{"id":193449,"date":"2024-11-12T22:16:19","date_gmt":"2024-11-12T14:16:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/193449\/"},"modified":"2024-11-12T22:16:20","modified_gmt":"2024-11-12T14:16:20","slug":"%e5%ad%b8%e7%bf%92mysql%e5%a6%82%e4%bd%95%e6%9f%a5%e7%9c%8b%e6%95%b8%e6%93%9a%e5%ba%ab%e7%b4%a2%e5%bc%95-mysql%e6%9f%a5%e7%9c%8b%e6%95%b8%e6%93%9a%e5%ba%ab%e7%b4%a2%e5%bc%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/193449\/","title":{"rendered":"\u5b78\u7fd2MySQL\u5982\u4f55\u67e5\u770b\u6578\u64da\u5eab\u7d22\u5f15 (mysql\u67e5\u770b\u6578\u64da\u5eab\u7d22\u5f15)"},"content":{"rendered":"<h1 id=\"%e5%ad%b8%e7%bf%92mysql%e5%a6%82%e4%bd%95%e6%9f%a5%e7%9c%8b%e6%95%b8%e6%93%9a%e5%ba%ab%e7%b4%a2%e5%bc%95-GYBPCZpYxm\">\u5b78\u7fd2MySQL\u5982\u4f55\u67e5\u770b\u6578\u64da\u5eab\u7d22\u5f15<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u7d22\u5f15\u662f\u4e00\u500b\u81f3\u95dc\u91cd\u8981\u7684\u6982\u5ff5\u3002\u5b83\u80fd\u5920\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u7684\u6548\u7387\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\u3002MySQL\u4f5c\u70ba\u4e00\u500b\u6d41\u884c\u7684\u958b\u6e90\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\uff0c\u63d0\u4f9b\u4e86\u591a\u7a2e\u65b9\u6cd5\u4f86\u67e5\u770b\u548c\u7ba1\u7406\u6578\u64da\u5eab\u7d22\u5f15\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u5982\u4f55\u5728MySQL\u4e2d\u67e5\u770b\u6578\u64da\u5eab\u7d22\u5f15\uff0c\u5e6b\u52a9\u60a8\u66f4\u597d\u5730\u7406\u89e3\u548c\u512a\u5316\u6578\u64da\u5eab\u6027\u80fd\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e6%95%b8%e6%93%9a%e5%ba%ab%e7%b4%a2%e5%bc%95%ef%bc%9f-GYBPCZpYxm\">\u4ec0\u9ebc\u662f\u6578\u64da\u5eab\u7d22\u5f15\uff1f<\/h2>\n<p>\u6578\u64da\u5eab\u7d22\u5f15\u662f\u4e00\u7a2e\u6578\u64da\u7d50\u69cb\uff0c\u65e8\u5728\u63d0\u9ad8\u67e5\u8a62\u64cd\u4f5c\u7684\u901f\u5ea6\u3002\u5b83\u985e\u4f3c\u65bc\u66f8\u7c4d\u7684\u76ee\u9304\uff0c\u80fd\u5920\u5e6b\u52a9\u6578\u64da\u5eab\u5feb\u901f\u5b9a\u4f4d\u5230\u6240\u9700\u7684\u6578\u64da\u3002\u7d22\u5f15\u53ef\u4ee5\u57fa\u65bc\u4e00\u500b\u6216\u591a\u500b\u5217\u5275\u5efa\uff0c\u4e26\u4e14\u53ef\u4ee5\u662f\u552f\u4e00\u7684\u6216\u975e\u552f\u4e00\u7684\u3002\u4f7f\u7528\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u6e1b\u5c11\u67e5\u8a62\u7684\u57f7\u884c\u6642\u9593\uff0c\u7279\u5225\u662f\u5728\u5927\u578b\u6578\u64da\u96c6\u4e0a\u3002<\/p>\n<h2 id=\"%e5%a6%82%e4%bd%95%e6%9f%a5%e7%9c%8bmysql%e4%b8%ad%e7%9a%84%e7%b4%a2%e5%bc%95-GYBPCZpYxm\">\u5982\u4f55\u67e5\u770bMySQL\u4e2d\u7684\u7d22\u5f15<\/h2>\n<p>\u5728MySQL\u4e2d\uff0c\u6709\u5e7e\u7a2e\u65b9\u6cd5\u53ef\u4ee5\u67e5\u770b\u6578\u64da\u5eab\u4e2d\u7684\u7d22\u5f15\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u7528\u7684\u65b9\u6cd5\uff1a<\/p>\n<h3 id=\"1-%e4%bd%bf%e7%94%a8show-index%e5%91%bd%e4%bb%a4-GYBPCZpYxm\">1. \u4f7f\u7528SHOW INDEX\u547d\u4ee4<\/h3>\n<p>\u6700\u76f4\u63a5\u7684\u65b9\u6cd5\u662f\u4f7f\u7528<code>SHOW INDEX<\/code>\u547d\u4ee4\u3002\u9019\u500b\u547d\u4ee4\u53ef\u4ee5\u986f\u793a\u6307\u5b9a\u8868\u7684\u6240\u6709\u7d22\u5f15\u4fe1\u606f\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528\u793a\u4f8b\uff1a<\/p>\n<pre><code>SHOW INDEX FROM \u8868\u540d;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5982\u679c\u60a8\u6709\u4e00\u500b\u540d\u70ba<code>users<\/code>\u7684\u8868\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\u67e5\u770b\u5176\u7d22\u5f15\uff1a<\/p>\n<pre><code>SHOW INDEX FROM users;<\/code><\/pre>\n<p>\u9019\u5c07\u8fd4\u56de\u4e00\u500b\u7d50\u679c\u96c6\uff0c\u5176\u4e2d\u5305\u542b\u7d22\u5f15\u7684\u540d\u7a31\u3001\u985e\u578b\u3001\u552f\u4e00\u6027\u3001\u7d22\u5f15\u5217\u7b49\u4fe1\u606f\u3002<\/p>\n<h3 id=\"2-%e4%bd%bf%e7%94%a8information_schema-GYBPCZpYxm\">2. \u4f7f\u7528INFORMATION_SCHEMA<\/h3>\n<p>MySQL\u9084\u63d0\u4f9b\u4e86\u4e00\u500b\u540d\u70ba<code>INFORMATION_SCHEMA<\/code>\u7684\u865b\u64ec\u6578\u64da\u5eab\uff0c\u60a8\u53ef\u4ee5\u901a\u904e\u67e5\u8a62\u9019\u500b\u6578\u64da\u5eab\u4f86\u7372\u53d6\u7d22\u5f15\u4fe1\u606f\u3002\u4ee5\u4e0b\u662f\u67e5\u8a62\u7d22\u5f15\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_NAME = '\u8868\u540d';<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u8981\u67e5\u770b<code>users<\/code>\u8868\u7684\u7d22\u5f15\uff0c\u60a8\u53ef\u4ee5\u57f7\u884c\uff1a<\/p>\n<pre><code>SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE TABLE_NAME = 'users';<\/code><\/pre>\n<p>\u9019\u5c07\u8fd4\u56de\u8207<code>SHOW INDEX<\/code>\u547d\u4ee4\u985e\u4f3c\u7684\u7d50\u679c\uff0c\u4f46\u63d0\u4f9b\u4e86\u66f4\u591a\u7684\u4e0a\u4e0b\u6587\u4fe1\u606f\u3002<\/p>\n<h3 id=\"3-%e4%bd%bf%e7%94%a8explain%e5%91%bd%e4%bb%a4-GYBPCZpYxm\">3. \u4f7f\u7528EXPLAIN\u547d\u4ee4<\/h3>\n<p>\u5728\u9032\u884c\u67e5\u8a62\u6642\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528<code>EXPLAIN<\/code>\u547d\u4ee4\u4f86\u67e5\u770bMySQL\u5982\u4f55\u4f7f\u7528\u7d22\u5f15\u4f86\u57f7\u884c\u67e5\u8a62\u3002\u9019\u5c0d\u65bc\u512a\u5316\u67e5\u8a62\u6027\u80fd\u975e\u5e38\u6709\u5e6b\u52a9\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528\u793a\u4f8b\uff1a<\/p>\n<pre><code>EXPLAIN SELECT * FROM users WHERE age = 30;<\/code><\/pre>\n<p>\u9019\u5c07\u986f\u793aMySQL\u5728\u57f7\u884c\u67e5\u8a62\u6642\u6240\u4f7f\u7528\u7684\u7d22\u5f15\u53ca\u5176\u6548\u7387\u3002<\/p>\n<h2 id=\"%e7%b4%a2%e5%bc%95%e7%9a%84%e6%9c%80%e4%bd%b3%e5%af%a6%e8%b8%90-GYBPCZpYxm\">\u7d22\u5f15\u7684\u6700\u4f73\u5be6\u8e10<\/h2>\n<p>\u5728\u4f7f\u7528\u7d22\u5f15\u6642\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e9b\u6700\u4f73\u5be6\u8e10\uff1a<\/p>\n<ul>\n<li>\u907f\u514d\u5728\u4f4e\u57fa\u6578\u5217\u4e0a\u5275\u5efa\u7d22\u5f15\uff0c\u56e0\u70ba\u9019\u6a23\u7684\u7d22\u5f15\u53ef\u80fd\u4e0d\u6703\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002<\/li>\n<li>\u5b9a\u671f\u6aa2\u67e5\u548c\u7dad\u8b77\u7d22\u5f15\uff0c\u522a\u9664\u4e0d\u518d\u4f7f\u7528\u7684\u7d22\u5f15\u3002<\/li>\n<li>\u5728\u5275\u5efa\u7d22\u5f15\u6642\uff0c\u8003\u616e\u67e5\u8a62\u7684\u983b\u7387\u548c\u985e\u578b\uff0c\u4ee5\u78ba\u4fdd\u7d22\u5f15\u7684\u6709\u6548\u6027\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-GYBPCZpYxm\">\u7e3d\u7d50<\/h2>\n<p>\u4e86\u89e3\u5982\u4f55\u67e5\u770b\u548c\u7ba1\u7406MySQL\u4e2d\u7684\u6578\u64da\u5eab\u7d22\u5f15\u5c0d\u65bc\u512a\u5316\u6578\u64da\u5eab\u6027\u80fd\u81f3\u95dc\u91cd\u8981\u3002\u901a\u904e\u4f7f\u7528<code>SHOW INDEX<\/code>\u3001<code>INFORMATION_SCHEMA<\/code>\u548c<code>EXPLAIN<\/code>\u7b49\u5de5\u5177\uff0c\u60a8\u53ef\u4ee5\u7372\u5f97\u6709\u95dc\u7d22\u5f15\u7684\u8a73\u7d30\u4fe1\u606f\uff0c\u4e26\u6839\u64da\u9700\u8981\u9032\u884c\u8abf\u6574\u3002\u9019\u4e0d\u50c5\u80fd\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\uff0c\u9084\u80fd\u6539\u5584\u6574\u9ad4\u7cfb\u7d71\u6027\u80fd\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u670d\u52d9\uff0c\u9019\u5c07\u70ba\u60a8\u7684\u61c9\u7528\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u548c\u512a\u5316\u7684\u6027\u80fd\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u5728MySQL\u4e2d\u67e5\u770b\u6578\u64da\u5eab\u7d22\u5f15\uff0c\u638c\u63e1\u67e5\u8a62\u548c\u7ba1\u7406\u7d22\u5f15\u7684\u6280\u5de7\uff0c\u63d0\u5347\u6578\u64da\u5eab\u6027\u80fd\u548c\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-193449","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/193449","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=193449"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/193449\/revisions"}],"predecessor-version":[{"id":193450,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/193449\/revisions\/193450"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=193449"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=193449"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=193449"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}