{"id":79562,"date":"2024-10-16T13:19:14","date_gmt":"2024-10-16T05:19:14","guid":{"rendered":"https:\/\/server.hk\/cnblog\/79562\/"},"modified":"2024-10-16T13:19:15","modified_gmt":"2024-10-16T05:19:15","slug":"mysql%e6%8c%87%e4%bb%a4-right-join%ef%bc%88%e5%8f%b3%e9%80%a3%e6%8e%a5%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/79562\/","title":{"rendered":"MySQL\u6307\u4ee4: RIGHT JOIN\uff08\u53f3\u9023\u63a5\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-right-join%ef%bc%88%e5%8f%b3%e9%80%a3%e6%8e%a5%ef%bc%89-TZWZbKPCne\">MySQL\u6307\u4ee4: RIGHT JOIN\uff08\u53f3\u9023\u63a5\uff09<\/h1>\n<p>\u5728\u95dc\u806f\u5f0f\u8cc7\u6599\u5eab\u4e2d\uff0cJOIN\u64cd\u4f5c\u662f\u7528\u4f86\u5f9e\u5169\u500b\u6216\u591a\u500b\u8868\u4e2d\u67e5\u8a62\u8cc7\u6599\u7684\u95dc\u9375\u5de5\u5177\u3002MySQL\u63d0\u4f9b\u4e86\u591a\u7a2eJOIN\u985e\u578b\uff0c\u5176\u4e2d\u4e4b\u4e00\u5c31\u662fRIGHT JOIN\uff08\u53f3\u9023\u63a5\uff09\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eRIGHT JOIN\u7684\u6982\u5ff5\u3001\u7528\u6cd5\u53ca\u5176\u5728\u5be6\u969b\u61c9\u7528\u4e2d\u7684\u793a\u4f8b\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%afright-join%ef%bc%9f-TZWZbKPCne\">\u4ec0\u9ebc\u662fRIGHT JOIN\uff1f<\/h2>\n<p>RIGHT JOIN\u662f\u4e00\u7a2e\u9023\u63a5\u64cd\u4f5c\uff0c\u4e3b\u8981\u7528\u65bc\u5f9e\u53f3\u5074\u8868\u4e2d\u9078\u53d6\u6240\u6709\u7684\u8a18\u9304\uff0c\u4e26\u4e14\u6839\u64da\u5de6\u5074\u8868\u7684\u5339\u914d\u689d\u4ef6\u4f86\u9078\u53d6\u76f8\u61c9\u7684\u8a18\u9304\u3002\u5982\u679c\u5de6\u5074\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u8a18\u9304\uff0c\u5247\u7d50\u679c\u4e2d\u4ecd\u6703\u986f\u793a\u53f3\u5074\u8868\u7684\u8a18\u9304\uff0c\u4e26\u4e14\u5de6\u5074\u8868\u7684\u76f8\u61c9\u6b04\u4f4d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"right-join%e7%9a%84%e8%aa%9e%e6%b3%95-TZWZbKPCne\">RIGHT JOIN\u7684\u8a9e\u6cd5<\/h2>\n<p>RIGHT JOIN\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT \u5217\u540d1, \u5217\u540d2, ...\nFROM \u5de6\u5074\u8868\nRIGHT JOIN \u53f3\u5074\u8868\nON \u5de6\u5074\u8868.\u6b04\u4f4d = \u53f3\u5074\u8868.\u6b04\u4f4d;<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c\u60a8\u9700\u8981\u66ff\u63db\u201c\u5217\u540d1, \u5217\u540d2, &#8230;\u201d\u70ba\u60a8\u60f3\u8981\u67e5\u8a62\u7684\u5177\u9ad4\u6b04\u4f4d\uff0c\u4e26\u4e14\u6307\u5b9a\u5de6\u5074\u8868\u548c\u53f3\u5074\u8868\u7684\u540d\u7a31\u4ee5\u53ca\u5b83\u5011\u4e4b\u9593\u7684\u5339\u914d\u689d\u4ef6\u3002<\/p>\n<h2 id=\"right-join%e7%9a%84%e7%a4%ba%e4%be%8b-TZWZbKPCne\">RIGHT JOIN\u7684\u793a\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8868\uff1a<strong>customers<\/strong>\uff08\u5ba2\u6236\uff09\u548c<strong>orders<\/strong>\uff08\u8a02\u55ae\uff09\u3002<\/p>\n<ul>\n<li><strong>customers<\/strong>\u8868\uff1a<\/li>\n<pre><code>+----+----------+\n| id | name     |\n+----+----------+\n| 1  | Alice    |\n| 2  | Bob      |\n| 3  | Charlie   |\n+----+----------+<\/code><\/pre>\n<li><strong>orders<\/strong>\u8868\uff1a<\/li>\n<pre><code>+----+------------+\n| id | customer_id|\n+----+------------+\n| 1  | 1          |\n| 2  | 1          |\n| 3  | 2          |\n| 4  | 4          |\n+----+------------+<\/code><\/pre>\n<\/ul>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c<strong>customers<\/strong>\u8868\u5305\u542b\u4e09\u500b\u5ba2\u6236\uff0c\u800c<strong>orders<\/strong>\u8868\u5247\u5305\u542b\u56db\u500b\u8a02\u55ae\uff0c\u5176\u4e2d\u4e00\u500b\u8a02\u55ae\u7684customer_id\uff08\u5ba2\u6236ID\uff09\u70ba4\uff0c\u9019\u5728<strong>customers<\/strong>\u8868\u4e2d\u4e26\u4e0d\u5b58\u5728\u3002<\/p>\n<p>\u5982\u679c\u6211\u5011\u4f7f\u7528RIGHT JOIN\u4f86\u67e5\u8a62\u6240\u6709\u8a02\u55ae\u53ca\u5176\u5c0d\u61c9\u7684\u5ba2\u6236\uff0c\u8a9e\u53e5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT customers.name, orders.id\nFROM customers\nRIGHT JOIN orders\nON customers.id = orders.customer_id;<\/code><\/pre>\n<p>\u57f7\u884c\u9019\u500b\u67e5\u8a62\u5f8c\uff0c\u7d50\u679c\u5c07\u6703\u662f\uff1a<\/p>\n<pre><code>+----------+----+\n| name     | id |\n+----------+----+\n| Alice    | 1  |\n| Alice    | 2  |\n| Bob      | 3  |\n| NULL     | 4  |\n+----------+----+<\/code><\/pre>\n<p>\u5f9e\u7d50\u679c\u4e2d\u53ef\u4ee5\u770b\u5230\uff0c\u6240\u6709\u7684\u8a02\u55ae\u90fd\u88ab\u5217\u51fa\u4f86\u4e86\uff0c\u5373\u4f7f\u5c0d\u65bccustomer_id\u70ba4\u7684\u8a02\u55ae\uff0c\u56e0\u70ba\u5728<strong>customers<\/strong>\u8868\u4e2d\u627e\u4e0d\u5230\u5c0d\u61c9\u7684\u5ba2\u6236\uff0cname\u6b04\u4f4d\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"right-join%e7%9a%84%e6%87%89%e7%94%a8%e5%a0%b4%e6%99%af-TZWZbKPCne\">RIGHT JOIN\u7684\u61c9\u7528\u5834\u666f<\/h2>\n<p>RIGHT JOIN\u901a\u5e38\u7528\u65bc\u4ee5\u4e0b\u5e7e\u7a2e\u60c5\u6cc1\uff1a<\/p>\n<ul>\n<li>\u9700\u8981\u5f9e\u53f3\u5074\u8868\u4e2d\u7372\u53d6\u6240\u6709\u8a18\u9304\uff0c\u800c\u4e0d\u5728\u4e4e\u5de6\u5074\u8868\u7684\u5339\u914d\u60c5\u6cc1\u3002<\/li>\n<li>\u5728\u6578\u64da\u5206\u6790\u4e2d\uff0c\u7576\u9700\u8981\u78ba\u4fdd\u67d0\u4e9b\u8cc7\u6599\u7684\u5b8c\u6574\u6027\u6642\uff0cRIGHT JOIN\u53ef\u4ee5\u5e6b\u52a9\u8b58\u5225\u7f3a\u5931\u7684\u95dc\u806f\u3002<\/li>\n<li>\u5728\u5831\u544a\u751f\u6210\u4e2d\uff0cRIGHT JOIN\u53ef\u4ee5\u7528\u4f86\u986f\u793a\u6240\u6709\u76f8\u95dc\u7684\u6578\u64da\uff0c\u5373\u4f7f\u67d0\u4e9b\u6578\u64da\u5728\u5de6\u5074\u8868\u4e2d\u4e0d\u5b58\u5728\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-TZWZbKPCne\">\u7e3d\u7d50<\/h2>\n<p>RIGHT JOIN\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u80fd\u5920\u5e6b\u52a9\u958b\u767c\u8005\u5728\u67e5\u8a62\u8cc7\u6599\u6642\u7372\u53d6\u66f4\u5168\u9762\u7684\u8cc7\u8a0a\u3002\u900f\u904eRIGHT JOIN\uff0c\u6211\u5011\u53ef\u4ee5\u78ba\u4fdd\u5f9e\u53f3\u5074\u8868\u4e2d\u7372\u53d6\u6240\u6709\u7684\u8a18\u9304\uff0c\u4e26\u4e14\u80fd\u5920\u6e05\u695a\u5730\u8b58\u5225\u51fa\u54ea\u4e9b\u8cc7\u6599\u5728\u5de6\u5074\u8868\u4e2d\u7f3a\u5931\u3002\u5c0d\u65bc\u9700\u8981\u9032\u884c\u8907\u96dc\u67e5\u8a62\u7684\u958b\u767c\u8005\u4f86\u8aaa\uff0c\u638c\u63e1RIGHT JOIN\u7684\u7528\u6cd5\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK\u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u9069\u5408\u5404\u7a2e\u9700\u6c42\u3002\u7121\u8ad6\u662f <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u9084\u662f\u5176\u4ed6\u985e\u578b\u7684 <a href=\"https:\/\/server.hk\">\u4f3a\u670d\u5668<\/a>\uff0c\u6211\u5011\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u670d\u52d9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u4e2d\u7684RIGHT JOIN\uff08\u53f3\u9023\u63a5\uff09\u6307\u4ee4\uff0c\u5b78\u7fd2\u5982\u4f55\u5f9e\u53f3\u8868\u4e2d\u7372\u53d6\u6240\u6709\u8a18\u9304\u4e26\u5339\u914d\u5de6\u8868\u7684\u6578\u64da\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-79562","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/79562","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=79562"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/79562\/revisions"}],"predecessor-version":[{"id":79563,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/79562\/revisions\/79563"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=79562"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=79562"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=79562"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}