{"id":186218,"date":"2024-11-11T04:05:17","date_gmt":"2024-11-10T20:05:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/186218\/"},"modified":"2024-11-11T04:05:18","modified_gmt":"2024-11-10T20:05:18","slug":"%e6%95%b8%e6%93%9a%e5%ba%ab%e6%93%8d%e4%bd%9c%e4%b9%8b%e5%ad%b8%e7%94%9f%e8%a1%a8%e8%81%af%e6%8e%a5%e7%8f%ad%e7%b4%9a%e8%a1%a8%ef%bc%88%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%b8%e7%94%9f%e8%a1%a8%e9%80%a3","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/186218\/","title":{"rendered":"\u6578\u64da\u5eab\u64cd\u4f5c\u4e4b\u5b78\u751f\u8868\u806f\u63a5\u73ed\u7d1a\u8868\uff08\u6578\u64da\u5eab\u5b78\u751f\u8868\u9023\u73ed\u7d1a\u8868\uff09"},"content":{"rendered":"<h1 id=\"%e6%95%b8%e6%93%9a%e5%ba%ab%e6%93%8d%e4%bd%9c%e4%b9%8b%e5%ad%b8%e7%94%9f%e8%a1%a8%e8%81%af%e6%8e%a5%e7%8f%ad%e7%b4%9a%e8%a1%a8%ef%bc%88%e6%95%b8%e6%93%9a%e5%ba%ab%e5%ad%b8%e7%94%9f%e8%a1%a8%e9%80%a3-IzxIkMvNgX\">\u6578\u64da\u5eab\u64cd\u4f5c\u4e4b\u5b78\u751f\u8868\u806f\u63a5\u73ed\u7d1a\u8868\uff08\u6578\u64da\u5eab\u5b78\u751f\u8868\u9023\u73ed\u7d1a\u8868\uff09<\/h1>\n<p>\u5728\u73fe\u4ee3\u7684\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0c\u6578\u64da\u7684\u7d44\u7e54\u548c\u67e5\u8a62\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u7279\u5225\u662f\u5728\u6559\u80b2\u9818\u57df\uff0c\u5b78\u751f\u548c\u73ed\u7d1a\u4e4b\u9593\u7684\u95dc\u4fc2\u7d93\u5e38\u9700\u8981\u9032\u884c\u67e5\u8a62\u548c\u64cd\u4f5c\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u5728\u6578\u64da\u5eab\u4e2d\u9032\u884c\u5b78\u751f\u8868\u8207\u73ed\u7d1a\u8868\u7684\u806f\u63a5\u64cd\u4f5c\uff0c\u4e26\u63d0\u4f9b\u76f8\u95dc\u7684\u793a\u4f8b\u548c\u4ee3\u78bc\u3002<\/p>\n<h2 id=\"%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a8%ad%e8%a8%88%e6%a6%82%e8%bf%b0-IzxIkMvNgX\">\u6578\u64da\u5eab\u8a2d\u8a08\u6982\u8ff0<\/h2>\n<p>\u5728\u8a2d\u8a08\u6578\u64da\u5eab\u6642\uff0c\u901a\u5e38\u6703\u6709\u591a\u500b\u8868\u683c\u4f86\u5b58\u5132\u4e0d\u540c\u985e\u578b\u7684\u6578\u64da\u3002\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u5c07\u8003\u616e\u5169\u500b\u4e3b\u8981\u7684\u8868\u683c\uff1a\u5b78\u751f\u8868\uff08Students\uff09\u548c\u73ed\u7d1a\u8868\uff08Classes\uff09\u3002<\/p>\n<ul>\n<li><strong>\u5b78\u751f\u8868\uff08Students\uff09<\/strong>\n<ul>\n<li>student_id (\u5b78\u751fID)<\/li>\n<li>name (\u59d3\u540d)<\/li>\n<li>class_id (\u73ed\u7d1aID)<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u73ed\u7d1a\u8868\uff08Classes\uff09<\/strong>\n<ul>\n<li>class_id (\u73ed\u7d1aID)<\/li>\n<li>class_name (\u73ed\u7d1a\u540d\u7a31)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>\u5728\u9019\u500b\u8a2d\u8a08\u4e2d\uff0c\u5b78\u751f\u8868\u4e2d\u7684\u6bcf\u500b\u5b78\u751f\u90fd\u6703\u6709\u4e00\u500b\u5c0d\u61c9\u7684\u73ed\u7d1aID\uff0c\u9019\u6a23\u53ef\u4ee5\u5c07\u5b78\u751f\u8207\u5176\u6240\u5c6c\u7684\u73ed\u7d1a\u9032\u884c\u95dc\u806f\u3002<\/p>\n<h2 id=\"%e8%81%af%e6%8e%a5%e6%93%8d%e4%bd%9c%e7%9a%84%e5%bf%85%e8%a6%81%e6%80%a7-IzxIkMvNgX\">\u806f\u63a5\u64cd\u4f5c\u7684\u5fc5\u8981\u6027<\/h2>\n<p>\u7576\u6211\u5011\u9700\u8981\u67e5\u8a62\u5b78\u751f\u53ca\u5176\u6240\u5c6c\u73ed\u7d1a\u7684\u8a73\u7d30\u4fe1\u606f\u6642\uff0c\u55ae\u7368\u67e5\u8a62\u5b78\u751f\u8868\u6216\u73ed\u7d1a\u8868\u4e26\u4e0d\u80fd\u6eff\u8db3\u9700\u6c42\u3002\u9019\u6642\uff0c\u6211\u5011\u9700\u8981\u4f7f\u7528\u806f\u63a5\u64cd\u4f5c\u4f86\u5c07\u9019\u5169\u500b\u8868\u683c\u7684\u6578\u64da\u7d50\u5408\u8d77\u4f86\u3002<\/p>\n<h2 id=\"sql%e8%81%af%e6%8e%a5%e7%a4%ba%e4%be%8b-IzxIkMvNgX\">SQL\u806f\u63a5\u793a\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4f7f\u7528SQL\u8a9e\u8a00\u9032\u884c\u5b78\u751f\u8868\u8207\u73ed\u7d1a\u8868\u806f\u63a5\u7684\u57fa\u672c\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT Students.name, Classes.class_name\nFROM Students\nJOIN Classes ON Students.class_id = Classes.class_id;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c\u6211\u5011\u9078\u64c7\u4e86\u5b78\u751f\u7684\u59d3\u540d\u548c\u73ed\u7d1a\u540d\u7a31\u3002\u4f7f\u7528JOIN\u8a9e\u53e5\uff0c\u6211\u5011\u5c07\u5b78\u751f\u8868\u548c\u73ed\u7d1a\u8868\u6839\u64da\u73ed\u7d1aID\u9032\u884c\u806f\u63a5\u3002\u9019\u6a23\uff0c\u6211\u5011\u5c31\u80fd\u5920\u7372\u5f97\u6bcf\u4f4d\u5b78\u751f\u53ca\u5176\u6240\u5c6c\u73ed\u7d1a\u7684\u5b8c\u6574\u4fe1\u606f\u3002<\/p>\n<h2 id=\"%e4%b8%8d%e5%90%8c%e9%a1%9e%e5%9e%8b%e7%9a%84%e8%81%af%e6%8e%a5-IzxIkMvNgX\">\u4e0d\u540c\u985e\u578b\u7684\u806f\u63a5<\/h2>\n<p>\u5728SQL\u4e2d\uff0c\u6709\u591a\u7a2e\u4e0d\u540c\u985e\u578b\u7684\u806f\u63a5\u53ef\u4f9b\u9078\u64c7\uff0c\u6839\u64da\u9700\u6c42\u7684\u4e0d\u540c\uff0c\u53ef\u4ee5\u9078\u64c7\u9069\u5408\u7684\u806f\u63a5\u65b9\u5f0f\uff1a<\/p>\n<ul>\n<li><strong>INNER JOIN<\/strong>\uff1a\u53ea\u8fd4\u56de\u5169\u500b\u8868\u4e2d\u5339\u914d\u7684\u884c\u3002<\/li>\n<li><strong>LEFT JOIN<\/strong>\uff1a\u8fd4\u56de\u5de6\u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u5373\u4f7f\u53f3\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u884c\u3002<\/li>\n<li><strong>RIGHT JOIN<\/strong>\uff1a\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u5373\u4f7f\u5de6\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u884c\u3002<\/li>\n<li><strong>FULL OUTER JOIN<\/strong>\uff1a\u8fd4\u56de\u5169\u500b\u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u7121\u8ad6\u662f\u5426\u6709\u5339\u914d\u3002<\/li>\n<\/ul>\n<p>\u6839\u64da\u5177\u9ad4\u7684\u696d\u52d9\u9700\u6c42\uff0c\u9078\u64c7\u5408\u9069\u7684\u806f\u63a5\u985e\u578b\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8a62\u7684\u6548\u7387\u548c\u6e96\u78ba\u6027\u3002<\/p>\n<h2 id=\"%e6%80%a7%e8%83%bd%e8%80%83%e9%87%8f-IzxIkMvNgX\">\u6027\u80fd\u8003\u91cf<\/h2>\n<p>\u5728\u9032\u884c\u806f\u63a5\u64cd\u4f5c\u6642\uff0c\u6027\u80fd\u662f\u4e00\u500b\u91cd\u8981\u7684\u8003\u91cf\u56e0\u7d20\u3002\u96a8\u8457\u6578\u64da\u91cf\u7684\u589e\u52a0\uff0c\u806f\u63a5\u64cd\u4f5c\u53ef\u80fd\u6703\u8b8a\u5f97\u7de9\u6162\u3002\u56e0\u6b64\uff0c\u5c0d\u65bc\u5927\u578b\u6578\u64da\u96c6\uff0c\u61c9\u8003\u616e\u4ee5\u4e0b\u5e7e\u9ede\uff1a<\/p>\n<ul>\n<li>\u78ba\u4fdd\u5728\u806f\u63a5\u7684\u5b57\u6bb5\u4e0a\u5efa\u7acb\u7d22\u5f15\uff0c\u4ee5\u63d0\u9ad8\u67e5\u8a62\u901f\u5ea6\u3002<\/li>\n<li>\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u806f\u63a5\uff0c\u50c5\u67e5\u8a62\u6240\u9700\u7684\u6578\u64da\u3002<\/li>\n<li>\u5b9a\u671f\u9032\u884c\u6578\u64da\u5eab\u512a\u5316\uff0c\u4ee5\u4fdd\u6301\u6027\u80fd\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-IzxIkMvNgX\">\u7e3d\u7d50<\/h2>\n<p>\u5b78\u751f\u8868\u8207\u73ed\u7d1a\u8868\u7684\u806f\u63a5\u64cd\u4f5c\u662f\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\u4e00\u500b\u57fa\u672c\u800c\u91cd\u8981\u7684\u529f\u80fd\u3002\u901a\u904e\u5408\u7406\u7684\u6578\u64da\u5eab\u8a2d\u8a08\u548c\u6709\u6548\u7684SQL\u67e5\u8a62\uff0c\u6211\u5011\u53ef\u4ee5\u8f15\u9b06\u5730\u7372\u53d6\u6240\u9700\u7684\u4fe1\u606f\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u61c9\u7528\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\u81f3\u95dc\u91cd\u8981\u3002\u82e5\u60a8\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u6216\u5176\u4ed6\u76f8\u95dc\u6280\u8853\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\uff0c\u63a2\u7d22\u6211\u5011\u7684<a href=\"https:\/\/server.hk\">VPS<\/a> \u53ca\u5176\u4ed6\u670d\u52d9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22\u5982\u4f55\u5728\u6578\u64da\u5eab\u4e2d\u64cd\u4f5c\u5b78\u751f\u8868\u8207\u73ed\u7d1a\u8868\u7684\u806f\u63a5\uff0c\u63d0\u5347\u6578\u64da\u7ba1\u7406\u6548\u7387\u8207\u67e5\u8a62\u6027\u80fd\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-186218","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186218","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=186218"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186218\/revisions"}],"predecessor-version":[{"id":186219,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186218\/revisions\/186219"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=186218"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=186218"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=186218"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}