{"id":188120,"date":"2024-11-11T19:57:23","date_gmt":"2024-11-11T11:57:23","guid":{"rendered":"https:\/\/server.hk\/cnblog\/188120\/"},"modified":"2024-11-11T19:57:24","modified_gmt":"2024-11-11T11:57:24","slug":"%e8%aa%aa%e8%aa%aa%e4%b8%80%e4%ba%9b%e6%9c%89%e7%94%a8%e7%9a%84mysql%e8%aa%9e%e5%8f%a5","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/188120\/","title":{"rendered":"\u8aaa\u8aaa\u4e00\u4e9b\u6709\u7528\u7684MySQL\u8a9e\u53e5"},"content":{"rendered":"<h1 id=\"%e8%aa%aa%e8%aa%aa%e4%b8%80%e4%ba%9b%e6%9c%89%e7%94%a8%e7%9a%84mysql%e8%aa%9e%e5%8f%a5-mJmTzfrAwh\">\u8aaa\u8aaa\u4e00\u4e9b\u6709\u7528\u7684MySQL\u8a9e\u53e5<\/h1>\n<p>MySQL\u662f\u4e00\u7a2e\u6d41\u884c\u7684\u958b\u6e90\u95dc\u806f\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\uff0c\u5ee3\u6cdb\u61c9\u7528\u65bc\u5404\u7a2e\u7db2\u7ad9\u548c\u61c9\u7528\u7a0b\u5e8f\u4e2d\u3002\u7121\u8ad6\u662f\u958b\u767c\u8005\u9084\u662f\u6578\u64da\u5206\u6790\u5e2b\uff0c\u638c\u63e1\u4e00\u4e9b\u57fa\u672c\u7684MySQL\u8a9e\u53e5\u90fd\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u4e00\u4e9b\u6709\u7528\u7684MySQL\u8a9e\u53e5\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u6709\u6548\u5730\u7ba1\u7406\u548c\u67e5\u8a62\u6578\u64da\u3002<\/p>\n<h2 id=\"1-%e5%9f%ba%e6%9c%ac%e6%9f%a5%e8%a9%a2%e8%aa%9e%e5%8f%a5-mJmTzfrAwh\">1. \u57fa\u672c\u67e5\u8a62\u8a9e\u53e5<\/h2>\n<p>\u6700\u57fa\u672c\u7684\u67e5\u8a62\u8a9e\u53e5\u662fSELECT\u8a9e\u53e5\uff0c\u7528\u65bc\u5f9e\u6578\u64da\u5eab\u4e2d\u6aa2\u7d22\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u57fa\u672c\u7684\u4f7f\u7528\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>SELECT * FROM users;<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u5f9e\u540d\u70bausers\u7684\u8868\u4e2d\u9078\u64c7\u6240\u6709\u5217\u7684\u6240\u6709\u884c\u3002\u5982\u679c\u53ea\u60f3\u9078\u64c7\u7279\u5b9a\u7684\u5217\uff0c\u53ef\u4ee5\u9019\u6a23\u5beb\uff1a<\/p>\n<pre><code>SELECT username, email FROM users;<\/code><\/pre>\n<h2 id=\"2-%e6%a2%9d%e4%bb%b6%e6%9f%a5%e8%a9%a2-mJmTzfrAwh\">2. \u689d\u4ef6\u67e5\u8a62<\/h2>\n<p>\u5728\u67e5\u8a62\u6578\u64da\u6642\uff0c\u7d93\u5e38\u9700\u8981\u6839\u64da\u7279\u5b9a\u689d\u4ef6\u904e\u6ffe\u7d50\u679c\u3002\u53ef\u4ee5\u4f7f\u7528WHERE\u5b50\u53e5\u4f86\u5be6\u73fe\uff1a<\/p>\n<pre><code>SELECT * FROM users WHERE age &gt; 18;<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u5e74\u9f61\u5927\u65bc18\u7684\u7528\u6236\u3002<\/p>\n<h2 id=\"3-%e6%8e%92%e5%ba%8f%e7%b5%90%e6%9e%9c-mJmTzfrAwh\">3. \u6392\u5e8f\u7d50\u679c<\/h2>\n<p>\u4f7f\u7528ORDER BY\u5b50\u53e5\u53ef\u4ee5\u5c0d\u67e5\u8a62\u7d50\u679c\u9032\u884c\u6392\u5e8f\u3002\u4ee5\u4e0b\u662f\u6309\u5e74\u9f61\u5347\u5e8f\u6392\u5217\u7684\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>SELECT * FROM users ORDER BY age ASC;<\/code><\/pre>\n<p>\u5982\u679c\u60f3\u8981\u6309\u5e74\u9f61\u964d\u5e8f\u6392\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528DESC\uff1a<\/p>\n<pre><code>SELECT * FROM users ORDER BY age DESC;<\/code><\/pre>\n<h2 id=\"4-%e8%81%9a%e5%90%88%e5%87%bd%e6%95%b8-mJmTzfrAwh\">4. \u805a\u5408\u51fd\u6578<\/h2>\n<p>MySQL\u63d0\u4f9b\u4e86\u591a\u7a2e\u805a\u5408\u51fd\u6578\uff0c\u5982COUNT\u3001SUM\u3001AVG\u7b49\uff0c\u7528\u65bc\u8a08\u7b97\u6578\u64da\u7684\u7d71\u8a08\u4fe1\u606f\u3002\u4f8b\u5982\uff0c\u8a08\u7b97\u7528\u6236\u7684\u7e3d\u6578\uff1a<\/p>\n<pre><code>SELECT COUNT(*) FROM users;<\/code><\/pre>\n<p>\u8a08\u7b97\u7528\u6236\u5e74\u9f61\u7684\u5e73\u5747\u503c\uff1a<\/p>\n<pre><code>SELECT AVG(age) FROM users;<\/code><\/pre>\n<h2 id=\"5-%e5%88%86%e7%b5%84%e6%9f%a5%e8%a9%a2-mJmTzfrAwh\">5. \u5206\u7d44\u67e5\u8a62<\/h2>\n<p>\u4f7f\u7528GROUP BY\u5b50\u53e5\u53ef\u4ee5\u5c07\u67e5\u8a62\u7d50\u679c\u6309\u67d0\u4e00\u5217\u5206\u7d44\uff0c\u4e26\u7d50\u5408\u805a\u5408\u51fd\u6578\u9032\u884c\u7d71\u8a08\u3002\u4f8b\u5982\uff0c\u6309\u6027\u5225\u5206\u7d44\u4e26\u8a08\u7b97\u6bcf\u500b\u6027\u5225\u7684\u7528\u6236\u6578\uff1a<\/p>\n<pre><code>SELECT gender, COUNT(*) FROM users GROUP BY gender;<\/code><\/pre>\n<h2 id=\"6-%e6%8f%92%e5%85%a5%e6%95%b8%e6%93%9a-mJmTzfrAwh\">6. \u63d2\u5165\u6578\u64da<\/h2>\n<p>\u8981\u5411\u8868\u4e2d\u63d2\u5165\u6578\u64da\uff0c\u53ef\u4ee5\u4f7f\u7528INSERT INTO\u8a9e\u53e5\u3002\u4ee5\u4e0b\u662f\u63d2\u5165\u4e00\u689d\u65b0\u7528\u6236\u7684\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>INSERT INTO users (username, email, age) VALUES ('john_doe', 'john@example.com', 25);<\/code><\/pre>\n<h2 id=\"7-%e6%9b%b4%e6%96%b0%e6%95%b8%e6%93%9a-mJmTzfrAwh\">7. \u66f4\u65b0\u6578\u64da<\/h2>\n<p>\u4f7f\u7528UPDATE\u8a9e\u53e5\u53ef\u4ee5\u66f4\u65b0\u8868\u4e2d\u7684\u6578\u64da\u3002\u4f8b\u5982\uff0c\u5c07\u7528\u6236\u7684\u5e74\u9f61\u66f4\u65b0\u70ba30\uff1a<\/p>\n<pre><code>UPDATE users SET age = 30 WHERE username = 'john_doe';<\/code><\/pre>\n<h2 id=\"8-%e5%88%aa%e9%99%a4%e6%95%b8%e6%93%9a-mJmTzfrAwh\">8. \u522a\u9664\u6578\u64da<\/h2>\n<p>\u8981\u522a\u9664\u8868\u4e2d\u7684\u6578\u64da\uff0c\u53ef\u4ee5\u4f7f\u7528DELETE\u8a9e\u53e5\u3002\u4ee5\u4e0b\u662f\u522a\u9664\u7279\u5b9a\u7528\u6236\u7684\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>DELETE FROM users WHERE username = 'john_doe';<\/code><\/pre>\n<h2 id=\"9-%e5%89%b5%e5%bb%ba%e8%a1%a8-mJmTzfrAwh\">9. \u5275\u5efa\u8868<\/h2>\n<p>\u5728MySQL\u4e2d\u5275\u5efa\u65b0\u8868\u53ef\u4ee5\u4f7f\u7528CREATE TABLE\u8a9e\u53e5\u3002\u4ee5\u4e0b\u662f\u5275\u5efa\u4e00\u500b\u7528\u6236\u8868\u7684\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>CREATE TABLE users (\n    id INT AUTO_INCREMENT PRIMARY KEY,\n    username VARCHAR(50) NOT NULL,\n    email VARCHAR(100) NOT NULL,\n    age INT\n);<\/code><\/pre>\n<h2 id=\"10-%e6%95%b8%e6%93%9a%e5%ba%ab%e7%9a%84%e5%82%99%e4%bb%bd%e8%88%87%e6%81%a2%e5%be%a9-mJmTzfrAwh\">10. \u6578\u64da\u5eab\u7684\u5099\u4efd\u8207\u6062\u5fa9<\/h2>\n<p>\u5099\u4efd\u6578\u64da\u5eab\u662f\u78ba\u4fdd\u6578\u64da\u5b89\u5168\u7684\u91cd\u8981\u6b65\u9a5f\u3002\u53ef\u4ee5\u4f7f\u7528mysqldump\u547d\u4ee4\u4f86\u5099\u4efd\u6578\u64da\u5eab\uff1a<\/p>\n<pre><code>mysqldump -u username -p database_name &gt; backup.sql<\/code><\/pre>\n<p>\u8981\u6062\u5fa9\u6578\u64da\u5eab\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n<pre><code>mysql -u username -p database_name &lt; backup.sql<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-mJmTzfrAwh\">\u7e3d\u7d50<\/h2>\n<p>\u638c\u63e1\u9019\u4e9b\u57fa\u672c\u7684MySQL\u8a9e\u53e5\u5c07\u6709\u52a9\u65bc\u60a8\u66f4\u6709\u6548\u5730\u7ba1\u7406\u548c\u67e5\u8a62\u6578\u64da\u3002\u7121\u8ad6\u60a8\u662f\u958b\u767c\u8005\u9084\u662f\u6578\u64da\u5206\u6790\u5e2b\uff0c\u9019\u4e9b\u8a9e\u53e5\u90fd\u662f\u65e5\u5e38\u5de5\u4f5c\u4e2d\u4e0d\u53ef\u6216\u7f3a\u7684\u5de5\u5177\u3002\u5982\u679c\u60a8\u9700\u8981\u66f4\u9ad8\u6548\u7684\u6578\u64da\u7ba1\u7406\u89e3\u6c7a\u65b9\u6848\uff0c\u53ef\u4ee5\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u6216<a href=\"https:\/\/server.hk\">\u4e91\u670d\u52a1\u5668<\/a>\u4f86\u652f\u6301\u60a8\u7684\u61c9\u7528\u7a0b\u5e8f\u548c\u7db2\u7ad9\u3002\u4e86\u89e3\u66f4\u591a\u4fe1\u606f\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22\u4e00\u4e9b\u6709\u7528\u7684MySQL\u8a9e\u53e5\uff0c\u63d0\u5347\u6578\u64da\u5eab\u7ba1\u7406\u6548\u7387\uff0c\u7c21\u5316\u67e5\u8a62\u548c\u64cd\u4f5c\uff0c\u52a9\u4f60\u8f15\u9b06\u8655\u7406\u6578\u64da\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-188120","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/188120","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=188120"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/188120\/revisions"}],"predecessor-version":[{"id":188121,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/188120\/revisions\/188121"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=188120"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=188120"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=188120"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}