\/strong>L\u00e0m s\u1ea1ch d\u1eef li\u1ec7u trong b\u01b0\u1edbc ti\u1ec1n di chuy\u1ec3n. T\u1ea1o b\u00e1o c\u00e1o d\u1eef li\u1ec7u kh\u00f4ng h\u1ee3p l\u1ec7 \u0111\u1ec3 xem x\u00e9t th\u1ee7 c\u00f4ng.<\/li>\n<\/ul>\n<h2>\ud83d\ude80 X\u00e1c minh sau khi t\u00e1i c\u1ea5u tr\u00fac<\/h2>\n<p>C\u00f4ng vi\u1ec7c ch\u01b0a k\u1ebft th\u00fac khi script di chuy\u1ec3n ho\u00e0n t\u1ea5t. H\u1ec7 th\u1ed1ng ph\u1ea3i \u0111\u01b0\u1ee3c x\u00e1c minh trong m\u00f4i tr\u01b0\u1eddng gi\u1ed1ng nh\u01b0 s\u1ea3n xu\u1ea5t.<\/p>\n<ul>\n<li><strong>\u0110o l\u01b0\u1eddng hi\u1ec7u n\u0103ng:<\/strong>Ch\u1ea1y c\u00f9ng b\u1ed9 truy v\u1ea5n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong ki\u1ec3m tra c\u01a1 s\u1edf. So s\u00e1nh th\u1eddi gian th\u1ef1c thi v\u00e0 s\u1eed d\u1ee5ng t\u00e0i nguy\u00ean.<\/li>\n<li><strong>Ki\u1ec3m th\u1eed ch\u1ea5p nh\u1eadn ng\u01b0\u1eddi d\u00f9ng:<\/strong>Cho ng\u01b0\u1eddi d\u00f9ng \u1ee9ng d\u1ee5ng th\u1ef1c hi\u1ec7n c\u00e1c quy tr\u00ecnh ti\u00eau chu\u1ea9n \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c ph\u1ea3n \u00e1nh \u0111\u00fang trong giao di\u1ec7n ng\u01b0\u1eddi d\u00f9ng.<\/li>\n<li><strong>Thi\u1ebft l\u1eadp gi\u00e1m s\u00e1t:<\/strong>B\u1eadt ghi nh\u1eadt k\u00fd n\u00e2ng cao v\u00e0 gi\u00e1m s\u00e1t cho c\u00e1c b\u1ea3ng c\u1ee5 th\u1ec3 tham gia. Theo d\u00f5i c\u00e1c \u0111\u1ee3t t\u0103ng \u0111\u1ed9t bi\u1ebfn l\u1ed7i ho\u1eb7c \u0111\u1ed9 tr\u1ec5.<\/li>\n<li><strong>C\u1eadp nh\u1eadt t\u00e0i li\u1ec7u:<\/strong>C\u1eadp nh\u1eadt s\u01a1 \u0111\u1ed3 ERD, t\u1eeb \u0111i\u1ec3n d\u1eef li\u1ec7u v\u00e0 t\u00e0i li\u1ec7u API \u0111\u1ec3 ph\u1ea3n \u00e1nh c\u1ea5u tr\u00fac m\u1edbi.<\/li>\n<\/ul>\n<h2>\ud83d\udcdd Ma tr\u1eadn \u0111\u00e1nh gi\u00e1 r\u1ee7i ro<\/h2>\n<table>\n<thead>\n<tr>\n<th>Y\u1ebfu t\u1ed1 r\u1ee7i ro<\/th>\n<th>T\u00e1c \u0111\u1ed9ng<\/th>\n<th>Chi\u1ebfn l\u01b0\u1ee3c gi\u1ea3m thi\u1ec3u<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>M\u1ea5t d\u1eef li\u1ec7u b\u1ea5t ng\u1edd<\/td>\n<td>Nghi\u00eam tr\u1ecdng<\/td>\n<td>X\u00e1c minh b\u1ea3n sao l\u01b0u tr\u01b0\u1edbc khi b\u1eaft \u0111\u1ea7u; s\u1eed d\u1ee5ng giao d\u1ecbch<\/td>\n<\/tr>\n<tr>\n<td>Th\u1eddi gian ng\u1eebng ho\u1ea1t \u0111\u1ed9ng<\/td>\n<td>Cao<\/td>\n<td>L\u00ean l\u1ecbch trong th\u1eddi gian b\u1ea3o tr\u00ec; s\u1eed d\u1ee5ng tri\u1ec3n khai xanh-\u0111\u1ecf<\/td>\n<\/tr>\n<tr>\n<td>Suy gi\u1ea3m hi\u1ec7u su\u1ea5t<\/td>\n<td>Trung b\u00ecnh<\/td>\n<td>Ki\u1ec3m th\u1eed v\u1edbi d\u1eef li\u1ec7u k\u00edch th\u01b0\u1edbc s\u1ea3n xu\u1ea5t; t\u1ed1i \u01b0u h\u00f3a ch\u1ec9 m\u1ee5c<\/td>\n<\/tr>\n<tr>\n<td>H\u1ecfng \u1ee9ng d\u1ee5ng<\/td>\n<td>Cao<\/td>\n<td>C\u1edd t\u00ednh n\u0103ng; tri\u1ec3n khai d\u1ea7n d\u1ea7n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>T\u00e1i c\u1ea5u tr\u00fac s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 l\u00e0 m\u1ed9t nhi\u1ec7m v\u1ee5 k\u1ef9 thu\u1eadt c\u00f3 k\u1ef7 lu\u1eadt. N\u00f3 \u0111\u00f2i h\u1ecfi s\u1ef1 c\u00e2n b\u1eb1ng gi\u1eefa c\u00e1c nguy\u00ean t\u1eafc m\u00f4 h\u00ecnh h\u00f3a d\u1eef li\u1ec7u l\u00fd thuy\u1ebft v\u00e0 c\u00e1c gi\u1edbi h\u1ea1n th\u1ef1c t\u1ebf v\u1ec1 v\u1eadn h\u00e0nh. B\u1eb1ng c\u00e1ch tu\u00e2n theo m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p c\u00f3 c\u1ea5u tr\u00fac, duy tr\u00ec c\u00e1c ki\u1ec3m tra nghi\u00eam ng\u1eb7t v\u1ec1 t\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u v\u00e0 chu\u1ea9n b\u1ecb k\u1ef9 l\u01b0\u1ee1ng cho qu\u00e1 tr\u00ecnh chuy\u1ec3n \u0111\u1ed5i, b\u1ea1n c\u00f3 th\u1ec3 hi\u1ec7n \u0111\u1ea1i h\u00f3a ki\u1ebfn tr\u00fac d\u1eef li\u1ec7u c\u1ee7a m\u00ecnh m\u00e0 kh\u00f4ng l\u00e0m \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn \u0111\u1ed9 tin c\u1eady c\u1ee7a c\u00e1c t\u00e0i s\u1ea3n th\u00f4ng tin.<\/p>\n<p>\u0110\u1ed9 ph\u1ee9c t\u1ea1p c\u1ee7a c\u00e1c h\u1ec7 th\u1ed1ng hi\u1ec7n \u0111\u1ea1i \u0111\u00f2i h\u1ecfi ch\u00fang ta ph\u1ea3i lu\u00f4n c\u1ea3nh gi\u00e1c. Vi\u1ec7c xem x\u00e9t \u0111\u1ecbnh k\u1ef3 s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 n\u00ean l\u00e0 m\u1ed9t ph\u1ea7n trong chu tr\u00ecnh ph\u00e1t tri\u1ec3n \u0111\u1ec3 ng\u0103n ch\u1eb7n t\u00ecnh tr\u1ea1ng ph\u00e1t tri\u1ec3n qu\u00e1 m\u1ee9c tr\u1edf th\u00e0nh v\u1ea5n \u0111\u1ec1 nghi\u00eam tr\u1ecdng m\u1ed9t l\u1ea7n n\u1eefa. H\u00e3y coi s\u01a1 \u0111\u1ed3 l\u00e0 m\u1ed9t th\u00e0nh ph\u1ea7n then ch\u1ed1t trong h\u1ea1 t\u1ea7ng \u1ee9ng d\u1ee5ng, x\u1ee9ng \u0111\u00e1ng \u0111\u01b0\u1ee3c ch\u0103m s\u00f3c v\u00e0 quan t\u00e2m nh\u01b0 ch\u00ednh m\u00e3 ngu\u1ed3n.<\/p>\n<p>Th\u00e0nh c\u00f4ng trong n\u1ed7 l\u1ef1c n\u00e0y \u0111\u01b0\u1ee3c \u0111o b\u1eb1ng \u0111\u1ed9 \u1ed5n \u0111\u1ecbnh c\u1ee7a h\u1ec7 th\u1ed1ng sau khi di d\u1eddi v\u00e0 \u0111\u1ed9 ch\u00ednh x\u00e1c li\u00ean t\u1ee5c c\u1ee7a d\u1eef li\u1ec7u m\u00e0 n\u00f3 l\u01b0u gi\u1eef. V\u1edbi s\u1ef1 ki\u00ean nh\u1eabn v\u00e0 ch\u00ednh x\u00e1c, con \u0111\u01b0\u1eddng d\u1eabn \u0111\u1ebfn m\u1ed9t c\u1ea5u tr\u00fac c\u01a1 s\u1edf d\u1eef li\u1ec7u s\u1ea1ch s\u1ebd v\u00e0 hi\u1ec7u qu\u1ea3 h\u01a1n l\u00e0 ho\u00e0n to\u00e0n kh\u1ea3 thi.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>C\u00e1c l\u01b0\u1ee3c \u0111\u1ed3 c\u01a1 s\u1edf d\u1eef li\u1ec7u l\u00e0 nh\u1eefng t\u00e1c ph\u1ea9m s\u1ed1ng \u0111\u1ed9ng. Ch\u00fang ph\u00e1t tri\u1ec3n song song v\u1edbi logic kinh doanh m\u00e0 ch\u00fang h\u1ed7 tr\u1ee3. Theo th\u1eddi gian, khi&hellip;<\/p>\n","protected":false},"author":1,"featured_media":1648,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_yoast_wpseo_title":"T\u00e1i c\u1ea5u tr\u00fac s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 m\u00e0 kh\u00f4ng m\u1ea5t d\u1eef li\u1ec7u | H\u01b0\u1edbng d\u1eabn nhanh \ud83d\udee0\ufe0f","_yoast_wpseo_metadesc":"H\u1ecdc c\u00e1ch t\u00e1i c\u1ea5u tr\u00fac c\u00e1c s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 b\u1ecb qu\u00e1 t\u1ea3i m\u1ed9t c\u00e1ch an to\u00e0n. Ng\u0103n ng\u1eeba m\u1ea5t d\u1eef li\u1ec7u, chu\u1ea9n h\u00f3a l\u01b0\u1ee3c \u0111\u1ed3 v\u00e0 \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n v\u1edbi h\u01b0\u1edbng d\u1eabn t\u1eebng b\u01b0\u1edbc n\u00e0y.","fifu_image_url":"","fifu_image_alt":"","footnotes":""},"categories":[68],"tags":[89,92],"class_list":["post-1647","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-database-design","tag-academic","tag-erd"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.1.1 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>T\u00e1i c\u1ea5u tr\u00fac s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 m\u00e0 kh\u00f4ng m\u1ea5t d\u1eef li\u1ec7u | H\u01b0\u1edbng d\u1eabn nhanh \ud83d\udee0\ufe0f<\/title>\n<meta name=\"description\" content=\"H\u1ecdc c\u00e1ch t\u00e1i c\u1ea5u tr\u00fac c\u00e1c s\u01a1 \u0111\u1ed3 quan h\u1ec7 th\u1ef1c th\u1ec3 b\u1ecb qu\u00e1 t\u1ea3i m\u1ed9t c\u00e1ch an to\u00e0n. 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