{"id":923174,"date":"2024-06-09T08:10:35","date_gmt":"2024-06-09T08:10:35","guid":{"rendered":"https:\/\/proxyelite.info\/?p=923174"},"modified":"2024-06-09T08:10:36","modified_gmt":"2024-06-09T08:10:36","slug":"what-is-selectivity-in-a-database","status":"publish","type":"post","link":"https:\/\/proxyelite.info\/cn\/what-is-selectivity-in-a-database\/","title":{"rendered":"\u6570\u636e\u5e93\u4e2d\u7684\u9009\u62e9\u6027\u662f\u4ec0\u4e48\uff1f"},"content":{"rendered":"<p class=\"wp-block-paragraph\">\u4e86\u89e3\u6570\u636e\u5e93\u4e2d\u7684\u9009\u62e9\u6027\u6982\u5ff5\u5bf9\u4e8e\u4f18\u5316\u6570\u636e\u68c0\u7d22\u548c\u786e\u4fdd\u9ad8\u6548\u7684\u6570\u636e\u5e93\u6027\u80fd\u81f3\u5173\u91cd\u8981\u3002\u672c\u6587\u89e3\u91ca\u4e86\u4ec0\u4e48\u662f\u9009\u62e9\u6027\u3001\u4e3a\u4ec0\u4e48\u9009\u62e9\u6027\u5f88\u91cd\u8981\u4ee5\u53ca\u5982\u4f55\u8861\u91cf\u548c\u6539\u8fdb\u9009\u62e9\u6027\u3002<\/p>\n\n\n\n<h2 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This article explains what selectivity is, why it is important, and how it can be measured and improved. Definition and Basics Selectivity in a database context refers to the efficiency with which a query or an index [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":923177,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-923174","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-articles"],"acf":[],"_links":{"self":[{"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/posts\/923174","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/comments?post=923174"}],"version-history":[{"count":0,"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/posts\/923174\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/media\/923177"}],"wp:attachment":[{"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/media?parent=923174"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/categories?post=923174"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/proxyelite.info\/cn\/wp-json\/wp\/v2\/tags?post=923174"}],"curies":[{"name":"\u53ef\u6e7f\u6027\u7c89\u5242","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}