{"id":175513,"date":"2024-11-08T06:30:15","date_gmt":"2024-11-07T22:30:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/175513\/"},"modified":"2024-11-08T06:30:16","modified_gmt":"2024-11-07T22:30:16","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84max%e5%87%bd%e6%95%b8%e9%80%b2%e8%a1%8c%e6%b8%9b%e6%b3%95%e8%a8%88%e7%ae%97%ef%bc%9f-%e6%95%b8%e6%93%9a%e5%ba%abmax","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/175513\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528\u6578\u64da\u5eab\u4e2d\u7684MAX\u51fd\u6578\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\uff1f (\u6578\u64da\u5eabmax\u51fd\u6578\u6e1b\u6cd5)"},"content":{"rendered":"<h1 id=\"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84max%e5%87%bd%e6%95%b8%e9%80%b2%e8%a1%8c%e6%b8%9b%e6%b3%95%e8%a8%88%e7%ae%97%ef%bc%9f-%e6%95%b8%e6%93%9a%e5%ba%abmax-dBDSuBXsLG\">\u5982\u4f55\u4f7f\u7528\u6578\u64da\u5eab\u4e2d\u7684MAX\u51fd\u6578\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\uff1f (\u6578\u64da\u5eabmax\u51fd\u6578\u6e1b\u6cd5)<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMAX\u51fd\u6578\u662f\u4e00\u500b\u975e\u5e38\u6709\u7528\u7684\u805a\u5408\u51fd\u6578\uff0c\u901a\u5e38\u7528\u65bc\u67e5\u8a62\u67d0\u4e00\u5217\u4e2d\u7684\u6700\u5927\u503c\u3002\u7136\u800c\uff0c\u9664\u4e86\u67e5\u8a62\u6700\u5927\u503c\u4e4b\u5916\uff0cMAX\u51fd\u6578\u4e5f\u53ef\u4ee5\u8207\u5176\u4ed6\u6578\u5b78\u904b\u7b97\u7d50\u5408\u4f7f\u7528\uff0c\u9032\u884c\u66f4\u8907\u96dc\u7684\u8a08\u7b97\uff0c\u4f8b\u5982\u6e1b\u6cd5\u8a08\u7b97\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u5728\u6578\u64da\u5eab\u4e2d\u4f7f\u7528MAX\u51fd\u6578\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\uff0c\u4e26\u63d0\u4f9b\u76f8\u95dc\u7684\u793a\u4f8b\u548c\u4ee3\u78bc\u7247\u6bb5\u3002<\/p>\n<h2 id=\"max%e5%87%bd%e6%95%b8%e7%9a%84%e5%9f%ba%e6%9c%ac%e7%94%a8%e6%b3%95-dBDSuBXsLG\">MAX\u51fd\u6578\u7684\u57fa\u672c\u7528\u6cd5<\/h2>\n<p>MAX\u51fd\u6578\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT MAX(column_name) FROM table_name;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6307\u5b9a\u5217\u4e2d\u7684\u6700\u5927\u503c\u3002\u8209\u4f8b\u4f86\u8aaa\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba\u201csales\u201d\u7684\u8868\u683c\uff0c\u5305\u542b\u201camount\u201d\u5217\uff0c\u8a18\u9304\u4e86\u6bcf\u7b46\u92b7\u552e\u7684\u91d1\u984d\u3002\u6211\u5011\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\u4f86\u7372\u53d6\u6700\u9ad8\u92b7\u552e\u91d1\u984d\uff1a<\/p>\n<pre><code>SELECT MAX(amount) FROM sales;<\/code><\/pre>\n<h2 id=\"%e4%bd%bf%e7%94%a8max%e5%87%bd%e6%95%b8%e9%80%b2%e8%a1%8c%e6%b8%9b%e6%b3%95%e8%a8%88%e7%ae%97-dBDSuBXsLG\">\u4f7f\u7528MAX\u51fd\u6578\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97<\/h2>\n<p>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u6211\u5011\u53ef\u80fd\u9700\u8981\u8a08\u7b97\u67d0\u500b\u503c\u8207\u6700\u5927\u503c\u4e4b\u9593\u7684\u5dee\u7570\u3002\u9019\u6642\uff0c\u6211\u5011\u53ef\u4ee5\u5c07MAX\u51fd\u6578\u8207\u6e1b\u6cd5\u904b\u7b97\u7d50\u5408\u4f7f\u7528\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff0c\u5047\u8a2d\u6211\u5011\u60f3\u8981\u8a08\u7b97\u6bcf\u7b46\u92b7\u552e\u91d1\u984d\u8207\u6700\u9ad8\u92b7\u552e\u91d1\u984d\u4e4b\u9593\u7684\u5dee\u7570\uff1a<\/p>\n<pre><code>SELECT amount, (SELECT MAX(amount) FROM sales) - amount AS difference\nFROM sales;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c\u6211\u5011\u9996\u5148\u7372\u53d6\u6bcf\u7b46\u92b7\u552e\u91d1\u984d\uff0c\u7136\u5f8c\u901a\u904e\u5b50\u67e5\u8a62\u7372\u53d6\u6700\u9ad8\u92b7\u552e\u91d1\u984d\uff0c\u4e26\u5c07\u5176\u8207\u6bcf\u7b46\u91d1\u984d\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\u3002\u7d50\u679c\u5c07\u986f\u793a\u6bcf\u7b46\u92b7\u552e\u91d1\u984d\u8207\u6700\u9ad8\u92b7\u552e\u91d1\u984d\u4e4b\u9593\u7684\u5dee\u7570\u3002<\/p>\n<h2 id=\"%e5%af%a6%e9%9a%9b%e6%87%89%e7%94%a8%e5%a0%b4%e6%99%af-dBDSuBXsLG\">\u5be6\u969b\u61c9\u7528\u5834\u666f<\/h2>\n<p>\u4f7f\u7528MAX\u51fd\u6578\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\u7684\u61c9\u7528\u5834\u666f\u975e\u5e38\u5ee3\u6cdb\u3002\u4f8b\u5982\uff0c\u5728\u92b7\u552e\u5831\u544a\u4e2d\uff0c\u6211\u5011\u53ef\u80fd\u9700\u8981\u5206\u6790\u6bcf\u500b\u7522\u54c1\u7684\u92b7\u552e\u8868\u73fe\uff0c\u4e26\u627e\u51fa\u54ea\u4e9b\u7522\u54c1\u7684\u92b7\u552e\u984d\u8ddd\u96e2\u6700\u9ad8\u92b7\u552e\u984d\u9084\u6709\u591a\u9060\u3002\u9019\u6a23\u7684\u5206\u6790\u53ef\u4ee5\u5e6b\u52a9\u4f01\u696d\u5236\u5b9a\u66f4\u6709\u6548\u7684\u92b7\u552e\u7b56\u7565\u3002<\/p>\n<p>\u53e6\u4e00\u500b\u4f8b\u5b50\u662f\u5728\u8ca1\u52d9\u5831\u544a\u4e2d\uff0c\u4f01\u696d\u53ef\u80fd\u9700\u8981\u8a08\u7b97\u6bcf\u500b\u90e8\u9580\u7684\u652f\u51fa\u8207\u6700\u9ad8\u652f\u51fa\u4e4b\u9593\u7684\u5dee\u7570\uff0c\u4ee5\u4fbf\u66f4\u597d\u5730\u63a7\u5236\u9810\u7b97\u3002\u901a\u904e\u9019\u7a2e\u65b9\u5f0f\uff0c\u4f01\u696d\u53ef\u4ee5\u8b58\u5225\u51fa\u54ea\u4e9b\u90e8\u9580\u7684\u652f\u51fa\u904e\u9ad8\uff0c\u4e26\u9032\u884c\u76f8\u61c9\u7684\u8abf\u6574\u3002<\/p>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-dBDSuBXsLG\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5728\u4f7f\u7528MAX\u51fd\u6578\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\u6642\uff0c\u6709\u5e7e\u9ede\u9700\u8981\u6ce8\u610f\uff1a<\/p>\n<ul>\n<li>\u78ba\u4fdd\u5b50\u67e5\u8a62\u8fd4\u56de\u7684\u7d50\u679c\u662f\u55ae\u4e00\u503c\uff0c\u5426\u5247\u6703\u5c0e\u81f4\u932f\u8aa4\u3002<\/li>\n<li>\u5728\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\uff0c\u6027\u80fd\u53ef\u80fd\u6703\u53d7\u5230\u5f71\u97ff\uff0c\u7279\u5225\u662f\u7576\u5b50\u67e5\u8a62\u9700\u8981\u591a\u6b21\u57f7\u884c\u6642\u3002<\/li>\n<li>\u8003\u616e\u4f7f\u7528\u7d22\u5f15\u4f86\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\uff0c\u7279\u5225\u662f\u5728\u5927\u578b\u6578\u64da\u96c6\u4e0a\u9032\u884c\u805a\u5408\u8a08\u7b97\u6642\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-dBDSuBXsLG\">\u7e3d\u7d50<\/h2>\n<p>MAX\u51fd\u6578\u4e0d\u50c5\u53ef\u4ee5\u7528\u4f86\u67e5\u8a62\u6700\u5927\u503c\uff0c\u9084\u53ef\u4ee5\u8207\u5176\u4ed6\u6578\u5b78\u904b\u7b97\u7d50\u5408\u4f7f\u7528\uff0c\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\u3002\u901a\u904e\u5408\u7406\u5730\u4f7f\u7528MAX\u51fd\u6578\uff0c\u6578\u64da\u5eab\u7528\u6236\u53ef\u4ee5\u7372\u5f97\u66f4\u6df1\u5165\u7684\u6578\u64da\u5206\u6790\uff0c\u5f9e\u800c\u505a\u51fa\u66f4\u660e\u667a\u7684\u5546\u696d\u6c7a\u7b56\u3002\u5982\u679c\u60a8\u9700\u8981\u9ad8\u6548\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u4f86\u652f\u6301\u60a8\u7684\u696d\u52d9\u9700\u6c42\uff0c\u7121\u8ad6\u662f\u6578\u64da\u5b58\u5132\u9084\u662f\u6578\u64da\u8655\u7406\uff0c\u5747\u80fd\u63d0\u4f9b\u7a69\u5b9a\u7684\u6027\u80fd\u548c\u9748\u6d3b\u7684\u64f4\u5c55\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u5728\u6578\u64da\u5eab\u4e2d\u4f7f\u7528MAX\u51fd\u6578\u9032\u884c\u6e1b\u6cd5\u8a08\u7b97\uff0c\u638c\u63e1\u6578\u64da\u5206\u6790\u6280\u5de7\uff0c\u63d0\u5347\u67e5\u8a62\u6548\u7387\u8207\u6e96\u78ba\u6027\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-175513","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175513","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=175513"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175513\/revisions"}],"predecessor-version":[{"id":175514,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175513\/revisions\/175514"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=175513"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=175513"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=175513"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}