{"id":78558,"date":"2024-10-16T12:02:17","date_gmt":"2024-10-16T04:02:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/78558\/"},"modified":"2024-10-16T12:02:17","modified_gmt":"2024-10-16T04:02:17","slug":"mysql%e6%8c%87%e4%bb%a4-full-join%ef%bc%88%e5%85%a8%e9%80%a3%e6%8e%a5%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/78558\/","title":{"rendered":"MySQL\u6307\u4ee4: FULL JOIN\uff08\u5168\u9023\u63a5\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-full-join%ef%bc%88%e5%85%a8%e9%80%a3%e6%8e%a5%ef%bc%89-mJhvIAGAkt\">MySQL\u6307\u4ee4: FULL JOIN\uff08\u5168\u9023\u63a5\uff09<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cJOIN\u64cd\u4f5c\u662f\u7528\u4f86\u7d50\u5408\u4f86\u81ea\u5169\u500b\u6216\u591a\u500b\u8868\u683c\u7684\u8cc7\u6599\u3002MySQL\u63d0\u4f9b\u4e86\u591a\u7a2eJOIN\u985e\u578b\uff0c\u5176\u4e2dFULL JOIN\uff08\u5168\u9023\u63a5\uff09\u662f\u4e00\u500b\u91cd\u8981\u7684\u6982\u5ff5\u3002\u96d6\u7136MySQL\u672c\u8eab\u4e0d\u76f4\u63a5\u652f\u6301FULL JOIN\uff0c\u4f46\u6211\u5011\u53ef\u4ee5\u901a\u904e\u7d50\u5408LEFT JOIN\u548cRIGHT JOIN\u4f86\u5be6\u73fe\u76f8\u540c\u7684\u6548\u679c\u3002<\/p>\n<h2 id=\"full-join%e7%9a%84%e6%a6%82%e5%bf%b5-mJhvIAGAkt\">FULL JOIN\u7684\u6982\u5ff5<\/h2>\n<p>FULL JOIN\u662f\u6307\u5f9e\u5169\u500b\u8868\u683c\u4e2d\u9078\u53d6\u6240\u6709\u7684\u8a18\u9304\uff0c\u7121\u8ad6\u5b83\u5011\u662f\u5426\u5339\u914d\u3002\u9019\u610f\u5473\u8457\uff0c\u5982\u679c\u67d0\u4e00\u8868\u683c\u4e2d\u7684\u8a18\u9304\u5728\u53e6\u4e00\u8868\u683c\u4e2d\u6c92\u6709\u5c0d\u61c9\u7684\u8a18\u9304\uff0c\u8a72\u8a18\u9304\u4ecd\u7136\u6703\u88ab\u5305\u542b\u5728\u7d50\u679c\u4e2d\uff0c\u4e26\u4e14\u5c0d\u61c9\u7684\u6b04\u4f4d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"full-join%e7%9a%84%e8%aa%9e%e6%b3%95-mJhvIAGAkt\">FULL JOIN\u7684\u8a9e\u6cd5<\/h2>\n<p>\u7531\u65bcMySQL\u4e0d\u652f\u6301FULL JOIN\uff0c\u6211\u5011\u53ef\u4ee5\u4f7f\u7528UNION\u4f86\u6a21\u64ec\u9019\u4e00\u64cd\u4f5c\u3002\u4ee5\u4e0b\u662f\u5be6\u73feFULL JOIN\u7684\u57fa\u672c\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>\nSELECT A.*, B.*\nFROM TableA A\nLEFT JOIN TableB B ON A.id = B.id\n\nUNION\n\nSELECT A.*, B.*\nFROM TableA A\nRIGHT JOIN TableB B ON A.id = B.id;\n<\/code><\/pre>\n<h2 id=\"%e7%af%84%e4%be%8b-mJhvIAGAkt\">\u7bc4\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8868\u683c\uff0c\u5206\u5225\u662f<code>employees<\/code>\u548c<code>departments<\/code>\u3002<code>employees<\/code>\u8868\u683c\u5305\u542b\u54e1\u5de5\u7684\u8cc7\u8a0a\uff0c\u800c<code>departments<\/code>\u8868\u683c\u5247\u5305\u542b\u90e8\u9580\u7684\u8cc7\u8a0a\u3002\u4ee5\u4e0b\u662f\u9019\u5169\u500b\u8868\u683c\u7684\u7d50\u69cb\uff1a<\/p>\n<ul>\n<li><code>employees<\/code>\u8868\u683c\uff1a<\/li>\n<ul>\n<li><code>id<\/code> (\u54e1\u5de5ID)<\/li>\n<li><code>name<\/code> (\u54e1\u5de5\u59d3\u540d)<\/li>\n<li><code>department_id<\/code> (\u90e8\u9580ID)<\/li>\n<\/ul>\n<li><code>departments<\/code>\u8868\u683c\uff1a<\/li>\n<ul>\n<li><code>id<\/code> (\u90e8\u9580ID)<\/li>\n<li><code>department_name<\/code> (\u90e8\u9580\u540d\u7a31)<\/li>\n<\/ul>\n<\/ul>\n<p>\u5047\u8a2d<code>employees<\/code>\u8868\u683c\u7684\u8cc7\u6599\u5982\u4e0b\uff1a<\/p>\n<pre><code>\nid | name      | department_id\n---|-----------|---------------\n1  | Alice     | 1\n2  | Bob       | 2\n3  | Charlie   | NULL\n<\/code><\/pre>\n<p>\u800c<code>departments<\/code>\u8868\u683c\u7684\u8cc7\u6599\u5982\u4e0b\uff1a<\/p>\n<pre><code>\nid | department_name\n---|-----------------\n1  | HR\n2  | IT\n3  | Marketing\n<\/code><\/pre>\n<p>\u4f7f\u7528FULL JOIN\u7684\u67e5\u8a62\u8a9e\u53e5\u5982\u4e0b\uff1a<\/p>\n<pre><code>\nSELECT A.*, B.*\nFROM employees A\nLEFT JOIN departments B ON A.department_id = B.id\n\nUNION\n\nSELECT A.*, B.*\nFROM employees A\nRIGHT JOIN departments B ON A.department_id = B.id;\n<\/code><\/pre>\n<p>\u57f7\u884c\u4e0a\u8ff0\u67e5\u8a62\u5f8c\uff0c\u7d50\u679c\u5c07\u6703\u662f\uff1a<\/p>\n<pre><code>\nid | name      | department_id | department_name\n---|-----------|---------------|-----------------\n1  | Alice     | 1             | HR\n2  | Bob       | 2             | IT\n3  | Charlie   | NULL          | NULL\nNULL | NULL    | NULL          | Marketing\n<\/code><\/pre>\n<p>\u5f9e\u7d50\u679c\u4e2d\u53ef\u4ee5\u770b\u5230\uff0c\u6240\u6709\u7684\u54e1\u5de5\u548c\u90e8\u9580\u90fd\u88ab\u5217\u51fa\u4f86\u4e86\uff0c\u5373\u4f7f\u67d0\u4e9b\u54e1\u5de5\u6c92\u6709\u5c0d\u61c9\u7684\u90e8\u9580\uff0c\u6216\u67d0\u4e9b\u90e8\u9580\u6c92\u6709\u5c0d\u61c9\u7684\u54e1\u5de5\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-mJhvIAGAkt\">\u7e3d\u7d50<\/h2>\n<p>FULL JOIN\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u53ef\u4ee5\u5e6b\u52a9\u6211\u5011\u5f9e\u591a\u500b\u8868\u683c\u4e2d\u7372\u53d6\u5b8c\u6574\u7684\u8cc7\u6599\u96c6\u3002\u96d6\u7136MySQL\u4e0d\u76f4\u63a5\u652f\u6301FULL JOIN\uff0c\u4f46\u901a\u904e\u7d50\u5408LEFT JOIN\u548cRIGHT JOIN\uff0c\u6211\u5011\u4ecd\u7136\u53ef\u4ee5\u5be6\u73fe\u76f8\u540c\u7684\u6548\u679c\u3002\u9019\u7a2e\u65b9\u6cd5\u5728\u8655\u7406\u8907\u96dc\u7684\u8cc7\u6599\u95dc\u4fc2\u6642\u7279\u5225\u6709\u7528\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc\u8cc7\u6599\u5eab\u7ba1\u7406\u6216\u5176\u4ed6\u6280\u8853\u554f\u984c\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\uff0c\u7279\u5225\u662f\u6211\u5011\u7684<a href=\"https:\/\/server.hk\">VPS<\/a> \u65b9\u6848\uff0c\u63d0\u4f9b\u7a69\u5b9a\u7684\u670d\u52d9\u548c\u9748\u6d3b\u7684\u9078\u64c7\uff0c\u9069\u5408\u5404\u7a2e\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u4e2d\u7684FULL JOIN\uff08\u5168\u8fde\u63a5\uff09\u6307\u4ee4\uff0c\u638c\u63e1\u5982\u4f55\u5408\u5e76\u4e24\u4e2a\u8868\u7684\u6240\u6709\u8bb0\u5f55\uff0c\u5305\u62ec\u5339\u914d\u548c\u4e0d\u5339\u914d\u7684\u884c\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-78558","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78558","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=78558"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78558\/revisions"}],"predecessor-version":[{"id":78559,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78558\/revisions\/78559"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=78558"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=78558"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=78558"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}