{"id":76254,"date":"2024-10-16T05:08:14","date_gmt":"2024-10-15T21:08:14","guid":{"rendered":"https:\/\/server.hk\/cnblog\/76254\/"},"modified":"2024-10-16T05:08:14","modified_gmt":"2024-10-15T21:08:14","slug":"mysql%e5%85%a5%e9%96%80%ef%bc%9a%e4%bd%bf%e7%94%a8right-join%e9%97%9c%e9%8d%b5%e5%ad%97%e8%bf%94%e5%9b%9e%e5%8f%b3%e8%a1%a8%e4%b8%ad%e7%9a%84%e6%89%80%e6%9c%89%e8%a8%98%e9%8c%84%e5%92%8c%e5%b7%a6","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/76254\/","title":{"rendered":"MySQL\u5165\u9580\uff1a\u4f7f\u7528RIGHT JOIN\u95dc\u9375\u5b57\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u548c\u5de6\u8868\u4e2d\u5339\u914d\u7684\u8a18\u9304\u3002"},"content":{"rendered":"<h1 id=\"mysql%e5%85%a5%e9%96%80%ef%bc%9a%e4%bd%bf%e7%94%a8right-join%e9%97%9c%e9%8d%b5%e5%ad%97%e8%bf%94%e5%9b%9e%e5%8f%b3%e8%a1%a8%e4%b8%ad%e7%9a%84%e6%89%80%e6%9c%89%e8%a8%98%e9%8c%84%e5%92%8c%e5%b7%a6-FFtEGpVHfV\">MySQL\u5165\u9580\uff1a\u4f7f\u7528RIGHT JOIN\u95dc\u9375\u5b57\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u548c\u5de6\u8868\u4e2d\u5339\u914d\u7684\u8a18\u9304<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u975e\u5e38\u6d41\u884c\u7684\u9078\u64c7\uff0c\u56e0\u70ba\u5b83\u7684\u9748\u6d3b\u6027\u548c\u5f37\u5927\u7684\u529f\u80fd\u3002\u7576\u6211\u5011\u9700\u8981\u5f9e\u591a\u500b\u8868\u4e2d\u63d0\u53d6\u6578\u64da\u6642\uff0cJOIN\u64cd\u4f5c\u662f\u5fc5\u4e0d\u53ef\u5c11\u7684\u3002\u672c\u6587\u5c07\u91cd\u9ede\u4ecb\u7d39RIGHT JOIN\u95dc\u9375\u5b57\uff0c\u4e26\u89e3\u91cb\u5982\u4f55\u4f7f\u7528\u5b83\u4f86\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u4ee5\u53ca\u5de6\u8868\u4e2d\u5339\u914d\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%afjoin%ef%bc%9f-FFtEGpVHfV\">\u4ec0\u9ebc\u662fJOIN\uff1f<\/h2>\n<p>JOIN\u662f\u4e00\u7a2eSQL\u64cd\u4f5c\uff0c\u7528\u65bc\u5c07\u5169\u500b\u6216\u591a\u500b\u8868\u4e2d\u7684\u6578\u64da\u6839\u64da\u67d0\u4e9b\u689d\u4ef6\u9032\u884c\u7d44\u5408\u3002\u6839\u64da\u4e0d\u540c\u7684\u9700\u6c42\uff0cJOIN\u6709\u591a\u7a2e\u985e\u578b\uff0c\u5305\u62ecINNER JOIN\u3001LEFT JOIN\u3001RIGHT JOIN\u548cFULL JOIN\u7b49\u3002\u6bcf\u7a2eJOIN\u7684\u884c\u70ba\u548c\u8fd4\u56de\u7684\u7d50\u679c\u96c6\u90fd\u6709\u6240\u4e0d\u540c\u3002<\/p>\n<h2 id=\"right-join%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-FFtEGpVHfV\">RIGHT JOIN\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>RIGHT JOIN\uff08\u6216\u7a31\u70baRIGHT OUTER JOIN\uff09\u662f\u4e00\u7a2e\u7279\u6b8a\u7684JOIN\u64cd\u4f5c\uff0c\u5b83\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff0c\u5373\u4f7f\u5728\u5de6\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u8a18\u9304\u3002\u7576\u5de6\u8868\u4e2d\u6c92\u6709\u8207\u53f3\u8868\u7684\u8a18\u9304\u5339\u914d\u6642\uff0c\u7d50\u679c\u96c6\u4e2d\u7684\u76f8\u61c9\u5217\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"right-join%e7%9a%84%e8%aa%9e%e6%b3%95-FFtEGpVHfV\">RIGHT JOIN\u7684\u8a9e\u6cd5<\/h2>\n<pre><code>\nSELECT \u5217\u540d1, \u5217\u540d2, ...\nFROM \u88681\nRIGHT JOIN \u88682\nON \u88681.\u5217\u540d = \u88682.\u5217\u540d;\n<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c\u88681\u662f\u5de6\u8868\uff0c\u88682\u662f\u53f3\u8868\u3002ON\u5b50\u53e5\u7528\u65bc\u6307\u5b9aJOIN\u7684\u689d\u4ef6\u3002<\/p>\n<h2 id=\"right-join%e7%9a%84%e5%af%a6%e9%9a%9b%e7%a4%ba%e4%be%8b-FFtEGpVHfV\">RIGHT JOIN\u7684\u5be6\u969b\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    +----+----------+\n    | id | name     |\n    +----+----------+\n    | 1  | Alice    |\n    | 2  | Bob      |\n    | 3  | Charlie  |\n    +----+----------+\n    <\/code><\/pre>\n<li><strong>orders<\/strong>\u8868\uff1a<\/li>\n<pre><code>\n    +----+------------+\n    | id | customer_id|\n    +----+------------+\n    | 1  | 1          |\n    | 2  | 1          |\n    | 3  | 2          |\n    | 4  | 4          |\n    +----+------------+\n    <\/code><\/pre>\n<\/ul>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c<strong>customers<\/strong>\u8868\u5305\u542b\u5ba2\u6236\u7684\u57fa\u672c\u4fe1\u606f\uff0c\u800c<strong>orders<\/strong>\u8868\u5247\u8a18\u9304\u4e86\u6bcf\u500b\u5ba2\u6236\u7684\u8a02\u55ae\u3002\u6ce8\u610f\uff0c<strong>orders<\/strong>\u8868\u4e2d\u6709\u4e00\u500bcustomer_id\u70ba4\u7684\u8a02\u55ae\uff0c\u4f46\u5728<strong>customers<\/strong>\u8868\u4e2d\u4e26\u4e0d\u5b58\u5728\u5c0d\u61c9\u7684\u5ba2\u6236\u3002<\/p>\n<p>\u5982\u679c\u6211\u5011\u60f3\u8981\u67e5\u8a62\u6240\u6709\u8a02\u55ae\u53ca\u5176\u5c0d\u61c9\u7684\u5ba2\u6236\u540d\u7a31\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bSQL\u8a9e\u53e5\uff1a<\/p>\n<pre><code>\nSELECT customers.name, orders.id\nFROM customers\nRIGHT JOIN orders\nON customers.id = orders.customer_id;\n<\/code><\/pre>\n<p>\u57f7\u884c\u9019\u500b\u67e5\u8a62\u5f8c\uff0c\u6211\u5011\u5c07\u5f97\u5230\u4ee5\u4e0b\u7d50\u679c\uff1a<\/p>\n<pre><code>\n+----------+----+\n| name     | id |\n+----------+----+\n| Alice    | 1  |\n| Alice    | 2  |\n| Bob      | 3  |\n| NULL     | 4  |\n+----------+----+\n<\/code><\/pre>\n<p>\u5f9e\u7d50\u679c\u4e2d\u53ef\u4ee5\u770b\u51fa\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\uff0c\u6240\u4ee5\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8right-join%e7%9a%84%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-FFtEGpVHfV\">\u4f7f\u7528RIGHT JOIN\u7684\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li>RIGHT JOIN\u901a\u5e38\u7528\u65bc\u9700\u8981\u4fdd\u7559\u53f3\u8868\u4e2d\u6240\u6709\u8a18\u9304\u7684\u60c5\u6cc1\u3002<\/li>\n<li>\u5728\u4f7f\u7528RIGHT JOIN\u6642\uff0c\u78ba\u4fdd\u7406\u89e3\u6578\u64da\u7684\u95dc\u806f\u6027\uff0c\u4ee5\u907f\u514d\u4e0d\u5fc5\u8981\u7684NULL\u503c\u3002<\/li>\n<li>\u5728\u5927\u578b\u6578\u64da\u96c6\u4e0a\u4f7f\u7528RIGHT JOIN\u53ef\u80fd\u6703\u5f71\u97ff\u67e5\u8a62\u6027\u80fd\uff0c\u56e0\u6b64\u61c9\u8b39\u614e\u4f7f\u7528\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-FFtEGpVHfV\">\u7e3d\u7d50<\/h2>\n<p>RIGHT JOIN\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u53ef\u4ee5\u5e6b\u52a9\u6211\u5011\u5f9e\u591a\u500b\u8868\u4e2d\u63d0\u53d6\u6240\u9700\u7684\u6578\u64da\u3002\u901a\u904e\u7406\u89e3\u5176\u8a9e\u6cd5\u548c\u4f7f\u7528\u5834\u666f\uff0c\u6211\u5011\u53ef\u4ee5\u66f4\u6709\u6548\u5730\u9032\u884c\u6578\u64da\u67e5\u8a62\u548c\u5206\u6790\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u7528\u6236\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\u81f3\u95dc\u91cd\u8981\u3002\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u53ef\u9760\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u670d\u52d9\uff0cServer.HK\u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u60a8\u7684\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2MySQL\u5165\u9580\uff0c\u638c\u63e1\u4f7f\u7528RIGHT JOIN\u95dc\u9375\u5b57\uff0c\u8fd4\u56de\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u53ca\u5de6\u8868\u4e2d\u5339\u914d\u7684\u8a18\u9304\uff0c\u63d0\u5347\u6578\u64da\u67e5\u8a62\u6280\u5de7\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-76254","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76254","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=76254"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76254\/revisions"}],"predecessor-version":[{"id":76255,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76254\/revisions\/76255"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=76254"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=76254"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=76254"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}