{"id":186442,"date":"2024-11-11T05:57:20","date_gmt":"2024-11-10T21:57:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/186442\/"},"modified":"2024-11-11T05:57:21","modified_gmt":"2024-11-10T21:57:21","slug":"%e6%95%b8%e6%93%9a%e5%ba%ab%e8%aa%bf%e5%84%aa%e7%a9%8d%e7%b4%af%e7%b3%bb%e5%88%97%ef%bc%882%ef%bc%89%ef%bc%9a%e6%9f%a5%e8%a9%a2","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/186442\/","title":{"rendered":"\u6578\u64da\u5eab\u8abf\u512a\u7a4d\u7d2f\u7cfb\u5217\uff082\uff09\uff1a\u67e5\u8a62"},"content":{"rendered":"<h1 id=\"%e6%95%b8%e6%93%9a%e5%ba%ab%e8%aa%bf%e5%84%aa%e7%a9%8d%e7%b4%af%e7%b3%bb%e5%88%97%ef%bc%882%ef%bc%89%ef%bc%9a%e6%9f%a5%e8%a9%a2-LGyAyzijUL\">\u6578\u64da\u5eab\u8abf\u512a\u7a4d\u7d2f\u7cfb\u5217\uff082\uff09\uff1a\u67e5\u8a62<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u67e5\u8a62\u7684\u6027\u80fd\u512a\u5316\u662f\u63d0\u5347\u6574\u9ad4\u7cfb\u7d71\u6548\u7387\u7684\u95dc\u9375\u56e0\u7d20\u4e4b\u4e00\u3002\u96a8\u8457\u6578\u64da\u91cf\u7684\u589e\u9577\uff0c\u5982\u4f55\u6709\u6548\u5730\u57f7\u884c\u67e5\u8a62\u4ee5\u7372\u53d6\u6240\u9700\u6578\u64da\uff0c\u6210\u70ba\u4e86\u6bcf\u4f4d\u6578\u64da\u5eab\u7ba1\u7406\u54e1\u5fc5\u9808\u9762\u5c0d\u7684\u6311\u6230\u3002\u672c\u7bc7\u6587\u7ae0\u5c07\u63a2\u8a0e\u67e5\u8a62\u512a\u5316\u7684\u57fa\u672c\u6982\u5ff5\u3001\u5e38\u898b\u554f\u984c\u53ca\u5176\u89e3\u6c7a\u65b9\u6848\u3002<\/p>\n<h2 id=\"%e6%9f%a5%e8%a9%a2%e5%84%aa%e5%8c%96%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-LGyAyzijUL\">\u67e5\u8a62\u512a\u5316\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>\u67e5\u8a62\u512a\u5316\u662f\u6307\u901a\u904e\u6539\u9032\u67e5\u8a62\u8a9e\u53e5\u7684\u7d50\u69cb\u548c\u57f7\u884c\u8a08\u5283\uff0c\u4ee5\u63d0\u9ad8\u67e5\u8a62\u7684\u57f7\u884c\u6548\u7387\u3002\u6578\u64da\u5eab\u7cfb\u7d71\u901a\u5e38\u6703\u81ea\u52d5\u751f\u6210\u67e5\u8a62\u7684\u57f7\u884c\u8a08\u5283\uff0c\u4f46\u9019\u4e26\u4e0d\u7e3d\u662f\u6700\u512a\u7684\u3002\u56e0\u6b64\uff0c\u4e86\u89e3\u5982\u4f55\u624b\u52d5\u512a\u5316\u67e5\u8a62\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002<\/p>\n<h2 id=\"%e5%b8%b8%e8%a6%8b%e7%9a%84%e6%9f%a5%e8%a9%a2%e6%80%a7%e8%83%bd%e5%95%8f%e9%a1%8c-LGyAyzijUL\">\u5e38\u898b\u7684\u67e5\u8a62\u6027\u80fd\u554f\u984c<\/h2>\n<ul>\n<li><strong>\u5168\u8868\u6383\u63cf\uff1a<\/strong>\u7576\u67e5\u8a62\u672a\u80fd\u5229\u7528\u7d22\u5f15\u6642\uff0c\u6578\u64da\u5eab\u6703\u9032\u884c\u5168\u8868\u6383\u63cf\uff0c\u9019\u6703\u5c0e\u81f4\u6027\u80fd\u4e0b\u964d\u3002<\/li>\n<li><strong>\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u6aa2\u7d22\uff1a<\/strong>\u67e5\u8a62\u4e2d\u9078\u64c7\u4e86\u904e\u591a\u7684\u5217\u6216\u884c\uff0c\u5c0e\u81f4\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u50b3\u8f38\u3002<\/li>\n<li><strong>\u8907\u96dc\u7684\u806f\u63a5\u64cd\u4f5c\uff1a<\/strong>\u591a\u8868\u806f\u63a5\u6642\uff0c\u5982\u679c\u6c92\u6709\u9069\u7576\u7684\u7d22\u5f15\uff0c\u6703\u5c0e\u81f4\u67e5\u8a62\u901f\u5ea6\u8b8a\u6162\u3002<\/li>\n<li><strong>\u4e0d\u7576\u7684\u6578\u64da\u985e\u578b\u4f7f\u7528\uff1a<\/strong>\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528\u4e0d\u5339\u914d\u7684\u6578\u64da\u985e\u578b\uff0c\u53ef\u80fd\u6703\u5c0e\u81f4\u6027\u80fd\u554f\u984c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e6%9f%a5%e8%a9%a2%e5%84%aa%e5%8c%96%e7%9a%84%e7%ad%96%e7%95%a5-LGyAyzijUL\">\u67e5\u8a62\u512a\u5316\u7684\u7b56\u7565<\/h2>\n<h3 id=\"1-%e4%bd%bf%e7%94%a8%e7%b4%a2%e5%bc%95-LGyAyzijUL\">1. \u4f7f\u7528\u7d22\u5f15<\/h3>\n<p>\u7d22\u5f15\u662f\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u7684\u6700\u6709\u6548\u5de5\u5177\u4e4b\u4e00\u3002\u901a\u904e\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528\u7d22\u5f15\uff0c\u53ef\u4ee5\u986f\u8457\u6e1b\u5c11\u67e5\u8a62\u7684\u57f7\u884c\u6642\u9593\u3002\u4ee5\u4e0b\u662f\u5275\u5efa\u7d22\u5f15\u7684\u57fa\u672c\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>CREATE INDEX index_name ON table_name (column_name);<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c0d\u65bc\u4e00\u500b\u7528\u6236\u8868\uff0c\u5982\u679c\u7d93\u5e38\u6839\u64da\u7528\u6236\u540d\u67e5\u8a62\uff0c\u53ef\u4ee5\u9019\u6a23\u5275\u5efa\u7d22\u5f15\uff1a<\/p>\n<pre><code>CREATE INDEX idx_username ON users (username);<\/code><\/pre>\n<h3 id=\"2-%e7%b2%be%e7%b0%a1%e6%9f%a5%e8%a9%a2%e8%aa%9e%e5%8f%a5-LGyAyzijUL\">2. \u7cbe\u7c21\u67e5\u8a62\u8a9e\u53e5<\/h3>\n<p>\u5728\u64b0\u5beb\u67e5\u8a62\u6642\uff0c\u61c9\u8a72\u53ea\u9078\u64c7\u5fc5\u8981\u7684\u5217\u548c\u884c\u3002\u4f7f\u7528 <code>SELECT<\/code> \u8a9e\u53e5\u6642\uff0c\u907f\u514d\u4f7f\u7528 <code>SELECT *<\/code>\uff0c\u800c\u662f\u660e\u78ba\u6307\u5b9a\u6240\u9700\u7684\u5217\uff1a<\/p>\n<pre><code>SELECT id, username FROM users WHERE status = 'active';<\/code><\/pre>\n<h3 id=\"3-%e5%84%aa%e5%8c%96%e8%81%af%e6%8e%a5%e6%93%8d%e4%bd%9c-LGyAyzijUL\">3. \u512a\u5316\u806f\u63a5\u64cd\u4f5c<\/h3>\n<p>\u5728\u9032\u884c\u591a\u8868\u806f\u63a5\u6642\uff0c\u61c9\u78ba\u4fdd\u6240\u6709\u53c3\u8207\u806f\u63a5\u7684\u5217\u90fd\u6709\u7d22\u5f15\u3002\u4f7f\u7528 <code>INNER JOIN<\/code> \u800c\u975e <code>OUTER JOIN<\/code>\uff0c\u5982\u679c\u4e0d\u9700\u8981\u6240\u6709\u6578\u64da\u7684\u8a71\uff0c\u9019\u6a23\u53ef\u4ee5\u63d0\u9ad8\u6027\u80fd\uff1a<\/p>\n<pre><code>SELECT u.id, o.order_id \nFROM users u \nINNER JOIN orders o ON u.id = o.user_id \nWHERE u.status = 'active';<\/code><\/pre>\n<h3 id=\"4-%e4%bd%bf%e7%94%a8%e6%9f%a5%e8%a9%a2%e5%88%86%e6%9e%90%e5%b7%a5%e5%85%b7-LGyAyzijUL\">4. \u4f7f\u7528\u67e5\u8a62\u5206\u6790\u5de5\u5177<\/h3>\n<p>\u8a31\u591a\u6578\u64da\u5eab\u7cfb\u7d71\u63d0\u4f9b\u4e86\u67e5\u8a62\u5206\u6790\u5de5\u5177\uff0c\u53ef\u4ee5\u5e6b\u52a9\u8b58\u5225\u6027\u80fd\u74f6\u9838\u3002\u4f8b\u5982\uff0cMySQL \u7684 <code>EXPLAIN<\/code> \u8a9e\u53e5\u53ef\u4ee5\u986f\u793a\u67e5\u8a62\u7684\u57f7\u884c\u8a08\u5283\uff1a<\/p>\n<pre><code>EXPLAIN SELECT * FROM users WHERE status = 'active';<\/code><\/pre>\n<p>\u901a\u904e\u5206\u6790\u57f7\u884c\u8a08\u5283\uff0c\u53ef\u4ee5\u4e86\u89e3\u67e5\u8a62\u7684\u904b\u884c\u65b9\u5f0f\uff0c\u4e26\u91dd\u5c0d\u6027\u5730\u9032\u884c\u512a\u5316\u3002<\/p>\n<h2 id=\"%e7%b5%90%e8%ab%96-LGyAyzijUL\">\u7d50\u8ad6<\/h2>\n<p>\u67e5\u8a62\u512a\u5316\u662f\u4e00\u500b\u6301\u7e8c\u7684\u904e\u7a0b\uff0c\u96a8\u8457\u6578\u64da\u91cf\u7684\u589e\u9577\u548c\u696d\u52d9\u9700\u6c42\u7684\u8b8a\u5316\uff0c\u67e5\u8a62\u7684\u6027\u80fd\u4e5f\u9700\u8981\u4e0d\u65b7\u5730\u9032\u884c\u8abf\u6574\u548c\u512a\u5316\u3002\u901a\u904e\u5408\u7406\u4f7f\u7528\u7d22\u5f15\u3001\u7cbe\u7c21\u67e5\u8a62\u8a9e\u53e5\u3001\u512a\u5316\u806f\u63a5\u64cd\u4f5c\u4ee5\u53ca\u5229\u7528\u67e5\u8a62\u5206\u6790\u5de5\u5177\uff0c\u6578\u64da\u5eab\u7ba1\u7406\u54e1\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u7684\u57f7\u884c\u6548\u7387\u3002<\/p>\n<p>\u5728\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\u6642\uff0c\u8003\u616e\u5230\u6027\u80fd\u548c\u53ef\u64f4\u5c55\u6027\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u82e5\u60a8\u9700\u8981\u9032\u4e00\u6b65\u4e86\u89e3\u5982\u4f55\u5728\u9999\u6e2f\u9078\u64c7\u5408\u9069\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \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>\u63a2\u7d22\u6578\u64da\u5eab\u8abf\u512a\u7684\u7b2c\u4e8c\u90e8\u5206\uff0c\u6df1\u5165\u5206\u6790\u67e5\u8a62\u6027\u80fd\uff0c\u63d0\u4f9b\u6700\u4f73\u5be6\u8e10\u548c\u6280\u5de7\uff0c\u63d0\u5347\u6578\u64da\u8655\u7406\u6548\u7387\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-186442","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186442","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=186442"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186442\/revisions"}],"predecessor-version":[{"id":186443,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186442\/revisions\/186443"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=186442"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=186442"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=186442"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}