{"id":142083,"date":"2024-10-31T22:21:18","date_gmt":"2024-10-31T14:21:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/142083\/"},"modified":"2024-10-31T22:21:18","modified_gmt":"2024-10-31T14:21:18","slug":"sql%ef%bc%8c%e5%be%9e%e5%85%a5%e9%96%80%e5%88%b0%e7%86%9f%e7%b7%b4","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/142083\/","title":{"rendered":"SQL\uff0c\u5f9e\u5165\u9580\u5230\u719f\u7df4"},"content":{"rendered":"<h1 id=\"sql%ef%bc%8c%e5%be%9e%e5%85%a5%e9%96%80%e5%88%b0%e7%86%9f%e7%b7%b4-VrmmkUqXHG\">SQL\uff0c\u5f9e\u5165\u9580\u5230\u719f\u7df4<\/h1>\n<p>SQL\uff08\u7d50\u69cb\u5316\u67e5\u8a62\u8a9e\u8a00\uff09\u662f\u4e00\u7a2e\u5c08\u9580\u7528\u65bc\u7ba1\u7406\u548c\u64cd\u4f5c\u95dc\u4fc2\u578b\u6578\u64da\u5eab\u7684\u8a9e\u8a00\u3002\u7121\u8ad6\u662f\u958b\u767c\u8005\u3001\u6578\u64da\u5206\u6790\u5e2b\u9084\u662f\u6578\u64da\u5eab\u7ba1\u7406\u54e1\uff0c\u638c\u63e1SQL\u90fd\u662f\u4e00\u9805\u57fa\u672c\u6280\u80fd\u3002\u672c\u6587\u5c07\u5e36\u60a8\u5f9eSQL\u7684\u57fa\u672c\u6982\u5ff5\u958b\u59cb\uff0c\u9010\u6b65\u6df1\u5165\u5230\u66f4\u9ad8\u7d1a\u7684\u61c9\u7528\uff0c\u5e6b\u52a9\u60a8\u5f9e\u5165\u9580\u5230\u719f\u7df4\u3002<\/p>\n<h2 id=\"sql%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-VrmmkUqXHG\">SQL\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>SQL\u7684\u4e3b\u8981\u529f\u80fd\u662f\u7528\u4f86\u67e5\u8a62\u3001\u63d2\u5165\u3001\u66f4\u65b0\u548c\u522a\u9664\u6578\u64da\u3002\u5b83\u7684\u8a9e\u6cd5\u7c21\u55ae\u660e\u77ad\uff0c\u6613\u65bc\u5b78\u7fd2\u3002SQL\u7684\u57fa\u672c\u7d44\u6210\u90e8\u5206\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><strong>\u6578\u64da\u5b9a\u7fa9\u8a9e\u8a00\uff08DDL\uff09<\/strong>\uff1a\u7528\u65bc\u5b9a\u7fa9\u6578\u64da\u5eab\u7d50\u69cb\u7684\u8a9e\u8a00\uff0c\u5982\u5275\u5efa\u3001\u4fee\u6539\u548c\u522a\u9664\u8868\u683c\u3002<\/li>\n<li><strong>\u6578\u64da\u64cd\u4f5c\u8a9e\u8a00\uff08DML\uff09<\/strong>\uff1a\u7528\u65bc\u64cd\u4f5c\u6578\u64da\u7684\u8a9e\u8a00\uff0c\u5982\u63d2\u5165\u3001\u66f4\u65b0\u548c\u522a\u9664\u6578\u64da\u3002<\/li>\n<li><strong>\u6578\u64da\u67e5\u8a62\u8a9e\u8a00\uff08DQL\uff09<\/strong>\uff1a\u7528\u65bc\u67e5\u8a62\u6578\u64da\u7684\u8a9e\u8a00\uff0c\u4e3b\u8981\u662fSELECT\u8a9e\u53e5\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%9f%ba%e6%9c%acsql%e8%aa%9e%e5%8f%a5-VrmmkUqXHG\">\u57fa\u672cSQL\u8a9e\u53e5<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e9b\u57fa\u672c\u7684SQL\u8a9e\u53e5\u793a\u4f8b\uff1a<\/p>\n<h3 id=\"%e5%89%b5%e5%bb%ba%e8%a1%a8%e6%a0%bc-VrmmkUqXHG\">\u5275\u5efa\u8868\u683c<\/h3>\n<pre><code>CREATE TABLE users (\n    id INT PRIMARY KEY AUTO_INCREMENT,\n    name VARCHAR(100),\n    email VARCHAR(100)\n);<\/code><\/pre>\n<h3 id=\"%e6%8f%92%e5%85%a5%e6%95%b8%e6%93%9a-VrmmkUqXHG\">\u63d2\u5165\u6578\u64da<\/h3>\n<pre><code>INSERT INTO users (name, email) VALUES ('\u5f35\u4e09', 'zhangsan@example.com');<\/code><\/pre>\n<h3 id=\"%e6%9f%a5%e8%a9%a2%e6%95%b8%e6%93%9a-VrmmkUqXHG\">\u67e5\u8a62\u6578\u64da<\/h3>\n<pre><code>SELECT * FROM users;<\/code><\/pre>\n<h3 id=\"%e6%9b%b4%e6%96%b0%e6%95%b8%e6%93%9a-VrmmkUqXHG\">\u66f4\u65b0\u6578\u64da<\/h3>\n<pre><code>UPDATE users SET email = 'zhangsan_new@example.com' WHERE name = '\u5f35\u4e09';<\/code><\/pre>\n<h3 id=\"%e5%88%aa%e9%99%a4%e6%95%b8%e6%93%9a-VrmmkUqXHG\">\u522a\u9664\u6578\u64da<\/h3>\n<pre><code>DELETE FROM users WHERE name = '\u5f35\u4e09';<\/code><\/pre>\n<h2 id=\"%e9%80%b2%e9%9a%8esql%e6%8a%80%e5%b7%a7-VrmmkUqXHG\">\u9032\u968eSQL\u6280\u5de7<\/h2>\n<p>\u5728\u638c\u63e1\u4e86\u57fa\u672c\u7684SQL\u8a9e\u53e5\u5f8c\uff0c\u60a8\u53ef\u4ee5\u9032\u4e00\u6b65\u5b78\u7fd2\u4e00\u4e9b\u9032\u968e\u6280\u5de7\uff0c\u4ee5\u63d0\u9ad8\u60a8\u7684\u6578\u64da\u64cd\u4f5c\u80fd\u529b\u3002<\/p>\n<h3 id=\"%e4%bd%bf%e7%94%a8join%e8%aa%9e%e5%8f%a5-VrmmkUqXHG\">\u4f7f\u7528JOIN\u8a9e\u53e5<\/h3>\n<p>JOIN\u8a9e\u53e5\u7528\u65bc\u5f9e\u591a\u500b\u8868\u4e2d\u67e5\u8a62\u6578\u64da\u3002\u4ee5\u4e0b\u662fINNER JOIN\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT users.name, orders.amount\nFROM users\nINNER JOIN orders ON users.id = orders.user_id;<\/code><\/pre>\n<h3 id=\"%e4%bd%bf%e7%94%a8%e8%81%9a%e5%90%88%e5%87%bd%e6%95%b8-VrmmkUqXHG\">\u4f7f\u7528\u805a\u5408\u51fd\u6578<\/h3>\n<p>\u805a\u5408\u51fd\u6578\u5982COUNT\u3001SUM\u3001AVG\u7b49\u53ef\u4ee5\u5e6b\u52a9\u60a8\u9032\u884c\u6578\u64da\u5206\u6790\uff1a<\/p>\n<pre><code>SELECT COUNT(*) FROM users;<\/code><\/pre>\n<h3 id=\"%e4%bd%bf%e7%94%a8%e5%ad%90%e6%9f%a5%e8%a9%a2-VrmmkUqXHG\">\u4f7f\u7528\u5b50\u67e5\u8a62<\/h3>\n<p>\u5b50\u67e5\u8a62\u53ef\u4ee5\u5728\u4e00\u500b\u67e5\u8a62\u4e2d\u5d4c\u5957\u53e6\u4e00\u500b\u67e5\u8a62\uff0c\u9019\u5c0d\u65bc\u8907\u96dc\u7684\u6578\u64da\u6aa2\u7d22\u975e\u5e38\u6709\u7528\uff1a<\/p>\n<pre><code>SELECT name FROM users WHERE id IN (SELECT user_id FROM orders WHERE amount &gt; 100);<\/code><\/pre>\n<h2 id=\"%e5%ad%b8%e7%bf%92%e8%b3%87%e6%ba%90-VrmmkUqXHG\">\u5b78\u7fd2\u8cc7\u6e90<\/h2>\n<p>\u8981\u5f9e\u5165\u9580\u5230\u719f\u7df4\uff0c\u6301\u7e8c\u5b78\u7fd2\u662f\u5fc5\u4e0d\u53ef\u5c11\u7684\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u63a8\u85a6\u7684\u5b78\u7fd2\u8cc7\u6e90\uff1a<\/p>\n<ul>\n<li><a href=\"https:\/\/www.w3schools.com\/sql\/\" rel=\"nofollow noopener\" target=\"_blank\">W3Schools SQL Tutorial<\/a><\/li>\n<li><a href=\"https:\/\/www.codecademy.com\/learn\/learn-sql\" rel=\"nofollow noopener\" target=\"_blank\">Codecademy SQL Course<\/a><\/li>\n<li><a href=\"https:\/\/www.sqlzoo.net\/\" rel=\"nofollow noopener\" target=\"_blank\">SQLZoo<\/a><\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-VrmmkUqXHG\">\u7e3d\u7d50<\/h2>\n<p>SQL\u662f\u4e00\u9580\u5f37\u5927\u7684\u8a9e\u8a00\uff0c\u80fd\u5920\u5e6b\u52a9\u60a8\u6709\u6548\u5730\u7ba1\u7406\u548c\u64cd\u4f5c\u6578\u64da\u3002\u5f9e\u57fa\u672c\u7684\u6578\u64da\u64cd\u4f5c\u5230\u9032\u968e\u7684\u67e5\u8a62\u6280\u5de7\uff0c\u638c\u63e1SQL\u5c07\u4f7f\u60a8\u5728\u6578\u64da\u8655\u7406\u548c\u5206\u6790\u65b9\u9762\u5177\u5099\u7af6\u722d\u512a\u52e2\u3002\u5982\u679c\u60a8\u9700\u8981\u7a69\u5b9a\u7684\u6578\u64da\u5eab\u652f\u6301\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u6216<a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a>\u4f86\u642d\u5efa\u60a8\u7684\u6578\u64da\u74b0\u5883\uff0c\u9019\u5c07\u70ba\u60a8\u7684\u5b78\u7fd2\u548c\u5be6\u8e10\u63d0\u4f9b\u826f\u597d\u7684\u57fa\u790e\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u638c\u63e1SQL\u5f9e\u5165\u9580\u5230\u719f\u7df4\uff0c\u5b78\u7fd2\u6578\u64da\u5eab\u67e5\u8a62\u3001\u7ba1\u7406\u548c\u5206\u6790\u6280\u5de7\uff0c\u63d0\u5347\u4f60\u7684\u6578\u64da\u8655\u7406\u80fd\u529b\uff0c\u958b\u555f\u8077\u696d\u65b0\u6a5f\u6703\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-142083","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/142083","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=142083"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/142083\/revisions"}],"predecessor-version":[{"id":142084,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/142083\/revisions\/142084"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=142083"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=142083"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=142083"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}