{"id":28398,"date":"2025-07-21T09:20:55","date_gmt":"2025-07-21T02:20:55","guid":{"rendered":"https:\/\/interdata.vn\/blog\/?p=28398"},"modified":"2025-07-24T09:26:29","modified_gmt":"2025-07-24T02:26:29","slug":"structured-query-language-sql-la-gi","status":"publish","type":"post","link":"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/","title":{"rendered":"SQL L\u00e0 G\u00ec? H\u1ecdc SQL C\u00f3 Kh\u00f3 Kh\u00f4ng? [H\u01b0\u1edbng D\u1eabn Cho Ng\u01b0\u1eddi M\u1edbi]"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-white ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">N\u1ed8I DUNG<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#SQL-la-gi\" >SQL l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Tai-sao-SQL-lai-quan-trong\" >T\u1ea1i sao SQL l\u1ea1i quan tr\u1ecdng?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Lich-su-cua-SQL\" >L\u1ecbch s\u1eed c\u1ee7a SQL<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Mot-he-thong-SQL-gom-nhung-thanh-phan-gi\" >M\u1ed9t h\u1ec7 th\u1ed1ng SQL g\u1ed3m nh\u1eefng th\u00e0nh ph\u1ea7n g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#SQL-hoat-dong-nhu-the-nao\" >SQL ho\u1ea1t \u0111\u1ed9ng nh\u01b0 th\u1ebf n\u00e0o?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#1-Truy-van\" >1. Truy v\u1ea5n<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#2-Phan-tich-cu-phap\" >2. Ph\u00e2n t\u00edch c\u00fa ph\u00e1p<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#3-Toi-uu-hoa\" >3. T\u1ed1i \u01b0u h\u00f3a<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#4-Thuc-thi\" >4. Th\u1ef1c thi<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Cac-loai-cau-lenh-SQL\" >C\u00e1c lo\u1ea1i c\u00e2u l\u1ec7nh SQL<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Tieu-chuan-SQL-la-gi\" >Ti\u00eau chu\u1ea9n SQL l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Hanh-dong-dua-SQL-vao-la-gi\" >H\u00e0nh \u0111\u1ed9ng \u0111\u01b0a SQL v\u00e0o l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#MySQL-la-gi\" >MySQL l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#NoSQL-la-gi\" >NoSQL l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#May-chu-SQL-la-gi\" >M\u00e1y ch\u1ee7 SQL l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Ly-do-ban-nen-hoc-SQL\" >L\u00fd do b\u1ea1n n\u00ean h\u1ecdc SQL<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/interdata.vn\/blog\/structured-query-language-sql-la-gi\/#Hoc-SQL-bat-dau-tu-dau\" >H\u1ecdc SQL b\u1eaft \u0111\u1ea7u t\u1eeb \u0111\u00e2u?<\/a><\/li><\/ul><\/nav><\/div>\n<p>Trong b\u1ed1i c\u1ea3nh m\u1ecdi quy\u1ebft \u0111\u1ecbnh kinh doanh \u0111\u1ec1u d\u1ef1a v\u00e0o d\u1eef li\u1ec7u, vi\u1ec7c hi\u1ec3u v\u00e0 s\u1eed d\u1ee5ng SQL kh\u00f4ng c\u00f2n l\u00e0 l\u1ef1a ch\u1ecdn m\u00e0 l\u00e0 m\u1ed9t y\u00eau c\u1ea7u t\u1ea5t y\u1ebfu. SQL ch\u00ednh l\u00e0 c\u00f4ng c\u1ee5 gi\u00fap khai th\u00e1c th\u00f4ng tin t\u1eeb d\u1eef li\u1ec7u th\u00f4. C\u00f9ng InterData t\u00ecm hi\u1ec3u <strong>ng\u00f4n ng\u1eef SQL l\u00e0 g\u00ec<\/strong>, <strong>c\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng<\/strong>, <strong>s\u1ef1 kh\u00e1c bi\u1ec7t v\u1edbi <a href=\"https:\/\/interdata.vn\/blog\/mysql-la-gi\/\">MySQL<\/a> hay NoSQL<\/strong>, v\u00e0 cung c\u1ea5p m\u1ed9t <strong>l\u1ed9 tr\u00ecnh h\u1ecdc SQL r\u00f5 r\u00e0ng<\/strong> \u0111\u1ec3 b\u1ea1n b\u1eaft \u0111\u1ea7u h\u1ecdc k\u1ef9 n\u0103ng quan tr\u1ecdng n\u00e0y.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"SQL-la-gi\"><\/span>SQL l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>SQL, vi\u1ebft t\u1eaft c\u1ee7a <strong>Structured Query Language<\/strong> (Ng\u00f4n ng\u1eef truy v\u1ea5n c\u00f3 c\u1ea5u tr\u00fac), l\u00e0 m\u1ed9t ng\u00f4n ng\u1eef ti\u00eau chu\u1ea9n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 giao ti\u1ebfp v\u1edbi c\u01a1 s\u1edf d\u1eef li\u1ec7u.<\/p>\n<p>H\u00e3y h\u00ecnh dung c\u01a1 s\u1edf d\u1eef li\u1ec7u nh\u01b0 m\u1ed9t nh\u00e0 kho kh\u1ed5ng l\u1ed3 ch\u1ee9a h\u00e0ng tri\u1ec7u h\u1ed3 s\u01a1 \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp trong c\u00e1c t\u1ee7 t\u00e0i li\u1ec7u. SQL ch\u00ednh l\u00e0 ng\u00f4n ng\u1eef b\u1ea1n d\u00f9ng \u0111\u1ec3 ra l\u1ec7nh cho ng\u01b0\u1eddi qu\u1ea3n l\u00fd kho (<a href=\"https:\/\/interdata.vn\/blog\/he-quan-tri-co-so-du-lieu-la-gi\/\">h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u<\/a>) t\u00ecm ki\u1ebfm, l\u1ea5y ra, c\u1eadp nh\u1eadt ho\u1eb7c c\u1ea5t th\u00eam h\u1ed3 s\u01a1 m\u1edbi.<\/p>\n<p>\u0110i\u1ec1u quan tr\u1ecdng c\u1ea7n l\u00e0m r\u00f5: SQL l\u00e0 m\u1ed9t ng\u00f4n ng\u1eef truy v\u1ea5n, kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh \u0111a n\u0103ng nh\u01b0 Python hay <a href=\"https:\/\/interdata.vn\/blog\/ngon-ngu-lap-trinh-java\/\">Java<\/a>. Ch\u1ee9c n\u0103ng ch\u00ednh c\u1ee7a SQL t\u1eadp trung ho\u00e0n to\u00e0n v\u00e0o vi\u1ec7c qu\u1ea3n l\u00fd v\u00e0 thao t\u00e1c d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong m\u1ed9t c\u01a1 s\u1edf d\u1eef li\u1ec7u quan h\u1ec7, n\u01a1i d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c t\u1ed5 ch\u1ee9c th\u00e0nh c\u00e1c b\u1ea3ng c\u00f3 c\u1ea5u tr\u00fac r\u00f5 r\u00e0ng.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-la-gi-1.jpg\" alt=\"SQL l\u00e0 g\u00ec\" width=\"600\" height=\"400\" class=\"aligncenter size-full wp-image-30033\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-la-gi-1.jpg 600w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-la-gi-1-300x200.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Tai-sao-SQL-lai-quan-trong\"><\/span>T\u1ea1i sao SQL l\u1ea1i quan tr\u1ecdng?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>SQL (Structured Query Language &#8211; Ng\u00f4n ng\u1eef truy v\u1ea5n c\u00f3 c\u1ea5u tr\u00fac) quan tr\u1ecdng v\u00ec n\u00f3 l\u00e0 ng\u00f4n ng\u1eef chu\u1ea9n \u0111\u1ec3 qu\u1ea3n l\u00fd, truy c\u1eadp v\u00e0 thao t\u00e1c d\u1eef li\u1ec7u trong c\u01a1 s\u1edf d\u1eef li\u1ec7u quan h\u1ec7 m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3, nhanh ch\u00f3ng v\u00e0 ch\u00ednh x\u00e1c.<\/p>\n<p>SQL cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng th\u1ef1c hi\u1ec7n c\u00e1c t\u00e1c v\u1ee5 nh\u01b0 l\u01b0u tr\u1eef, c\u1eadp nh\u1eadt, x\u00f3a v\u00e0 truy v\u1ea5n d\u1eef li\u1ec7u l\u1edbn v\u00e0 ph\u1ee9c t\u1ea1p m\u1ed9t c\u00e1ch d\u1ec5 d\u00e0ng m\u00e0 kh\u00f4ng c\u1ea7n ph\u1ea3i l\u00e0 chuy\u00ean gia v\u1ec1 l\u1eadp tr\u00ecnh.<\/p>\n<p>Nh\u1edd v\u00e0o \u0111\u00f3, SQL gi\u00fap t\u1ed1i \u01b0u h\u00f3a hi\u1ec7u su\u1ea5t c\u1ee7a h\u1ec7 th\u1ed1ng c\u01a1 s\u1edf d\u1eef li\u1ec7u, \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n v\u00e0 nh\u1ea5t qu\u00e1n d\u1eef li\u1ec7u, \u0111\u1ed3ng th\u1eddi h\u1ed7 tr\u1ee3 ph\u00e2n t\u00edch d\u1eef li\u1ec7u v\u00e0 ra quy\u1ebft \u0111\u1ecbnh d\u1ef1a tr\u00ean d\u1eef li\u1ec7u trong nhi\u1ec1u l\u0129nh v\u1ef1c nh\u01b0 doanh nghi\u1ec7p, khoa h\u1ecdc d\u1eef li\u1ec7u, ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m, v\u00e0 qu\u1ea3n tr\u1ecb h\u1ec7 th\u1ed1ng.<\/p>\n<p>Quan tr\u1ecdng c\u00f2n n\u1eb1m \u1edf t\u00ednh linh ho\u1ea1t v\u00e0 ph\u1ed5 bi\u1ebfn r\u1ed9ng r\u00e3i:<\/p>\n<ul>\n<li>SQL x\u1eed l\u00fd truy v\u1ea5n r\u1ea5t nhanh, c\u00f3 th\u1ec3 thao t\u00e1c v\u1edbi h\u00e0ng tri\u1ec7u b\u1ea3n ghi trong v\u00e0i gi\u00e2y nh\u1edd c\u01a1 ch\u1ebf t\u1ed1i \u01b0u h\u00f3a c\u1ee7a h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u.<\/li>\n<li>N\u00f3 l\u00e0 c\u1ea7u n\u1ed1i gi\u1eefa c\u00e1c \u1ee9ng d\u1ee5ng (nh\u01b0 web, ph\u1ea7n m\u1ec1m) v\u00e0 c\u01a1 s\u1edf d\u1eef li\u1ec7u, gi\u00fap t\u1ef1 \u0111\u1ed9ng h\u00f3a vi\u1ec7c truy xu\u1ea5t v\u00e0 c\u1eadp nh\u1eadt th\u00f4ng tin.<\/li>\n<li>SQL \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf v\u1edbi c\u00fa ph\u00e1p g\u1ea7n g\u0169i ti\u1ebfng Anh, d\u1ec5 h\u1ecdc v\u00e0 \u00e1p d\u1ee5ng cho c\u1ea3 ng\u01b0\u1eddi kh\u00f4ng chuy\u00ean v\u1ec1 CNTT.<\/li>\n<li>T\u00ednh n\u0103ng giao d\u1ecbch h\u1ed7 tr\u1ee3 gi\u1eef cho d\u1eef li\u1ec7u lu\u00f4n nh\u1ea5t qu\u00e1n v\u00e0 an to\u00e0n k\u1ec3 c\u1ea3 khi x\u1ea3y ra l\u1ed7i h\u1ec7 th\u1ed1ng (ACID).<\/li>\n<li>Gi\u00fap doanh nghi\u1ec7p v\u00e0 t\u1ed5 ch\u1ee9c ra quy\u1ebft \u0111\u1ecbnh d\u1ef1a tr\u00ean d\u1eef li\u1ec7u ch\u00ednh x\u00e1c, n\u00e2ng cao hi\u1ec7u qu\u1ea3 kinh doanh v\u00e0 v\u1eadn h\u00e0nh.<\/li>\n<\/ul>\n<p>T\u00f3m l\u1ea1i, SQL l\u00e0 n\u1ec1n t\u1ea3ng quan tr\u1ecdng trong qu\u1ea3n l\u00fd d\u1eef li\u1ec7u hi\u1ec7n \u0111\u1ea1i, thi\u1ebft y\u1ebfu v\u1edbi m\u1ecdi c\u00f4ng vi\u1ec7c li\u00ean quan \u0111\u1ebfn ph\u00e2n t\u00edch, x\u1eed l\u00fd d\u1eef li\u1ec7u, ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m v\u00e0 qu\u1ea3n tr\u1ecb h\u1ec7 th\u1ed1ng.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-01.jpg\" alt=\"SQL\" width=\"600\" height=\"399\" class=\"aligncenter size-full wp-image-30028\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-01.jpg 600w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-01-300x200.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Lich-su-cua-SQL\"><\/span>L\u1ecbch s\u1eed c\u1ee7a SQL<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>SQL c\u00f3 m\u1ed9t l\u1ecbch s\u1eed l\u00e2u d\u00e0i v\u00e0 \u1ed5n \u0111\u1ecbnh, n\u1ec1n t\u1ea3ng c\u1ee7a SQL b\u1eaft \u0111\u1ea7u t\u1eeb b\u00e0i b\u00e1o &#8220;A Relational Model of Data for Large Shared Data Banks&#8221; c\u1ee7a Edgar F. Codd v\u00e0o n\u0103m 1970.<\/p>\n<p>D\u1ef1a tr\u00ean m\u00f4 h\u00ecnh n\u00e0y, Donald D. Chamberlin v\u00e0 Raymond F. Boyce t\u1ea1i IBM \u0111\u00e3 ph\u00e1t tri\u1ec3n ng\u00f4n ng\u1eef SEQUEL, sau n\u00e0y \u0111\u01b0\u1ee3c r\u00fat g\u1ecdn th\u00e0nh SQL. Phi\u00ean b\u1ea3n th\u01b0\u01a1ng m\u1ea1i \u0111\u1ea7u ti\u00ean \u0111\u01b0\u1ee3c ph\u00e1t h\u00e0nh b\u1edfi Relational Software (nay l\u00e0 Oracle) v\u00e0o n\u0103m 1979.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Mot-he-thong-SQL-gom-nhung-thanh-phan-gi\"><\/span>M\u1ed9t h\u1ec7 th\u1ed1ng SQL g\u1ed3m nh\u1eefng th\u00e0nh ph\u1ea7n g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>M\u1ed9t h\u1ec7 th\u1ed1ng SQL (h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u s\u1eed d\u1ee5ng ng\u00f4n ng\u1eef truy v\u1ea5n c\u00f3 c\u1ea5u tr\u00fac) th\u01b0\u1eddng g\u1ed3m c\u00e1c th\u00e0nh ph\u1ea7n ch\u00ednh sau:<\/p>\n<ul>\n<li><strong>Database Engine<\/strong>: L\u00e0 th\u00e0nh ph\u1ea7n c\u1ed1t l\u00f5i, ch\u1ecbu tr\u00e1ch nhi\u1ec7m l\u01b0u tr\u1eef, qu\u1ea3n l\u00fd, x\u1eed l\u00fd d\u1eef li\u1ec7u trong c\u01a1 s\u1edf d\u1eef li\u1ec7u; bao g\u1ed3m qu\u1ea3n l\u00fd b\u1ea3ng, ch\u1ec9 m\u1ee5c, trang d\u1eef li\u1ec7u, giao d\u1ecbch, b\u1ea3o m\u1eadt, sao l\u01b0u v\u00e0 ph\u1ee5c h\u1ed3i.<\/li>\n<li><strong>SQL Language Processor<\/strong>: B\u1ed9 x\u1eed l\u00fd c\u00e2u l\u1ec7nh SQL, h\u1ed7 tr\u1ee3 th\u1ef1c hi\u1ec7n truy v\u1ea5n, thao t\u00e1c d\u1eef li\u1ec7u nh\u01b0 SELECT, INSERT, UPDATE, DELETE.<\/li>\n<li><strong>SQLOS (SQL Operating System)<\/strong>: T\u1ea7ng h\u1ed7 tr\u1ee3, x\u1eed l\u00fd c\u00e1c nhi\u1ec7m v\u1ee5 qu\u1ea3n l\u00fd t\u00e0i nguy\u00ean h\u1ec7 th\u1ed1ng nh\u01b0 <a href=\"https:\/\/interdata.vn\/blog\/memory-management-la-gi\/\">qu\u1ea3n l\u00fd b\u1ed9 nh\u1edb<\/a>, l\u00ean l\u1ecbch t\u00e1c v\u1ee5, x\u1eed l\u00fd kh\u00f3a tr\u00e1nh xung \u0111\u1ed9t trong giao d\u1ecbch.<\/li>\n<li><strong>External Protocols \/ Networking Layer<\/strong>: Giao ti\u1ebfp v\u1edbi c\u00e1c \u1ee9ng d\u1ee5ng b\u00ean ngo\u00e0i qua m\u1ea1ng, nh\u1eadn v\u00e0 x\u1eed l\u00fd c\u00e1c k\u1ebft n\u1ed1i, \u0111\u1ea3m b\u1ea3o truy\u1ec1n nh\u1eadn d\u1eef li\u1ec7u.<\/li>\n<li><strong>Management Tools<\/strong>: Management Tools l\u00e0 m\u1ed9t c\u00f4ng c\u1ee5 h\u1ed7 tr\u1ee3 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u, v\u00ed d\u1ee5 nh\u01b0 SQL Server Management Studio (SSMS) gi\u00fap qu\u1ea3n l\u00fd, gi\u00e1m s\u00e1t v\u00e0 \u0111i\u1ec1u khi\u1ec3n h\u1ec7 th\u1ed1ng SQL.<\/li>\n<\/ul>\n<p>Ngo\u00e0i ra, trong c\u1ea5u tr\u00fac c\u1ee7a SQL c\u00f2n c\u00f3:<\/p>\n<ul>\n<li><strong>Storage Engine<\/strong> qu\u1ea3n l\u00fd c\u00e1c t\u1ec7p d\u1eef li\u1ec7u v\u1eadt l\u00fd v\u00e0 nh\u1eadt k\u00fd giao d\u1ecbch.<\/li>\n<li><strong>Buffer Manager<\/strong> qu\u1ea3n l\u00fd b\u1ed9 nh\u1edb \u0111\u1ec7m d\u1eef li\u1ec7u.<\/li>\n<li><strong>Transaction Log<\/strong> ghi l\u1ea1i c\u00e1c thay \u0111\u1ed5i \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n giao d\u1ecbch.<\/li>\n<li><strong>Integration Services (SSIS)<\/strong>: C\u00f4ng c\u1ee5 d\u00f9ng \u0111\u1ec3 di chuy\u1ec3n, sao ch\u00e9p v\u00e0 chuy\u1ec3n \u0111\u1ed5i d\u1eef li\u1ec7u gi\u1eefa c\u00e1c ngu\u1ed3n kh\u00e1c nhau.<\/li>\n<li><strong>Analysis Services (SSAS)<\/strong>: C\u00f4ng c\u1ee5 d\u00f9ng \u0111\u1ec3 ph\u00e2n t\u00edch d\u1eef li\u1ec7u, th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng cho c\u00e1c \u1ee9ng d\u1ee5ng Business Intelligence (BI).<\/li>\n<li><strong>Notification Services<\/strong>: D\u1ecbch v\u1ee5 d\u00f9ng \u0111\u1ec3 t\u1ea1o v\u00e0 g\u1eedi c\u00e1c th\u00f4ng b\u00e1o t\u1ef1 \u0111\u1ed9ng d\u1ef1a tr\u00ean c\u00e1c s\u1ef1 ki\u1ec7n d\u1eef li\u1ec7u.<\/li>\n<li><strong><a href=\"https:\/\/interdata.vn\/blog\/dmarc-la-gi\/\">Reporting<\/a> Services (SSRS)<\/strong>: C\u00f4ng c\u1ee5 cho ph\u00e9p t\u1ea1o, qu\u1ea3n l\u00fd v\u00e0 tri\u1ec3n khai c\u00e1c b\u00e1o c\u00e1o \u0111a d\u1ea1ng.<\/li>\n<\/ul>\n<p>M\u1ed9t h\u1ec7 th\u1ed1ng SQL bao g\u1ed3m th\u00e0nh ph\u1ea7n x\u1eed l\u00fd d\u1eef li\u1ec7u trung t\u00e2m (Database Engine), <a href=\"https:\/\/interdata.vn\/blog\/he-dieu-hanh\/\">h\u1ec7 \u0111i\u1ec1u h\u00e0nh<\/a> h\u1ed7 tr\u1ee3 cho qu\u1ea3n l\u00fd t\u00e0i nguy\u00ean (SQLOS), giao th\u1ee9c m\u1ea1ng cho k\u1ebft n\u1ed1i b\u00ean ngo\u00e0i, c\u00f4ng c\u1ee5 qu\u1ea3n l\u00fd c\u00f9ng c\u00e1c d\u1ecbch v\u1ee5 t\u00edch h\u1ee3p ph\u1ee5 tr\u1ee3 nh\u1eb1m cung c\u1ea5p m\u1ed9t m\u00f4i tr\u01b0\u1eddng qu\u1ea3n tr\u1ecb v\u00e0 khai th\u00e1c d\u1eef li\u1ec7u ho\u00e0n ch\u1ec9nh, b\u1ec1n v\u1eefng v\u00e0 linh ho\u1ea1t<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-02.jpg\" alt=\"SQL\" width=\"600\" height=\"338\" class=\"aligncenter size-full wp-image-30029\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-02.jpg 600w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-02-300x169.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"SQL-hoat-dong-nhu-the-nao\"><\/span>SQL ho\u1ea1t \u0111\u1ed9ng nh\u01b0 th\u1ebf n\u00e0o?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Khi b\u1ea1n g\u1eedi m\u1ed9t c\u00e2u l\u1ec7nh SQL, DBMS s\u1ebd x\u1eed l\u00fd y\u00eau c\u1ea7u \u0111\u00f3 qua m\u1ed9t quy tr\u00ecnh g\u1ed3m 4 b\u01b0\u1edbc c\u01a1 b\u1ea3n \u0111\u1ec3 tr\u1ea3 v\u1ec1 k\u1ebft qu\u1ea3. Vi\u1ec7c hi\u1ec3u r\u00f5 quy tr\u00ecnh n\u00e0y gi\u00fap b\u1ea1n h\u00ecnh dung \u0111\u01b0\u1ee3c \u0111i\u1ec1u g\u00ec x\u1ea3y ra &#8220;ph\u00eda sau h\u1eadu tr\u01b0\u1eddng&#8221;.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-03.jpg\" alt=\"SQL\" width=\"600\" height=\"333\" class=\"aligncenter size-full wp-image-30030\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-03.jpg 600w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-03-300x167.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<h3><span class=\"ez-toc-section\" id=\"1-Truy-van\"><\/span>1. Truy v\u1ea5n<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u1ea7u ti\u00ean, \u1ee9ng d\u1ee5ng client (v\u00ed d\u1ee5: m\u1ed9t ph\u1ea7n m\u1ec1m ph\u00e2n t\u00edch, m\u1ed9t <a href=\"https:\/\/interdata.vn\/blog\/page-la-gi\/\">trang web<\/a>) g\u1eedi c\u00e2u l\u1ec7nh SQL \u0111\u1ebfn <a href=\"https:\/\/interdata.vn\/blog\/database-server-la-gi\/\">m\u00e1y ch\u1ee7 c\u01a1 s\u1edf d\u1eef li\u1ec7u<\/a>.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"2-Phan-tich-cu-phap\"><\/span>2. Ph\u00e2n t\u00edch c\u00fa ph\u00e1p<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Tr\u00ecnh ph\u00e2n t\u00edch c\u00fa ph\u00e1p (parser) trong DBMS s\u1ebd ti\u1ebfp nh\u1eadn c\u00e2u l\u1ec7nh. Qu\u00e1 tr\u00ecnh n\u00e0y ki\u1ec3m tra ba y\u1ebfu t\u1ed1: c\u00e2u l\u1ec7nh c\u00f3 \u0111\u00fang c\u00fa ph\u00e1p kh\u00f4ng, ng\u01b0\u1eddi d\u00f9ng c\u00f3 \u0111\u1ee7 quy\u1ec1n th\u1ef1c hi\u1ec7n h\u00e0nh \u0111\u1ed9ng n\u00e0y kh\u00f4ng, v\u00e0 c\u00e1c b\u1ea3ng, c\u1ed9t \u0111\u01b0\u1ee3c nh\u1eafc \u0111\u1ebfn c\u00f3 t\u1ed3n t\u1ea1i trong c\u01a1 s\u1edf d\u1eef li\u1ec7u kh\u00f4ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"3-Toi-uu-hoa\"><\/span>3. T\u1ed1i \u01b0u h\u00f3a<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Sau khi c\u00e2u l\u1ec7nh \u0111\u01b0\u1ee3c x\u00e1c th\u1ef1c, b\u1ed9 m\u00e1y t\u1ed1i \u01b0u h\u00f3a (optimizer) s\u1ebd ph\u00e2n t\u00edch v\u00e0 x\u00e1c \u0111\u1ecbnh k\u1ebf ho\u1ea1ch th\u1ef1c thi hi\u1ec7u qu\u1ea3 nh\u1ea5t. V\u00ed d\u1ee5, v\u1edbi m\u1ed9t truy v\u1ea5n ph\u1ee9c t\u1ea1p, n\u00f3 s\u1ebd quy\u1ebft \u0111\u1ecbnh n\u00ean qu\u00e9t b\u1ea3ng n\u00e0o tr\u01b0\u1edbc, s\u1eed d\u1ee5ng ch\u1ec9 m\u1ee5c (index) n\u00e0o \u0111\u1ec3 t\u0103ng t\u1ed1c \u0111\u1ed9 truy xu\u1ea5t.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"4-Thuc-thi\"><\/span>4. Th\u1ef1c thi<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Cu\u1ed1i c\u00f9ng, b\u1ed9 m\u00e1y th\u1ef1c thi (execution engine) s\u1ebd th\u1ef1c hi\u1ec7n k\u1ebf ho\u1ea1ch \u0111\u00e3 \u0111\u01b0\u1ee3c t\u1ed1i \u01b0u h\u00f3a. Qu\u00e1 tr\u00ecnh n\u00e0y bao g\u1ed3m vi\u1ec7c l\u1ea5y d\u1eef li\u1ec7u t\u1eeb b\u1ed9 nh\u1edb ho\u1eb7c \u0111\u0129a, x\u1eed l\u00fd v\u00e0 tr\u1ea3 k\u1ebft qu\u1ea3 v\u1ec1 cho \u1ee9ng d\u1ee5ng client \u0111\u00e3 g\u1eedi y\u00eau c\u1ea7u ban \u0111\u1ea7u.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cac-loai-cau-lenh-SQL\"><\/span>C\u00e1c lo\u1ea1i c\u00e2u l\u1ec7nh SQL<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>C\u00e1c c\u00e2u l\u1ec7nh SQL (Structured Query Language &#8211; Ng\u00f4n ng\u1eef truy v\u1ea5n c\u00f3 c\u1ea5u tr\u00fac) \u0111\u01b0\u1ee3c chia th\u00e0nh nhi\u1ec1u lo\u1ea1i ch\u00ednh, m\u1ed7i lo\u1ea1i ph\u1ee5c v\u1ee5 m\u1ee5c \u0111\u00edch s\u1eed d\u1ee5ng kh\u00e1c nhau trong qu\u1ea3n l\u00fd v\u00e0 thao t\u00e1c d\u1eef li\u1ec7u c\u1ee7a c\u01a1 s\u1edf d\u1eef li\u1ec7u quan h\u1ec7. C\u00e1c lo\u1ea1i c\u00e2u l\u1ec7nh SQL ph\u1ed5 bi\u1ebfn bao g\u1ed3m:<\/p>\n<table style=\"width: 100%; border-collapse: collapse; font-family: Arial, sans-serif; text-align: left;\">\n<thead>\n<tr style=\"background-color: #0d6efd; color: #fff;\">\n<th style=\"padding: 12px; border: 1px solid #cccccc; text-align: center;\"><span style=\"color: #ffffff;\">Lo\u1ea1i c\u00e2u l\u1ec7nh SQL<\/span><\/th>\n<th style=\"padding: 12px; border: 1px solid #cccccc; text-align: center;\"><span style=\"color: #ffffff;\">Ch\u1ee9c n\u0103ng ch\u00ednh<\/span><\/th>\n<th style=\"padding: 12px; border: 1px solid #cccccc; text-align: center;\"><span style=\"color: #ffffff;\">V\u00ed d\u1ee5 c\u00e1c c\u00e2u l\u1ec7nh<\/span><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background-color: #f9f9f9;\">\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">DDL (Data Definition Language) \u2013 Ng\u00f4n ng\u1eef \u0111\u1ecbnh ngh\u0129a d\u1eef li\u1ec7u<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">T\u1ea1o, thay \u0111\u1ed5i, x\u00f3a c\u1ea5u tr\u00fac c\u01a1 s\u1edf d\u1eef li\u1ec7u (b\u1ea3ng, database, ch\u1ec9 m\u1ee5c)<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">CREATE, ALTER, DROP, TRUNCATE<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">DML (Data Manipulation Language) \u2013 Ng\u00f4n ng\u1eef thao t\u00e1c d\u1eef li\u1ec7u<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">Th\u00eam, s\u1eeda, x\u00f3a d\u1eef li\u1ec7u trong b\u1ea3ng<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">INSERT, UPDATE, DELETE<\/span><\/td>\n<\/tr>\n<tr style=\"background-color: #f9f9f9;\">\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">DQL (Data Query Language) \u2013 Ng\u00f4n ng\u1eef truy v\u1ea5n d\u1eef li\u1ec7u<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">Truy v\u1ea5n, l\u1ea5y d\u1eef li\u1ec7u t\u1eeb b\u1ea3ng<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">SELECT<\/span><\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">DCL (Data Control Language) \u2013 Ng\u00f4n ng\u1eef ki\u1ec3m so\u00e1t d\u1eef li\u1ec7u<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">Qu\u1ea3n l\u00fd quy\u1ec1n truy c\u1eadp v\u00e0 ki\u1ec3m so\u00e1t ng\u01b0\u1eddi d\u00f9ng<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">GRANT, REVOKE<\/span><\/td>\n<\/tr>\n<tr style=\"background-color: #f9f9f9;\">\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">TCL (Transaction Control Language) \u2013 Ng\u00f4n ng\u1eef ki\u1ec3m so\u00e1t giao d\u1ecbch<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">Qu\u1ea3n l\u00fd giao d\u1ecbch d\u1eef li\u1ec7u, x\u00e1c nh\u1eadn ho\u1eb7c ho\u00e0n t\u00e1c thay \u0111\u1ed5i<\/span><\/td>\n<td style=\"padding: 10px; border: 1px solid #ccc;\"><span style=\"color: #000000;\">COMMIT, ROLLBACK, SAVEPOINT<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Ngo\u00e0i ra, trong SQL c\u00f2n c\u00f3 nhi\u1ec1u m\u1ec7nh \u0111\u1ec1 v\u00e0 c\u00e2u l\u1ec7nh ph\u1ee5 tr\u1ee3 quan tr\u1ecdng nh\u01b0 WHERE (l\u1ecdc \u0111i\u1ec1u ki\u1ec7n), JOIN (k\u1ebft h\u1ee3p b\u1ea3ng), DISTINCT (lo\u1ea1i b\u1ecf tr\u00f9ng l\u1eb7p), IN, BETWEEN, LIKE \u0111\u1ec3 h\u1ed7 tr\u1ee3 truy v\u1ea5n v\u00e0 x\u1eed l\u00fd d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch linh ho\u1ea1t h\u01a1n.<\/p>\n<p>T\u1ed5ng quan, c\u00e1c c\u00e2u l\u1ec7nh SQL \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng ph\u1ed1i h\u1ee3p \u0111\u1ec3 t\u1ea1o c\u1ea5u tr\u00fac, qu\u1ea3n l\u00fd quy\u1ec1n, thao t\u00e1c v\u00e0 truy v\u1ea5n d\u1eef li\u1ec7u trong h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u quan h\u1ec7 m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3.<\/p>\n<p>Vi\u1ec7c hi\u1ec3u r\u00f5 t\u1eebng lo\u1ea1i v\u00e0 c\u00e1ch s\u1eed d\u1ee5ng c\u00e2u l\u1ec7nh s\u1ebd gi\u00fap ng\u01b0\u1eddi d\u00f9ng v\u00e0 l\u1eadp tr\u00ecnh vi\u00ean thao t\u00e1c v\u00e0 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u chuy\u00ean nghi\u1ec7p h\u01a1n.<code><\/code><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Tieu-chuan-SQL-la-gi\"><\/span>Ti\u00eau chu\u1ea9n SQL l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Ti\u00eau chu\u1ea9n SQL \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp b\u1edfi <strong>ANSI<\/strong> (American National Standards Institute) v\u00e0 <strong>ISO<\/strong> (International Organization for Standardization).<\/p>\n<p>Ti\u00eau chu\u1ea9n n\u00e0y \u0111\u1ea3m b\u1ea3o r\u1eb1ng c\u00e1c c\u00e2u l\u1ec7nh SQL c\u01a1 b\u1ea3n (nh\u01b0 <code>SELECT<\/code>, <code>INSERT<\/code>, <code>UPDATE<\/code>, <code>DELETE<\/code>) c\u00f3 c\u00fa ph\u00e1p v\u00e0 h\u00e0nh vi nh\u1ea5t qu\u00e1n tr\u00ean h\u1ea7u h\u1ebft c\u00e1c h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u kh\u00e1c nhau gi\u00fap c\u00e1c l\u1eadp tr\u00ecnh vi\u00ean c\u00f3 th\u1ec3 chuy\u1ec3n \u0111\u1ed5i gi\u1eefa c\u00e1c h\u1ec7 th\u1ed1ng m\u00e0 kh\u00f4ng c\u1ea7n h\u1ecdc l\u1ea1i t\u1eeb \u0111\u1ea7u.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Hanh-dong-dua-SQL-vao-la-gi\"><\/span>H\u00e0nh \u0111\u1ed9ng \u0111\u01b0a SQL v\u00e0o l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>H\u00e0nh \u0111\u1ed9ng n\u00e0y \u0111\u01b0\u1ee3c bi\u1ebft \u0111\u1ebfn v\u1edbi t\u00ean g\u1ecdi <strong>SQL Injection<\/strong> (T\u1ea5n c\u00f4ng Ti\u00eam nhi\u1ec5m SQL). \u0110\u00e2y l\u00e0 m\u1ed9t trong nh\u1eefng k\u1ef9 thu\u1eadt t\u1ea5n c\u00f4ng <a href=\"https:\/\/interdata.vn\/blog\/web-application-la-gi\/\">\u1ee9ng d\u1ee5ng web<\/a> ph\u1ed5 bi\u1ebfn v\u00e0 nguy hi\u1ec3m nh\u1ea5t, li\u00ean t\u1ee5c xu\u1ea5t hi\u1ec7n trong danh s\u00e1ch <strong><a href=\"https:\/\/interdata.vn\/blog\/owasp-owasp-top-10-la-gi\/\">OWASP<\/a> Top 10<\/strong> v\u1ec1 r\u1ee7i ro b\u1ea3o m\u1eadt.<\/p>\n<p>K\u1ebb t\u1ea5n c\u00f4ng l\u1ee3i d\u1ee5ng l\u1ed7 h\u1ed5ng trong <a href=\"https:\/\/interdata.vn\/blog\/source-code-la-gi\/\">m\u00e3 ngu\u1ed3n<\/a> \u0111\u1ec3 ch\u00e8n c\u00e1c \u0111o\u1ea1n m\u00e3 SQL \u0111\u1ed9c h\u1ea1i v\u00e0o c\u00e1c truy v\u1ea5n, t\u1eeb \u0111\u00f3 c\u00f3 th\u1ec3 xem, s\u1eeda \u0111\u1ed5i ho\u1eb7c x\u00f3a d\u1eef li\u1ec7u nh\u1ea1y c\u1ea3m.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-04.jpg\" alt=\"SQL\" width=\"600\" height=\"300\" class=\"aligncenter size-full wp-image-30031\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-04.jpg 600w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-04-300x150.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-04-360x180.jpg 360w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"MySQL-la-gi\"><\/span>MySQL l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>MySQL l\u00e0 m\u1ed9t h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u quan h\u1ec7 m\u00e3 ngu\u1ed3n m\u1edf (open-source relational database management system &#8211; RDBMS). \u0110\u00e2y l\u00e0 m\u1ed9t trong nh\u1eefng DBMS ph\u1ed5 bi\u1ebfn nh\u1ea5t tr\u00ean th\u1ebf gi\u1edbi, \u0111\u1eb7c bi\u1ec7t l\u00e0 trong c\u00e1c \u1ee9ng d\u1ee5ng web, v\u00e0 l\u00e0 th\u00e0nh ph\u1ea7n c\u1ed1t l\u00f5i c\u1ee7a <a href=\"https:\/\/interdata.vn\/blog\/stack-la-gi\/\">ng\u0103n x\u1ebfp<\/a> c\u00f4ng ngh\u1ec7 LAMP (<a href=\"https:\/\/interdata.vn\/blog\/he-dieu-hanh-linux-la-gi\/\">Linux<\/a>, <a href=\"https:\/\/interdata.vn\/blog\/apache-la-gi\/\">Apache<\/a>, MySQL, <a href=\"https:\/\/interdata.vn\/blog\/php-la-gi\/\">PHP<\/a>).<\/p>\n<p><strong>SQL so v\u1edbi MySQL:<\/strong><\/p>\n<p>Vi\u1ec7c so s\u00e1nh SQL v\u00e0 MySQL c\u0169ng gi\u1ed1ng nh\u01b0 so s\u00e1nh &#8220;ng\u00f4n ng\u1eef&#8221; v\u00e0 &#8220;m\u1ed9t ng\u01b0\u1eddi n\u00f3i ng\u00f4n ng\u1eef \u0111\u00f3&#8221;.<\/p>\n<ul>\n<li><strong>SQL<\/strong> l\u00e0 ng\u00f4n ng\u1eef ti\u00eau chu\u1ea9n \u0111\u1ec3 b\u1ea1n vi\u1ebft c\u00e1c truy v\u1ea5n.<\/li>\n<li><strong>MySQL<\/strong> l\u00e0 m\u1ed9t ph\u1ea7n m\u1ec1m c\u1ee5 th\u1ec3 (m\u1ed9t DBMS) hi\u1ec3u v\u00e0 th\u1ef1c thi c\u00e1c c\u00e2u l\u1ec7nh \u0111\u01b0\u1ee3c vi\u1ebft b\u1eb1ng ng\u00f4n ng\u1eef SQL.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"NoSQL-la-gi\"><\/span>NoSQL l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>NoSQL (th\u01b0\u1eddng \u0111\u01b0\u1ee3c d\u1ecbch l\u00e0 &#8220;Not only SQL&#8221;) l\u00e0 m\u1ed9t thu\u1eadt ng\u1eef d\u00f9ng \u0111\u1ec3 ch\u1ec9 c\u00e1c h\u1ec7 c\u01a1 s\u1edf d\u1eef li\u1ec7u kh\u00f4ng tu\u00e2n theo m\u00f4 h\u00ecnh b\u1ea3ng quan h\u1ec7 truy\u1ec1n th\u1ed1ng.<\/p>\n<p>C\u00e1c c\u01a1 s\u1edf d\u1eef li\u1ec7u NoSQL cung c\u1ea5p c\u00e1c m\u00f4 h\u00ecnh l\u01b0u tr\u1eef linh ho\u1ea1t h\u01a1n, v\u00ed d\u1ee5 nh\u01b0 d\u1ea1ng t\u00e0i li\u1ec7u (document-based), c\u1eb7p kh\u00f3a-gi\u00e1 tr\u1ecb (key-value), c\u1ed9t r\u1ed9ng (wide-column), ho\u1eb7c \u0111\u1ed3 th\u1ecb (graph).<\/p>\n<p><strong>SQL so v\u1edbi NoSQL:<\/strong><\/p>\n<p>S\u1ef1 l\u1ef1a ch\u1ecdn gi\u1eefa SQL v\u00e0 NoSQL ph\u1ee5 thu\u1ed9c ho\u00e0n to\u00e0n v\u00e0o y\u00eau c\u1ea7u c\u1ee7a \u1ee9ng d\u1ee5ng.<\/p>\n<ul>\n<li><strong>C\u1ea5u tr\u00fac:<\/strong> C\u01a1 s\u1edf d\u1eef li\u1ec7u SQL y\u00eau c\u1ea7u m\u1ed9t l\u01b0\u1ee3c \u0111\u1ed3 (<a href=\"https:\/\/interdata.vn\/blog\/schema-la-gi\/\">schema<\/a>) c\u1ee9ng nh\u1eafc, d\u1eef li\u1ec7u ph\u1ea3i tu\u00e2n theo c\u1ea5u tr\u00fac b\u1ea3ng \u0111\u00e3 \u0111\u1ecbnh s\u1eb5n. NoSQL th\u00ec linh ho\u1ea1t, cho ph\u00e9p l\u01b0u tr\u1eef d\u1eef li\u1ec7u phi c\u1ea5u tr\u00fac ho\u1eb7c b\u00e1n c\u1ea5u tr\u00fac.<\/li>\n<li><strong>Kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng:<\/strong> SQL th\u01b0\u1eddng m\u1edf r\u1ed9ng theo chi\u1ec1u d\u1ecdc (scale-up) b\u1eb1ng c\u00e1ch t\u0103ng s\u1ee9c m\u1ea1nh cho m\u00e1y ch\u1ee7. NoSQL \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1ec3 m\u1edf r\u1ed9ng theo chi\u1ec1u ngang (scale-out) b\u1eb1ng c\u00e1ch th\u00eam nhi\u1ec1u m\u00e1y ch\u1ee7 h\u01a1n.<\/li>\n<li><strong>\u1ee8ng d\u1ee5ng:<\/strong> SQL ph\u00f9 h\u1ee3p cho c\u00e1c \u1ee9ng d\u1ee5ng y\u00eau c\u1ea7u t\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u cao nh\u01b0 h\u1ec7 th\u1ed1ng ng\u00e2n h\u00e0ng, giao d\u1ecbch. NoSQL ph\u00f9 h\u1ee3p cho c\u00e1c \u1ee9ng d\u1ee5ng c\u00f3 l\u01b0\u1ee3ng d\u1eef li\u1ec7u l\u1edbn v\u00e0 thay \u0111\u1ed5i nhanh nh\u01b0 m\u1ea1ng x\u00e3 h\u1ed9i, ph\u00e2n t\u00edch Big Data.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"May-chu-SQL-la-gi\"><\/span>M\u00e1y ch\u1ee7 SQL l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Thu\u1eadt ng\u1eef &#8220;M\u00e1y ch\u1ee7 SQL&#8221; (SQL Server) c\u00f3 th\u1ec3 g\u00e2y nh\u1ea7m l\u1eabn v\u00ec n\u00f3 mang hai \u00fd ngh\u0129a:<\/p>\n<ul>\n<li><strong>Ngh\u0129a chung:<\/strong> M\u1ed9t <a href=\"https:\/\/interdata.vn\/blog\/server-vat-ly-la-gi\/\">m\u00e1y ch\u1ee7 v\u1eadt l\u00fd<\/a> ho\u1eb7c <a href=\"https:\/\/interdata.vn\/blog\/virtual-machine-la-gi\/\">m\u00e1y \u1ea3o<\/a> \u0111\u01b0\u1ee3c c\u00e0i \u0111\u1eb7t v\u00e0 c\u1ea5u h\u00ecnh \u0111\u1ec3 ch\u1ea1y m\u1ed9t h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u SQL (nh\u01b0 MySQL, <a href=\"https:\/\/interdata.vn\/blog\/postgresql-la-gi\/\">PostgreSQL<\/a>).<\/li>\n<li><strong>T\u00ean ri\u00eang:<\/strong> <strong>Microsoft SQL Server<\/strong>, l\u00e0 m\u1ed9t s\u1ea3n ph\u1ea9m h\u1ec7 qu\u1ea3n tr\u1ecb c\u01a1 s\u1edf d\u1eef li\u1ec7u quan h\u1ec7 do Microsoft ph\u00e1t tri\u1ec3n.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"Ly-do-ban-nen-hoc-SQL\"><\/span>L\u00fd do b\u1ea1n n\u00ean h\u1ecdc SQL<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Trong th\u1ecb tr\u01b0\u1eddng lao \u0111\u1ed9ng hi\u1ec7n nay, SQL kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t k\u1ef9 n\u0103ng &#8220;c\u00f3 th\u00ec t\u1ed1t&#8221; m\u00e0 \u0111\u00e3 tr\u1edf th\u00e0nh m\u1ed9t y\u00eau c\u1ea7u c\u01a1 b\u1ea3n cho r\u1ea5t nhi\u1ec1u v\u1ecb tr\u00ed.<\/p>\n<p>Theo c\u00e1c b\u00e1o c\u00e1o t\u1eeb Glassdoor, c\u00e1c v\u1ecb tr\u00ed nh\u01b0 Data Analyst, Business Analyst, v\u00e0 Data Scientist c\u00f3 m\u1ee9c l\u01b0\u01a1ng h\u1ea5p d\u1eabn \u0111\u1ec1u y\u00eau c\u1ea7u th\u00e0nh th\u1ea1o SQL.<\/p>\n<p>H\u1ecdc SQL gi\u00fap b\u1ea1n t\u1ef1 ch\u1ee7 h\u01a1n trong c\u00f4ng vi\u1ec7c, n\u00e2ng cao gi\u00e1 tr\u1ecb b\u1ea3n th\u00e2n v\u00e0 m\u1edf ra c\u00e1nh c\u1eeda \u0111\u1ebfn v\u1edbi ng\u00e0nh khoa h\u1ecdc d\u1eef li\u1ec7u \u0111\u1ea7y ti\u1ec1m n\u0103ng.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-05.jpg\" alt=\"SQL\" width=\"600\" height=\"395\" class=\"aligncenter size-full wp-image-30032\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-05.jpg 600w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/05\/SQL-05-300x198.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Hoc-SQL-bat-dau-tu-dau\"><\/span>H\u1ecdc SQL b\u1eaft \u0111\u1ea7u t\u1eeb \u0111\u00e2u?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>B\u1eaft \u0111\u1ea7u h\u1ecdc SQL kh\u00f4ng h\u1ec1 ph\u1ee9c t\u1ea1p. B\u1ea1n c\u00f3 th\u1ec3 theo m\u1ed9t l\u1ed9 tr\u00ecnh \u0111\u01a1n gi\u1ea3n v\u00e0 hi\u1ec7u qu\u1ea3 nh\u01b0 sau:<\/p>\n<ul>\n<li><strong>N\u1eafm v\u1eefng l\u00fd thuy\u1ebft:<\/strong> Hi\u1ec3u r\u00f5 c\u00e1c kh\u00e1i ni\u1ec7m c\u1ed1t l\u00f5i nh\u01b0 c\u01a1 s\u1edf d\u1eef li\u1ec7u quan h\u1ec7, b\u1ea3ng, kh\u00f3a ch\u00ednh, kh\u00f3a ngo\u1ea1i. B\u00e0i vi\u1ebft n\u00e0y l\u00e0 m\u1ed9t \u0111i\u1ec3m kh\u1edfi \u0111\u1ea7u t\u1ed1t.<\/li>\n<li><strong>C\u00e0i \u0111\u1eb7t m\u00f4i tr\u01b0\u1eddng:<\/strong> Ch\u1ecdn v\u00e0 c\u00e0i \u0111\u1eb7t m\u1ed9t DBMS mi\u1ec5n ph\u00ed nh\u01b0 MySQL ho\u1eb7c PostgreSQL tr\u00ean m\u00e1y t\u00ednh c\u1ee7a b\u1ea1n. Vi\u1ec7c n\u00e0y gi\u00fap b\u1ea1n c\u00f3 m\u1ed9t &#8220;s\u00e2n ch\u01a1i&#8221; \u0111\u1ec3 th\u1ef1c h\u00e0nh.<\/li>\n<li><strong>Th\u1ef1c h\u00e0nh c\u00e1c l\u1ec7nh c\u01a1 b\u1ea3n:<\/strong> B\u1eaft \u0111\u1ea7u v\u1edbi c\u00e1c l\u1ec7nh DQL (<code>SELECT<\/code>, <code>FROM<\/code>, <code>WHERE<\/code>, <code>GROUP BY<\/code>, <code>ORDER BY<\/code>) v\u00ec \u0111\u00e2y l\u00e0 nh\u00f3m l\u1ec7nh b\u1ea1n s\u1ebd d\u00f9ng nhi\u1ec1u nh\u1ea5t. Sau \u0111\u00f3 chuy\u1ec3n sang c\u00e1c l\u1ec7nh DML v\u00e0 DDL.<\/li>\n<li><strong>L\u00e0m vi\u1ec7c v\u1edbi d\u1ef1 \u00e1n nh\u1ecf:<\/strong> T\u00ecm c\u00e1c b\u1ed9 d\u1eef li\u1ec7u c\u00f4ng khai (public datasets) v\u00e0 th\u1eed tr\u1ea3 l\u1eddi c\u00e1c c\u00e2u h\u1ecfi kinh doanh b\u1eb1ng c\u00e1ch vi\u1ebft truy v\u1ea5n SQL. \u0110\u00e2y l\u00e0 c\u00e1ch h\u1ecdc hi\u1ec7u qu\u1ea3 nh\u1ea5t.<\/li>\n<\/ul>\n<p>SQL kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t c\u00f4ng c\u1ee5 m\u00e0 c\u00f2n l\u00e0 chi\u1ebfc ch\u00eca kh\u00f3a m\u1edf c\u00e1nh c\u1eeda d\u1eef li\u1ec7u cho b\u1ea5t k\u1ef3 ai l\u00e0m vi\u1ec7c trong th\u1eddi \u0111\u1ea1i s\u1ed1. D\u00f9 b\u1ea1n l\u00e0 l\u1eadp tr\u00ecnh vi\u00ean, nh\u00e0 ph\u00e2n t\u00edch d\u1eef li\u1ec7u, marketer hay qu\u1ea3n l\u00fd doanh nghi\u1ec7p, vi\u1ec7c hi\u1ec3u r\u00f5 SQL l\u00e0 g\u00ec v\u00e0 bi\u1ebft c\u00e1ch s\u1eed d\u1ee5ng ng\u00f4n ng\u1eef SQL s\u1ebd gi\u00fap b\u1ea1n khai th\u00e1c tri\u1ec7t \u0111\u1ec3 s\u1ee9c m\u1ea1nh c\u1ee7a d\u1eef li\u1ec7u, t\u1eeb \u0111\u00f3 \u0111\u01b0a ra quy\u1ebft \u0111\u1ecbnh ch\u00ednh x\u00e1c v\u00e0 k\u1ecbp th\u1eddi.<\/p>\n<p>B\u1eaft \u0111\u1ea7u h\u1ecdc SQL h\u00f4m nay ch\u00ednh l\u00e0 \u0111\u1ea7u t\u01b0 v\u00e0o n\u0103ng l\u1ef1c ngh\u1ec1 nghi\u1ec7p c\u1ee7a b\u1ea1n trong t\u01b0\u01a1ng lai, v\u1edbi m\u1ed9t l\u1ed9 tr\u00ecnh h\u1ecdc SQL r\u00f5 r\u00e0ng, m\u00f4i tr\u01b0\u1eddng th\u1ef1c h\u00e0nh ph\u00f9 h\u1ee3p, v\u00e0 s\u1ef1 ki\u00ean tr\u00ec, b\u1ea1n ho\u00e0n to\u00e0n c\u00f3 th\u1ec3 l\u00e0m ch\u1ee7 c\u00f4ng c\u1ee5 quan tr\u1ecdng n\u00e0y v\u00e0 ti\u1ebfn s\u00e2u h\u01a1n v\u00e0o th\u1ebf gi\u1edbi d\u1eef li\u1ec7u \u0111\u1ea7y ti\u1ec1m n\u0103ng.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Trong b\u1ed1i c\u1ea3nh m\u1ecdi quy\u1ebft \u0111\u1ecbnh kinh doanh \u0111\u1ec1u d\u1ef1a v\u00e0o d\u1eef li\u1ec7u, vi\u1ec7c hi\u1ec3u v\u00e0 s\u1eed d\u1ee5ng SQL kh\u00f4ng c\u00f2n l\u00e0 l\u1ef1a ch\u1ecdn m\u00e0 l\u00e0 m\u1ed9t y\u00eau c\u1ea7u t\u1ea5t y\u1ebfu. SQL ch\u00ednh l\u00e0 c\u00f4ng c\u1ee5 gi\u00fap khai th\u00e1c th\u00f4ng tin t\u1eeb d\u1eef li\u1ec7u th\u00f4. C\u00f9ng InterData t\u00ecm hi\u1ec3u ng\u00f4n ng\u1eef SQL l\u00e0 g\u00ec, c\u00e1ch<\/p>\n","protected":false},"author":11,"featured_media":30033,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[140],"tags":[],"class_list":["post-28398","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-lap-trinh"],"_links":{"self":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/28398","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/users\/11"}],"replies":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/comments?post=28398"}],"version-history":[{"count":13,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/28398\/revisions"}],"predecessor-version":[{"id":32090,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/28398\/revisions\/32090"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media\/30033"}],"wp:attachment":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media?parent=28398"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/categories?post=28398"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/tags?post=28398"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}