{"id":177921,"date":"2024-11-08T16:40:27","date_gmt":"2024-11-08T08:40:27","guid":{"rendered":"https:\/\/server.hk\/cnblog\/177921\/"},"modified":"2024-11-08T16:40:28","modified_gmt":"2024-11-08T08:40:28","slug":"%e5%a6%82%e4%bd%95%e4%bf%ae%e5%be%a9mysql%e9%8c%af%e8%aa%a41242-sqlstate-21000-er_subquery_no_1_row-%e5%ad%90%e6%9f%a5%e8%a9%a2%e8%bf%94%e5%9b%9e%e5%a4%9a%e4%ba%8e1%e8%a1%8c","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/177921\/","title":{"rendered":"\u5982\u4f55\u4fee\u5fa9MySQL\u932f\u8aa41242 &#8211; SQLSTATE: 21000 (ER_SUBQUERY_NO_1_ROW) \u5b50\u67e5\u8a62\u8fd4\u56de\u591a\u4e8e1\u884c"},"content":{"rendered":"<h1 id=\"%e5%a6%82%e4%bd%95%e4%bf%ae%e5%be%a9mysql%e9%8c%af%e8%aa%a41242-sqlstate-21000-er_subquery_no_1_row-%e5%ad%90%e6%9f%a5%e8%a9%a2%e8%bf%94%e5%9b%9e%e5%a4%9a%e4%ba%8e1%e8%a1%8c-ZlgbdVPLfI\">\u5982\u4f55\u4fee\u5fa9MySQL\u932f\u8aa41242 &#8211; SQLSTATE: 21000 (ER_SUBQUERY_NO_1_ROW) \u5b50\u67e5\u8a62\u8fd4\u56de\u591a\u4e8e1\u884c<\/h1>\n<p>\u5728\u4f7f\u7528MySQL\u9032\u884c\u6578\u64da\u5eab\u64cd\u4f5c\u6642\uff0c\u958b\u767c\u8005\u53ef\u80fd\u6703\u9047\u5230\u5404\u7a2e\u932f\u8aa4\uff0c\u5176\u4e2d\u4e4b\u4e00\u5c31\u662f\u932f\u8aa41242\uff0c\u8a72\u932f\u8aa4\u7684\u4ee3\u78bc\u70baSQLSTATE: 21000\uff0c\u8868\u793a\u5b50\u67e5\u8a62\u8fd4\u56de\u4e86\u591a\u4e8e1\u884c\u7684\u7d50\u679c\u3002\u9019\u7a2e\u60c5\u6cc1\u901a\u5e38\u767c\u751f\u5728\u9700\u8981\u55ae\u4e00\u503c\u7684\u4e0a\u4e0b\u6587\u4e2d\u4f7f\u7528\u4e86\u8fd4\u56de\u591a\u884c\u7684\u5b50\u67e5\u8a62\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u8a72\u932f\u8aa4\u7684\u6210\u56e0\u3001\u5f71\u97ff\u4ee5\u53ca\u4fee\u5fa9\u65b9\u6cd5\u3002<\/p>\n<h2 id=\"%e9%8c%af%e8%aa%a41242%e7%9a%84%e6%88%90%e5%9b%a0-ZlgbdVPLfI\">\u932f\u8aa41242\u7684\u6210\u56e0<\/h2>\n<p>\u932f\u8aa41242\u901a\u5e38\u51fa\u73fe\u5728\u4ee5\u4e0b\u60c5\u6cc1\uff1a<\/p>\n<ul>\n<li>\u5728SELECT\u8a9e\u53e5\u4e2d\u4f7f\u7528\u4e86\u5b50\u67e5\u8a62\uff0c\u4e26\u671f\u671b\u8a72\u5b50\u67e5\u8a62\u8fd4\u56de\u55ae\u4e00\u503c\uff0c\u4f46\u5be6\u969b\u4e0a\u8fd4\u56de\u4e86\u591a\u884c\u3002<\/li>\n<li>\u5728WHERE\u5b50\u53e5\u4e2d\u4f7f\u7528\u4e86IN\u6216EXISTS\u7b49\u64cd\u4f5c\u7b26\uff0c\u9019\u4e9b\u64cd\u4f5c\u7b26\u671f\u671b\u4e00\u500b\u55ae\u4e00\u7684\u503c\uff0c\u4f46\u5b50\u67e5\u8a62\u537b\u8fd4\u56de\u4e86\u591a\u884c\u3002<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u8003\u616e\u4ee5\u4e0bSQL\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT name FROM employees WHERE department_id = (SELECT department_id FROM departments WHERE location = 'New York');<\/code><\/pre>\n<p>\u5982\u679c\u5b50\u67e5\u8a62\u8fd4\u56de\u591a\u4e8e\u4e00\u500b\u90e8\u9580ID\uff0c\u5247\u6703\u5f15\u767c\u932f\u8aa41242\u3002\u9019\u662f\u56e0\u70ba\u4e3b\u67e5\u8a62\u671f\u671b\u4e00\u500b\u55ae\u4e00\u7684\u90e8\u9580ID\u4f86\u9032\u884c\u6bd4\u8f03\uff0c\u4f46\u5b50\u67e5\u8a62\u537b\u63d0\u4f9b\u4e86\u591a\u500b\u90e8\u9580ID\u3002<\/p>\n<h2 id=\"%e5%a6%82%e4%bd%95%e4%bf%ae%e5%be%a9%e9%8c%af%e8%aa%a41242-ZlgbdVPLfI\">\u5982\u4f55\u4fee\u5fa9\u932f\u8aa41242<\/h2>\n<p>\u4fee\u5fa9\u932f\u8aa41242\u7684\u65b9\u6cd5\u4e3b\u8981\u6709\u4ee5\u4e0b\u5e7e\u7a2e\uff1a<\/p>\n<h3 id=\"1-%e4%bd%bf%e7%94%a8limit%e9%99%90%e5%88%b6%e8%bf%94%e5%9b%9e%e8%a1%8c%e6%95%b8-ZlgbdVPLfI\">1. \u4f7f\u7528LIMIT\u9650\u5236\u8fd4\u56de\u884c\u6578<\/h3>\n<p>\u5982\u679c\u60a8\u78ba\u5b9a\u5b50\u67e5\u8a62\u53ea\u9700\u8fd4\u56de\u4e00\u884c\uff0c\u53ef\u4ee5\u4f7f\u7528LIMIT\u5b50\u53e5\u4f86\u9650\u5236\u8fd4\u56de\u7684\u884c\u6578\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT name FROM employees WHERE department_id = (SELECT department_id FROM departments WHERE location = 'New York' LIMIT 1);<\/code><\/pre>\n<p>\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u5b50\u67e5\u8a62\u53ea\u8fd4\u56de\u4e00\u884c\uff0c\u5f9e\u800c\u907f\u514d\u932f\u8aa4\u3002<\/p>\n<h3 id=\"2-%e4%bd%bf%e7%94%a8in%e6%88%96exists%e6%93%8d%e4%bd%9c%e7%ac%a6-ZlgbdVPLfI\">2. \u4f7f\u7528IN\u6216EXISTS\u64cd\u4f5c\u7b26<\/h3>\n<p>\u5982\u679c\u5b50\u67e5\u8a62\u53ef\u80fd\u8fd4\u56de\u591a\u884c\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528IN\u64cd\u4f5c\u7b26\u4f86\u8655\u7406\u591a\u884c\u7d50\u679c\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT name FROM employees WHERE department_id IN (SELECT department_id FROM departments WHERE location = 'New York');<\/code><\/pre>\n<p>\u9019\u6a23\uff0c\u4e3b\u67e5\u8a62\u5c07\u80fd\u5920\u8655\u7406\u591a\u500b\u90e8\u9580ID\uff0c\u800c\u4e0d\u6703\u5f15\u767c\u932f\u8aa4\u3002<\/p>\n<h3 id=\"3-%e6%aa%a2%e6%9f%a5%e6%95%b8%e6%93%9a%e9%82%8f%e8%bc%af-ZlgbdVPLfI\">3. \u6aa2\u67e5\u6578\u64da\u908f\u8f2f<\/h3>\n<p>\u6709\u6642\u5019\uff0c\u932f\u8aa4\u7684\u6839\u672c\u539f\u56e0\u5728\u65bc\u6578\u64da\u908f\u8f2f\u3002\u60a8\u61c9\u8a72\u6aa2\u67e5\u5b50\u67e5\u8a62\u7684\u908f\u8f2f\uff0c\u78ba\u4fdd\u5b83\u5728\u7279\u5b9a\u60c5\u6cc1\u4e0b\u53ea\u8fd4\u56de\u4e00\u884c\u3002\u5982\u679c\u9700\u8981\uff0c\u60a8\u53ef\u4ee5\u8003\u616e\u4f7f\u7528GROUP BY\u6216\u5176\u4ed6\u805a\u5408\u51fd\u6578\u4f86\u78ba\u4fdd\u8fd4\u56de\u7684\u7d50\u679c\u7b26\u5408\u9810\u671f\u3002<\/p>\n<pre><code>SELECT name FROM employees WHERE department_id = (SELECT MAX(department_id) FROM departments WHERE location = 'New York');<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-ZlgbdVPLfI\">\u7e3d\u7d50<\/h2>\n<p>MySQL\u932f\u8aa41242 &#8211; SQLSTATE: 21000 (ER_SUBQUERY_NO_1_ROW) \u662f\u4e00\u500b\u5e38\u898b\u7684\u932f\u8aa4\uff0c\u901a\u5e38\u7531\u65bc\u5b50\u67e5\u8a62\u8fd4\u56de\u591a\u4e8e\u4e00\u884c\u800c\u5f15\u8d77\u3002\u901a\u904e\u4f7f\u7528LIMIT\u3001IN\u64cd\u4f5c\u7b26\u6216\u6aa2\u67e5\u6578\u64da\u908f\u8f2f\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u6709\u6548\u5730\u4fee\u5fa9\u6b64\u932f\u8aa4\u3002\u4e86\u89e3\u9019\u4e9b\u4fee\u5fa9\u65b9\u6cd5\u4e0d\u50c5\u80fd\u63d0\u9ad8\u958b\u767c\u6548\u7387\uff0c\u9084\u80fd\u5e6b\u52a9\u7dad\u8b77\u6578\u64da\u5eab\u7684\u7a69\u5b9a\u6027\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u9069\u5408\u5404\u7a2e\u9700\u6c42\u3002\u7121\u8ad6\u662f <a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a> \u9084\u662f <a href=\"https:\/\/server.hk\">\u4e91\u4f3a\u670d\u5668<\/a>\uff0c\u6211\u5011\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u4fee\u5fa9MySQL\u932f\u8aa41242 (ER_SUBQUERY_NO_1_ROW)\uff0c\u89e3\u6c7a\u5b50\u67e5\u8a62\u8fd4\u56de\u591a\u4e8e1\u884c\u7684\u554f\u984c\uff0c\u78ba\u4fdd\u67e5\u8a62\u6b63\u78ba\u57f7\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-177921","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/177921","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=177921"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/177921\/revisions"}],"predecessor-version":[{"id":177922,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/177921\/revisions\/177922"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=177921"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=177921"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=177921"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}