{"id":162983,"date":"2024-11-04T19:40:23","date_gmt":"2024-11-04T11:40:23","guid":{"rendered":"https:\/\/server.hk\/cnblog\/162983\/"},"modified":"2024-11-04T19:40:23","modified_gmt":"2024-11-04T11:40:23","slug":"%e6%95%99%e6%82%a8%e5%9c%a8mysql%e6%9f%a5%e6%89%be%e6%95%88%e7%8e%87%e6%85%a2%e7%9a%84sql%e8%aa%9e%e5%8f%a5","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/162983\/","title":{"rendered":"\u6559\u60a8\u5728mysql\u67e5\u627e\u6548\u7387\u6162\u7684SQL\u8a9e\u53e5"},"content":{"rendered":"<h1 id=\"%e6%95%99%e6%82%a8%e5%9c%a8mysql%e6%9f%a5%e6%89%be%e6%95%88%e7%8e%87%e6%85%a2%e7%9a%84sql%e8%aa%9e%e5%8f%a5-qlXpUvBFoB\">\u6559\u60a8\u5728MySQL\u67e5\u627e\u6548\u7387\u6162\u7684SQL\u8a9e\u53e5<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cSQL\u8a9e\u53e5\u7684\u57f7\u884c\u6548\u7387\u5c0d\u65bc\u6574\u9ad4\u7cfb\u7d71\u6027\u80fd\u81f3\u95dc\u91cd\u8981\u3002\u7576\u6211\u5011\u7684\u61c9\u7528\u7a0b\u5e8f\u9762\u81e8\u6027\u80fd\u74f6\u9838\u6642\uff0c\u901a\u5e38\u9700\u8981\u6aa2\u67e5SQL\u67e5\u8a62\u7684\u6548\u7387\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u5982\u4f55\u5728MySQL\u4e2d\u67e5\u627e\u6548\u7387\u6162\u7684SQL\u8a9e\u53e5\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u512a\u5316\u5efa\u8b70\u3002<\/p>\n<h2 id=\"1-%e4%bd%bf%e7%94%a8%e6%85%a2%e6%9f%a5%e8%a9%a2%e6%97%a5%e8%aa%8c-qlXpUvBFoB\">1. \u4f7f\u7528\u6162\u67e5\u8a62\u65e5\u8a8c<\/h2>\n<p>MySQL\u63d0\u4f9b\u4e86\u4e00\u500b\u540d\u70ba\u300c\u6162\u67e5\u8a62\u65e5\u8a8c\u300d\u7684\u529f\u80fd\uff0c\u53ef\u4ee5\u5e6b\u52a9\u6211\u5011\u8b58\u5225\u57f7\u884c\u6642\u9593\u8d85\u904e\u7279\u5b9a\u95be\u503c\u7684\u67e5\u8a62\u3002\u8981\u555f\u7528\u6162\u67e5\u8a62\u65e5\u8a8c\uff0c\u53ef\u4ee5\u5728MySQL\u914d\u7f6e\u6587\u4ef6\u4e2d\u6dfb\u52a0\u4ee5\u4e0b\u8a2d\u7f6e\uff1a<\/p>\n<pre><code>\n[mysqld]\nslow_query_log = 1\nslow_query_log_file = \/var\/log\/mysql\/slow-query.log\nlong_query_time = 2\n<\/code><\/pre>\n<p>\u4e0a\u8ff0\u8a2d\u7f6e\u5c07\u8a18\u9304\u6240\u6709\u57f7\u884c\u6642\u9593\u8d85\u904e2\u79d2\u7684\u67e5\u8a62\u3002\u555f\u7528\u5f8c\uff0c\u60a8\u53ef\u4ee5\u901a\u904e\u67e5\u770b\u65e5\u8a8c\u6587\u4ef6\u4f86\u8b58\u5225\u6162\u67e5\u8a62\u3002<\/p>\n<h2 id=\"2-%e4%bd%bf%e7%94%a8explain%e5%91%bd%e4%bb%a4-qlXpUvBFoB\">2. \u4f7f\u7528EXPLAIN\u547d\u4ee4<\/h2>\n<p>\u5728MySQL\u4e2d\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528EXPLAIN\u547d\u4ee4\u4f86\u5206\u6790\u67e5\u8a62\u7684\u57f7\u884c\u8a08\u5283\u3002\u9019\u53ef\u4ee5\u5e6b\u52a9\u60a8\u4e86\u89e3\u67e5\u8a62\u662f\u5982\u4f55\u57f7\u884c\u7684\uff0c\u4e26\u627e\u51fa\u6f5b\u5728\u7684\u6027\u80fd\u554f\u984c\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528EXPLAIN\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>\nEXPLAIN SELECT * FROM users WHERE age &gt; 30;\n<\/code><\/pre>\n<p>\u57f7\u884c\u6b64\u547d\u4ee4\u5f8c\uff0cMySQL\u5c07\u8fd4\u56de\u4e00\u500b\u8868\u683c\uff0c\u986f\u793a\u67e5\u8a62\u7684\u57f7\u884c\u8a08\u5283\uff0c\u5305\u62ec\u4f7f\u7528\u7684\u7d22\u5f15\u3001\u884c\u6578\u4f30\u7b97\u7b49\u4fe1\u606f\u3002\u6839\u64da\u9019\u4e9b\u4fe1\u606f\uff0c\u60a8\u53ef\u4ee5\u9032\u4e00\u6b65\u512a\u5316\u67e5\u8a62\u3002<\/p>\n<h2 id=\"3-%e6%aa%a2%e6%9f%a5%e7%b4%a2%e5%bc%95%e7%9a%84%e4%bd%bf%e7%94%a8%e6%83%85%e6%b3%81-qlXpUvBFoB\">3. \u6aa2\u67e5\u7d22\u5f15\u7684\u4f7f\u7528\u60c5\u6cc1<\/h2>\n<p>\u7d22\u5f15\u662f\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u7684\u95dc\u9375\u56e0\u7d20\u4e4b\u4e00\u3002\u78ba\u4fdd\u60a8\u7684\u67e5\u8a62\u4f7f\u7528\u4e86\u9069\u7576\u7684\u7d22\u5f15\uff0c\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u57f7\u884c\u6548\u7387\u3002\u60a8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\u67e5\u770b\u8868\u7684\u7d22\u5f15\uff1a<\/p>\n<pre><code>\nSHOW INDEX FROM users;\n<\/code><\/pre>\n<p>\u5982\u679c\u767c\u73fe\u67d0\u4e9b\u67e5\u8a62\u672a\u4f7f\u7528\u7d22\u5f15\uff0c\u60a8\u53ef\u4ee5\u8003\u616e\u6dfb\u52a0\u7d22\u5f15\u3002\u4f8b\u5982\uff0c\u5c0d\u65bc\u7d93\u5e38\u7528\u65bc\u67e5\u8a62\u7684\u5217\uff0c\u53ef\u4ee5\u5275\u5efa\u7d22\u5f15\uff1a<\/p>\n<pre><code>\nCREATE INDEX idx_age ON users(age);\n<\/code><\/pre>\n<h2 id=\"4-%e5%84%aa%e5%8c%96%e6%9f%a5%e8%a9%a2%e8%aa%9e%e5%8f%a5-qlXpUvBFoB\">4. \u512a\u5316\u67e5\u8a62\u8a9e\u53e5<\/h2>\n<p>\u6709\u6642\u5019\uff0c\u67e5\u8a62\u8a9e\u53e5\u672c\u8eab\u53ef\u80fd\u5b58\u5728\u554f\u984c\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u512a\u5316\u67e5\u8a62\u7684\u5efa\u8b70\uff1a<\/p>\n<ul>\n<li>\u907f\u514d\u4f7f\u7528SELECT *\uff0c\u53ea\u9078\u64c7\u9700\u8981\u7684\u5217\u3002<\/li>\n<li>\u4f7f\u7528JOIN\u800c\u4e0d\u662f\u5b50\u67e5\u8a62\uff0c\u901a\u5e38JOIN\u7684\u6027\u80fd\u66f4\u597d\u3002<\/li>\n<li>\u4f7f\u7528LIMIT\u9650\u5236\u8fd4\u56de\u7684\u884c\u6578\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\u3002<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u5c07\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>\nSELECT * FROM orders WHERE user_id = 1;\n<\/code><\/pre>\n<p>\u512a\u5316\u70ba\uff1a<\/p>\n<pre><code>\nSELECT order_id, order_date FROM orders WHERE user_id = 1;\n<\/code><\/pre>\n<h2 id=\"5-%e5%ae%9a%e6%9c%9f%e7%b6%ad%e8%ad%b7%e6%95%b8%e6%93%9a%e5%ba%ab-qlXpUvBFoB\">5. \u5b9a\u671f\u7dad\u8b77\u6578\u64da\u5eab<\/h2>\n<p>\u5b9a\u671f\u7dad\u8b77\u6578\u64da\u5eab\u53ef\u4ee5\u5e6b\u52a9\u63d0\u9ad8\u6027\u80fd\u3002\u9019\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u5b9a\u671f\u57f7\u884cOPTIMIZE TABLE\u547d\u4ee4\uff0c\u4ee5\u91cd\u5efa\u548c\u58d3\u7e2e\u8868\u3002<\/li>\n<li>\u6e05\u7406\u4e0d\u5fc5\u8981\u7684\u6578\u64da\uff0c\u6e1b\u5c11\u8868\u7684\u5927\u5c0f\u3002<\/li>\n<li>\u6aa2\u67e5\u548c\u4fee\u5fa9\u640d\u58de\u7684\u8868\u3002<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\u512a\u5316\u8868\uff1a<\/p>\n<pre><code>\nOPTIMIZE TABLE users;\n<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-qlXpUvBFoB\">\u7e3d\u7d50<\/h2>\n<p>\u5728MySQL\u4e2d\u67e5\u627e\u6548\u7387\u6162\u7684SQL\u8a9e\u53e5\u662f\u4e00\u500b\u91cd\u8981\u7684\u7dad\u8b77\u4efb\u52d9\u3002\u901a\u904e\u555f\u7528\u6162\u67e5\u8a62\u65e5\u8a8c\u3001\u4f7f\u7528EXPLAIN\u547d\u4ee4\u3001\u6aa2\u67e5\u7d22\u5f15\u3001\u512a\u5316\u67e5\u8a62\u8a9e\u53e5\u4ee5\u53ca\u5b9a\u671f\u7dad\u8b77\u6578\u64da\u5eab\uff0c\u60a8\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002\u9019\u4e9b\u65b9\u6cd5\u4e0d\u50c5\u80fd\u5e6b\u52a9\u60a8\u8b58\u5225\u554f\u984c\uff0c\u9084\u80fd\u63d0\u4f9b\u89e3\u6c7a\u65b9\u6848\uff0c\u5f9e\u800c\u63d0\u5347\u6574\u9ad4\u7cfb\u7d71\u7684\u6548\u7387\u3002\u5982\u679c\u60a8\u9700\u8981\u66f4\u9ad8\u6548\u7684\u6578\u64da\u8655\u7406\uff0c\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\u3002\u9019\u4e9b\u89e3\u6c7a\u65b9\u6848\u80fd\u5920\u63d0\u4f9b\u66f4\u597d\u7684\u6027\u80fd\u548c\u7a69\u5b9a\u6027\uff0c\u6eff\u8db3\u60a8\u7684\u696d\u52d9\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u5728MySQL\u4e2d\u67e5\u627e\u6548\u7387\u6162\u7684SQL\u8a9e\u53e5\uff0c\u63d0\u5347\u6578\u64da\u5eab\u6027\u80fd\uff0c\u512a\u5316\u67e5\u8a62\u901f\u5ea6\uff0c\u8b93\u60a8\u7684\u61c9\u7528\u904b\u884c\u66f4\u6d41\u66a2\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-162983","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/162983","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=162983"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/162983\/revisions"}],"predecessor-version":[{"id":162984,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/162983\/revisions\/162984"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=162983"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=162983"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=162983"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}