{"id":200425,"date":"2025-05-06T08:23:02","date_gmt":"2025-05-06T00:23:02","guid":{"rendered":"https:\/\/server.hk\/cnblog\/200425\/"},"modified":"2025-05-06T08:23:02","modified_gmt":"2025-05-06T00:23:02","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8-left-join-%e6%9b%b4%e6%96%b0-student-%e8%a1%a8%e4%b8%ad-score-%e5%ad%97%e6%ae%b5%e4%b8%ba%e5%af%b9%e5%ba%94-score-%e8%a1%a8%e4%b8%ad%e6%9c%80%e5%a4%a7%e5%80%bc","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/200425\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528 left join \u66f4\u65b0 student \u8868\u4e2d score \u5b57\u6bb5\u4e3a\u5bf9\u5e94 score \u8868\u4e2d\u6700\u5927\u503c\uff1f"},"content":{"rendered":"<p><b><\/b> <\/p>\n<h1>\u5982\u4f55\u4f7f\u7528 left join \u66f4\u65b0 student \u8868\u4e2d score \u5b57\u6bb5\u4e3a\u5bf9\u5e94 score 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join\u66f4\u65b0\u8868\u4e2d\u591a\u6761\u6570\u636e\u4e2d\u7684\u6700\u5927\u503c<\/strong><\/p>\n<p><strong>\u95ee\u9898\uff1a<\/strong><\/p>\n<p>\u5982\u4f55\u5c06student\u8868\u4e2dscore\u5b57\u6bb5\u66f4\u65b0\u4e3a\u5bf9\u5e94score\u8868\u4e2d\u6700\u5927\u503c\u7684score\uff1f<\/p>\n<p><strong>\u6570\u636e\u7ed3\u6784\uff1a<\/strong><\/p>\n<ul>\n<li>student\u8868\uff1aid\u3001name\u3001score<\/li>\n<li>score\u8868\uff1aid\u3001student_id\u3001score<\/li>\n<\/ul>\n<p><strong>sql\u8bed\u53e5\uff1a<\/strong><\/p>\n<pre>update student set score=(select max(score) from score where score.student_id=student.id)<\/pre>\n<p><strong>\u8bf4\u660e\uff1a<\/strong><\/p>\n<p>\u8be5sql\u8bed\u53e5\u4f7f\u7528left 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