{"id":200422,"date":"2025-05-06T10:10:40","date_gmt":"2025-05-06T02:10:40","guid":{"rendered":"https:\/\/server.hk\/cnblog\/200422\/"},"modified":"2025-05-06T10:10:40","modified_gmt":"2025-05-06T02:10:40","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8-mysql-update-%e8%af%ad%e5%8f%a5%e4%b8%8e-left-join-%e8%8e%b7%e5%8f%96%e5%a4%9a%e6%9d%a1%e6%95%b0%e6%8d%ae%e4%b8%ad%e7%9a%84%e6%9c%80%e5%a4%a7%e5%80%bc%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/200422\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528 MySQL update \u8bed\u53e5\u4e0e left join \u83b7\u53d6\u591a\u6761\u6570\u636e\u4e2d\u7684\u6700\u5927\u503c\uff1f"},"content":{"rendered":"<p><b><\/b> <\/p>\n<h1>\u5982\u4f55\u4f7f\u7528 MySQL update \u8bed\u53e5\u4e0e left join \u83b7\u53d6\u591a\u6761\u6570\u636e\u4e2d\u7684\u6700\u5927\u503c\uff1f<\/h1>\n<p>\u6570\u636e\u5e93\u5c0f\u767d\u4e00\u679a\uff0c\u6b63\u5728\u4e0d\u65ad\u5b66\u4e60\u79ef\u7d2f\u77e5\u8bc6\uff0c\u73b0\u5c06\u5b66\u4e60\u5230\u7684\u77e5\u8bc6\u8bb0\u5f55\u4e00\u4e0b\uff0c\u4e5f\u662f\u5c06\u6211\u7684\u6240\u5f97\u5206\u4eab\u7ed9\u5927\u5bb6\uff01\u800c\u4eca\u5929\u8fd9\u7bc7\u6587\u7ae0\u300a\u5982\u4f55\u4f7f\u7528 MySQL update \u8bed\u53e5\u4e0e left join \u83b7\u53d6\u591a\u6761\u6570\u636e\u4e2d\u7684\u6700\u5927\u503c\uff1f\u300b\u5e26\u5927\u5bb6\u6765\u4e86\u89e3\u4e00\u4e0b##content_title##\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u7684\u77e5\u8bc6\u79ef\u7d2f\u6709\u6240\u5e2e\u52a9\uff0c\u4ece\u800c\u5f25\u8865\u81ea\u5df1\u7684\u4e0d\u8db3\uff0c\u52a9\u529b\u5b9e\u6218\u5f00\u53d1\uff01<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20241104\/17307259576728c845b47d2.jpg\" class=\"aligncenter\"><\/p>\n<p><strong>mysql \u6570\u636e\u5e93\u4e2d update \u8bed\u53e5 left join \u83b7\u53d6\u591a\u6761\u6570\u636e\u4e2d\u6700\u5927\u503c<\/strong><\/p>\n<p>mysql \u4e2d\u7684 update \u8bed\u53e5\u53ef\u4ee5\u7528\u4e8e\u66f4\u65b0\u8868\u4e2d\u7684\u6570\u636e\u3002\u5982\u679c\u9700\u8981\u66f4\u65b0\u67d0\u4e00\u5b57\u6bb5\u7684\u503c\u4e3a\u5176\u4ed6\u8868\u4e2d\u591a\u6761\u6570\u636e\u4e2d\u67d0\u5b57\u6bb5\u7684\u6700\u5927\u503c\uff0c\u53ef\u4ee5\u4f7f\u7528 left join \u6765\u5b9e\u73b0\u3002<\/p>\n<p><strong>\u95ee\u9898\u80cc\u666f<\/strong><\/p>\n<p>\u6211\u4eec\u6709\u4e00\u5f20 student \u8868\uff0c\u5176\u4e2d\u5305\u542b\u5b66\u751f\u59d3\u540d name \u548c\u5206\u6570 score \u5b57\u6bb5\u3002\u8fd8\u6709\u4e00\u5f20 score \u8868\uff0c\u5176\u4e2d\u5305\u542b\u5b66\u751f\u7684\u5206\u6570\u8bb0\u5f55\uff0c\u6bcf\u4e2a\u5b66\u751f\u53ef\u80fd\u6709\u591a\u6b21\u5206\u6570\u8bb0\u5f55\u3002<\/p>\n<p><strong>\u66f4\u65b0\u8bed\u53e5<\/strong><\/p>\n<p>\u8981\u5c06 student \u8868\u4e2d score \u5b57\u6bb5\u66f4\u65b0\u4e3a score \u8868\u4e2d\u6bcf\u4e2a\u5b66\u751f\u7684\u6700\u9ad8\u5206\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b update \u8bed\u53e5\uff1a<\/p>\n<pre>update student set score = (select max(score) from score where score.student_id = student.id)<\/pre>\n<p><strong>left join \u7528\u6cd5<\/strong><\/p>\n<p>left join \u8bed\u6cd5\u5c06 student \u8868\u4e0e score \u8868\u8fde\u63a5\uff0c\u5e76\u8fd4\u56de student \u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u5373\u4f7f\u8fd9\u4e9b\u884c\u5728 score \u8868\u4e2d\u6ca1\u6709\u5339\u914d\u9879\u3002\u5982\u679c student \u8868\u4e2d\u7684\u67d0\u4e00\u884c\u5728 score \u8868\u4e2d\u6709\u591a\u6761\u5339\u914d\u9879\uff0c\u5219 left join \u5c06\u8fd4\u56de\u5176\u4e2d\u5305\u542b\u6700\u5927\u5206\u6570\u7684\u90a3\u6761\u8bb0\u5f55\u3002<\/p>\n<p><strong>\u67e5\u8be2\u793a\u4f8b<\/strong><\/p>\n<p>\u66f4\u65b0\u540e\u7684 student \u8868\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n<table>\n<thead>\n<tr>\n<th>id<\/th>\n<th>name<\/th>\n<th>score<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1<\/td>\n<td>\u5c0f\u660e<\/td>\n<td>80<\/td>\n<\/tr>\n<tr>\n<td>2<\/td>\n<td>\u5c0f\u7ea2<\/td>\n<td>98<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u7406\u8bba\u8981\u638c\u63e1\uff0c\u5b9e\u64cd\u4e0d\u80fd\u843d\uff01\u4ee5\u4e0a\u5173\u4e8e\u300a\u5982\u4f55\u4f7f\u7528 MySQL update \u8bed\u53e5\u4e0e left join \u83b7\u53d6\u591a\u6761\u6570\u636e\u4e2d\u7684\u6700\u5927\u503c\uff1f\u300b\u7684\u8be6\u7ec6\u4ecb\u7ecd\uff0c\u5927\u5bb6\u90fd\u638c\u63e1\u4e86\u5427\uff01\u5982\u679c\u60f3\u8981\u7ee7\u7eed\u63d0\u5347\u81ea\u5df1\u7684\u80fd\u529b\uff0c\u90a3\u4e48\u5c31\u6765\u5173\u6ce8\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\u5427\uff01<\/p>\n<dl>\n<dt>\n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"<p>\u5982\u4f55\u4f7f\u7528 MySQL updat&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-200422","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200422","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"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=200422"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200422\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=200422"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=200422"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=200422"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}