{"id":76036,"date":"2024-10-16T03:19:20","date_gmt":"2024-10-15T19:19:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/76036\/"},"modified":"2024-10-16T03:19:20","modified_gmt":"2024-10-15T19:19:20","slug":"mysql-%e5%bb%ba%e7%ab%8b%e7%b4%a2%e5%bc%95%e7%9a%84%e6%99%82%e6%a9%9f%e6%8f%8f%e8%bf%b0","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/76036\/","title":{"rendered":"MySQL \u5efa\u7acb\u7d22\u5f15\u7684\u6642\u6a5f\u63cf\u8ff0"},"content":{"rendered":"<h1 id=\"mysql-%e5%bb%ba%e7%ab%8b%e7%b4%a2%e5%bc%95%e7%9a%84%e6%99%82%e6%a9%9f%e6%8f%8f%e8%bf%b0-gelmhiBHUl\">MySQL \u5efa\u7acb\u7d22\u5f15\u7684\u6642\u6a5f\u63cf\u8ff0<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0c\u7d22\u5f15\u662f\u4e00\u7a2e\u91cd\u8981\u7684\u8cc7\u6599\u7d50\u69cb\uff0c\u80fd\u5920\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\u3002MySQL \u4f5c\u70ba\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u958b\u6e90\u8cc7\u6599\u5eab\uff0c\u63d0\u4f9b\u4e86\u591a\u7a2e\u7d22\u5f15\u985e\u578b\u548c\u5efa\u7acb\u7d22\u5f15\u7684\u65b9\u5f0f\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5728 MySQL \u4e2d\u5efa\u7acb\u7d22\u5f15\u7684\u6700\u4f73\u6642\u6a5f\uff0c\u4ee5\u53ca\u5982\u4f55\u6709\u6548\u5730\u4f7f\u7528\u7d22\u5f15\u4f86\u512a\u5316\u8cc7\u6599\u5eab\u6027\u80fd\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e7%b4%a2%e5%bc%95%ef%bc%9f-gelmhiBHUl\">\u4ec0\u9ebc\u662f\u7d22\u5f15\uff1f<\/h2>\n<p>\u7d22\u5f15\u662f\u4e00\u7a2e\u8cc7\u6599\u7d50\u69cb\uff0c\u80fd\u5920\u52a0\u901f\u8cc7\u6599\u6aa2\u7d22\u7684\u904e\u7a0b\u3002\u5b83\u985e\u4f3c\u65bc\u66f8\u7c4d\u7684\u76ee\u9304\uff0c\u5e6b\u52a9\u8cc7\u6599\u5eab\u5feb\u901f\u5b9a\u4f4d\u5230\u6240\u9700\u7684\u8cc7\u6599\u3002MySQL \u652f\u63f4\u591a\u7a2e\u7d22\u5f15\u985e\u578b\uff0c\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><strong>B-Tree \u7d22\u5f15\uff1a<\/strong>\u6700\u5e38\u7528\u7684\u7d22\u5f15\u985e\u578b\uff0c\u9069\u7528\u65bc\u7bc4\u570d\u67e5\u8a62\u3002<\/li>\n<li><strong>\u54c8\u5e0c\u7d22\u5f15\uff1a<\/strong>\u9069\u5408\u7cbe\u78ba\u67e5\u8a62\uff0c\u4f46\u4e0d\u652f\u63f4\u7bc4\u570d\u67e5\u8a62\u3002<\/li>\n<li><strong>\u5168\u6587\u7d22\u5f15\uff1a<\/strong>\u7528\u65bc\u5feb\u901f\u67e5\u8a62\u6587\u672c\u8cc7\u6599\u3002<\/li>\n<li><strong>\u7a7a\u9593\u7d22\u5f15\uff1a<\/strong>\u5c08\u70ba\u5730\u7406\u8cc7\u6599\u8a2d\u8a08\u3002<\/li>\n<\/ul>\n<h2 id=\"%e4%bd%95%e6%99%82%e6%87%89%e8%a9%b2%e5%bb%ba%e7%ab%8b%e7%b4%a2%e5%bc%95%ef%bc%9f-gelmhiBHUl\">\u4f55\u6642\u61c9\u8a72\u5efa\u7acb\u7d22\u5f15\uff1f<\/h2>\n<p>\u5efa\u7acb\u7d22\u5f15\u7684\u6642\u6a5f\u53d6\u6c7a\u65bc\u591a\u7a2e\u56e0\u7d20\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u60c5\u6cc1\uff1a<\/p>\n<h3 id=\"1-%e6%9f%a5%e8%a9%a2%e9%a0%bb%e7%b9%81%e7%9a%84%e6%ac%84%e4%bd%8d-gelmhiBHUl\">1. \u67e5\u8a62\u983b\u7e41\u7684\u6b04\u4f4d<\/h3>\n<p>\u5982\u679c\u67d0\u500b\u6b04\u4f4d\u7d93\u5e38\u51fa\u73fe\u5728\u67e5\u8a62\u689d\u4ef6\u4e2d\uff0c\u5247\u61c9\u8003\u616e\u70ba\u8a72\u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\u3002\u4f8b\u5982\uff0c\u5047\u8a2d\u6709\u4e00\u500b\u7528\u6236\u8cc7\u6599\u8868\uff0c\u7d93\u5e38\u6839\u64da\u7528\u6236\u540d\u67e5\u8a62\u7528\u6236\u8cc7\u6599\uff1a<\/p>\n<pre><code>SELECT * FROM users WHERE username = 'example_user';<\/code><\/pre>\n<p>\u5728\u9019\u7a2e\u60c5\u6cc1\u4e0b\uff0c\u70ba <code>username<\/code> \u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u901f\u5ea6\u3002<\/p>\n<h3 id=\"2-%e5%a4%a7%e5%9e%8b%e8%b3%87%e6%96%99%e8%a1%a8-gelmhiBHUl\">2. \u5927\u578b\u8cc7\u6599\u8868<\/h3>\n<p>\u5c0d\u65bc\u5927\u578b\u8cc7\u6599\u8868\uff0c\u67e5\u8a62\u6027\u80fd\u53ef\u80fd\u6703\u53d7\u5230\u5f71\u97ff\u3002\u5efa\u7acb\u7d22\u5f15\u53ef\u4ee5\u5e6b\u52a9\u6e1b\u5c11\u8cc7\u6599\u6383\u63cf\u7684\u7bc4\u570d\u3002\u4f8b\u5982\uff0c\u5c0d\u65bc\u4e00\u500b\u5305\u542b\u6578\u767e\u842c\u689d\u8a18\u9304\u7684\u4ea4\u6613\u8cc7\u6599\u8868\uff0c\u5c0d <code>transaction_date<\/code> \u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\u53ef\u4ee5\u52a0\u901f\u57fa\u65bc\u65e5\u671f\u7684\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT * FROM transactions WHERE transaction_date BETWEEN '2023-01-01' AND '2023-01-31';<\/code><\/pre>\n<h3 id=\"3-%e9%80%a3%e6%8e%a5%e6%9f%a5%e8%a9%a2-gelmhiBHUl\">3. \u9023\u63a5\u67e5\u8a62<\/h3>\n<p>\u5728\u9032\u884c\u591a\u8868\u9023\u63a5\u67e5\u8a62\u6642\uff0c\u70ba\u9023\u63a5\u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT * FROM orders o JOIN customers c ON o.customer_id = c.id;<\/code><\/pre>\n<p>\u5728\u9019\u7a2e\u60c5\u6cc1\u4e0b\uff0c\u70ba <code>customer_id<\/code> \u548c <code>id<\/code> \u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\u53ef\u4ee5\u52a0\u901f\u67e5\u8a62\u3002<\/p>\n<h3 id=\"4-%e6%8e%92%e5%ba%8f%e5%92%8c%e5%88%86%e7%b5%84-gelmhiBHUl\">4. \u6392\u5e8f\u548c\u5206\u7d44<\/h3>\n<p>\u5982\u679c\u67e5\u8a62\u4e2d\u5305\u542b\u6392\u5e8f\u6216\u5206\u7d44\u64cd\u4f5c\uff0c\u5247\u61c9\u8003\u616e\u70ba\u76f8\u95dc\u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT customer_id, COUNT(*) FROM orders GROUP BY customer_id ORDER BY COUNT(*) DESC;<\/code><\/pre>\n<p>\u5728\u9019\u7a2e\u60c5\u6cc1\u4e0b\uff0c\u70ba <code>customer_id<\/code> \u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u5206\u7d44\u548c\u6392\u5e8f\u7684\u6548\u7387\u3002<\/p>\n<h2 id=\"%e5%bb%ba%e7%ab%8b%e7%b4%a2%e5%bc%95%e7%9a%84%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-gelmhiBHUl\">\u5efa\u7acb\u7d22\u5f15\u7684\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u96d6\u7136\u7d22\u5f15\u80fd\u5920\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\uff0c\u4f46\u904e\u591a\u7684\u7d22\u5f15\u4e5f\u6703\u5f71\u97ff\u8cc7\u6599\u5eab\u7684\u5beb\u5165\u6027\u80fd\u3002\u6bcf\u7576\u9032\u884c\u63d2\u5165\u3001\u66f4\u65b0\u6216\u522a\u9664\u64cd\u4f5c\u6642\uff0c\u7d22\u5f15\u4e5f\u9700\u8981\u88ab\u66f4\u65b0\u3002\u56e0\u6b64\uff0c\u5728\u5efa\u7acb\u7d22\u5f15\u6642\u61c9\u8b39\u614e\u8003\u616e\uff1a<\/p>\n<ul>\n<li>\u907f\u514d\u70ba\u6bcf\u500b\u6b04\u4f4d\u5efa\u7acb\u7d22\u5f15\uff0c\u61c9\u6839\u64da\u5be6\u969b\u67e5\u8a62\u9700\u6c42\u9032\u884c\u9078\u64c7\u3002<\/li>\n<li>\u5b9a\u671f\u6aa2\u67e5\u548c\u512a\u5316\u7d22\u5f15\uff0c\u522a\u9664\u4e0d\u518d\u4f7f\u7528\u7684\u7d22\u5f15\u3002<\/li>\n<li>\u8003\u616e\u4f7f\u7528\u8907\u5408\u7d22\u5f15\u4f86\u63d0\u9ad8\u591a\u500b\u6b04\u4f4d\u67e5\u8a62\u7684\u6548\u7387\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-gelmhiBHUl\">\u7e3d\u7d50<\/h2>\n<p>\u5728 MySQL \u4e2d\uff0c\u5efa\u7acb\u7d22\u5f15\u662f\u4e00\u9805\u91cd\u8981\u7684\u6027\u80fd\u512a\u5316\u6280\u8853\u3002\u9069\u7576\u7684\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u578b\u8cc7\u6599\u8868\u548c\u8907\u96dc\u67e5\u8a62\u6642\u3002\u4e86\u89e3\u4f55\u6642\u5efa\u7acb\u7d22\u5f15\u4ee5\u53ca\u5982\u4f55\u6709\u6548\u7ba1\u7406\u7d22\u5f15\uff0c\u5c0d\u65bc\u7dad\u6301\u8cc7\u6599\u5eab\u7684\u9ad8\u6548\u904b\u884c\u81f3\u95dc\u91cd\u8981\u3002\u82e5\u60a8\u9700\u8981\u9032\u4e00\u6b65\u4e86\u89e3 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u53ca\u5176\u76f8\u95dc\u670d\u52d9\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u8cc7\u8a0a\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u4f55\u6642\u5728 MySQL \u4e2d\u5efa\u7acb\u7d22\u5f15\uff0c\u4ee5\u63d0\u5347\u67e5\u8a62\u6548\u80fd\uff0c\u512a\u5316\u8cc7\u6599\u5eab\u6027\u80fd\uff0c\u4e26\u6e1b\u5c11\u67e5\u8a62\u6642\u9593\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-76036","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76036","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=76036"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76036\/revisions"}],"predecessor-version":[{"id":76037,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76036\/revisions\/76037"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=76036"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=76036"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=76036"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}