{"id":75068,"date":"2024-10-15T23:14:15","date_gmt":"2024-10-15T15:14:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/75068\/"},"modified":"2024-10-15T23:14:16","modified_gmt":"2024-10-15T15:14:16","slug":"mysql-%e4%b8%8d%e7%9b%b8%e9%97%9c%e5%ad%90%e6%9f%a5%e8%a9%a2%e6%80%8e%e9%ba%bc%e5%9f%b7%e8%a1%8c%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/75068\/","title":{"rendered":"MySQL \u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u600e\u9ebc\u57f7\u884c\uff1f"},"content":{"rendered":"<h1 id=\"mysql-%e4%b8%8d%e7%9b%b8%e9%97%9c%e5%ad%90%e6%9f%a5%e8%a9%a2%e6%80%8e%e9%ba%bc%e5%9f%b7%e8%a1%8c%ef%bc%9f-FpqcsxTjlX\">MySQL \u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u600e\u9ebc\u57f7\u884c\uff1f<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL \u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u958b\u6e90\u8cc7\u6599\u5eab\uff0c\u7279\u5225\u662f\u5728\u7db2\u9801\u61c9\u7528\u7a0b\u5f0f\u4e2d\u3002\u7576\u6211\u5011\u9700\u8981\u5f9e\u8cc7\u6599\u5eab\u4e2d\u63d0\u53d6\u7279\u5b9a\u8cc7\u6599\u6642\uff0c\u67e5\u8a62\u7684\u8a2d\u8a08\u81f3\u95dc\u91cd\u8981\u3002\u672c\u6587\u5c07\u63a2\u8a0e MySQL \u4e2d\u7684\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\uff08Non-correlated Subquery\uff09\uff0c\u4e26\u63d0\u4f9b\u57f7\u884c\u9019\u985e\u67e5\u8a62\u7684\u5177\u9ad4\u65b9\u6cd5\u548c\u7bc4\u4f8b\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e4%b8%8d%e7%9b%b8%e9%97%9c%e5%ad%90%e6%9f%a5%e8%a9%a2%ef%bc%9f-FpqcsxTjlX\">\u4ec0\u9ebc\u662f\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\uff1f<\/h2>\n<p>\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u662f\u6307\u5728\u57f7\u884c\u6642\u4e0d\u4f9d\u8cf4\u65bc\u5916\u90e8\u67e5\u8a62\u7684\u5b50\u67e5\u8a62\u3002\u63db\u53e5\u8a71\u8aaa\uff0c\u9019\u985e\u5b50\u67e5\u8a62\u53ef\u4ee5\u7368\u7acb\u57f7\u884c\uff0c\u4e26\u8fd4\u56de\u4e00\u500b\u7d50\u679c\u96c6\uff0c\u8a72\u7d50\u679c\u96c6\u53ef\u4ee5\u88ab\u5916\u90e8\u67e5\u8a62\u4f7f\u7528\u3002\u9019\u8207\u76f8\u95dc\u5b50\u67e5\u8a62\u4e0d\u540c\uff0c\u5f8c\u8005\u5728\u57f7\u884c\u6642\u9700\u8981\u4f9d\u8cf4\u5916\u90e8\u67e5\u8a62\u7684\u7d50\u679c\u3002<\/p>\n<h2 id=\"%e4%b8%8d%e7%9b%b8%e9%97%9c%e5%ad%90%e6%9f%a5%e8%a9%a2%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-FpqcsxTjlX\">\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT column1, column2\nFROM table1\nWHERE column3 IN (SELECT column3 FROM table2 WHERE condition);<\/code><\/pre>\n<p>\u5728\u9019\u500b\u7bc4\u4f8b\u4e2d\uff0c\u5167\u90e8\u7684 SELECT \u8a9e\u53e5\u662f\u7368\u7acb\u7684\uff0c\u4e26\u4e14\u53ef\u4ee5\u5728\u5916\u90e8\u67e5\u8a62\u4e4b\u524d\u57f7\u884c\u3002<\/p>\n<h2 id=\"%e4%b8%8d%e7%9b%b8%e9%97%9c%e5%ad%90%e6%9f%a5%e8%a9%a2%e7%9a%84%e7%af%84%e4%be%8b-FpqcsxTjlX\">\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u7684\u7bc4\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8cc7\u6599\u8868\uff1a<strong>employees<\/strong> \u548c <strong>departments<\/strong>\u3002<strong>employees<\/strong> \u8868\u5305\u542b\u54e1\u5de5\u7684\u8cc7\u8a0a\uff0c\u800c <strong>departments<\/strong> \u8868\u5247\u5305\u542b\u90e8\u9580\u7684\u8cc7\u8a0a\u3002<\/p>\n<p>\u4ee5\u4e0b\u662f\u9019\u5169\u500b\u8868\u7684\u7d50\u69cb\uff1a<\/p>\n<ul>\n<li><strong>employees<\/strong> \u8868\uff1a\n<ul>\n<li>id (INT)<\/li>\n<li>name (VARCHAR)<\/li>\n<li>department_id (INT)<\/li>\n<\/ul>\n<\/li>\n<li><strong>departments<\/strong> \u8868\uff1a\n<ul>\n<li>id (INT)<\/li>\n<li>department_name (VARCHAR)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>\u5982\u679c\u6211\u5011\u60f3\u8981\u67e5\u8a62\u6240\u6709\u5728\u7279\u5b9a\u90e8\u9580\u5de5\u4f5c\u7684\u54e1\u5de5\uff0c\u53ef\u4ee5\u4f7f\u7528\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u4f86\u9054\u6210\uff1a<\/p>\n<pre><code>SELECT name\nFROM employees\nWHERE department_id IN (SELECT id FROM departments WHERE department_name = 'Sales');<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u5167\u90e8\u7684 SELECT \u8a9e\u53e5\u6703\u5148\u57f7\u884c\uff0c\u8fd4\u56de\u6240\u6709\u540d\u70ba &#8216;Sales&#8217; \u7684\u90e8\u9580\u7684 ID\uff0c\u7136\u5f8c\u5916\u90e8\u67e5\u8a62\u6703\u6839\u64da\u9019\u4e9b ID \u67e5\u8a62\u54e1\u5de5\u7684\u540d\u7a31\u3002<\/p>\n<h2 id=\"%e4%b8%8d%e7%9b%b8%e9%97%9c%e5%ad%90%e6%9f%a5%e8%a9%a2%e7%9a%84%e5%84%aa%e7%bc%ba%e9%bb%9e-FpqcsxTjlX\">\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u7684\u512a\u7f3a\u9ede<\/h2>\n<p>\u4f7f\u7528\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u6709\u5176\u512a\u7f3a\u9ede\uff1a<\/p>\n<ul>\n<li><strong>\u512a\u9ede\uff1a<\/strong>\n<ul>\n<li>\u7c21\u55ae\u6613\u61c2\uff0c\u7d50\u69cb\u6e05\u6670\u3002<\/li>\n<li>\u53ef\u4ee5\u7368\u7acb\u57f7\u884c\uff0c\u4fbf\u65bc\u6e2c\u8a66\u548c\u8abf\u8a66\u3002<\/li>\n<\/ul>\n<\/li>\n<li><strong>\u7f3a\u9ede\uff1a<\/strong>\n<ul>\n<li>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u6027\u80fd\u53ef\u80fd\u4e0d\u5982\u806f\u63a5\uff08JOIN\uff09\u67e5\u8a62\u3002<\/li>\n<li>\u5c0d\u65bc\u5927\u578b\u8cc7\u6599\u96c6\uff0c\u53ef\u80fd\u6703\u5c0e\u81f4\u8f03\u6162\u7684\u57f7\u884c\u901f\u5ea6\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-FpqcsxTjlX\">\u7d50\u8ad6<\/h2>\n<p>\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\u5728 MySQL \u4e2d\u662f\u4e00\u7a2e\u5f37\u5927\u7684\u67e5\u8a62\u5de5\u5177\uff0c\u80fd\u5920\u5e6b\u52a9\u958b\u767c\u8005\u5f9e\u8cc7\u6599\u5eab\u4e2d\u63d0\u53d6\u6240\u9700\u7684\u8cc7\u6599\u3002\u96d6\u7136\u5b83\u5011\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\u53ef\u80fd\u4e0d\u5982\u806f\u63a5\u67e5\u8a62\u9ad8\u6548\uff0c\u4f46\u5728\u8a31\u591a\u60c5\u6cc1\u4e0b\uff0c\u5b83\u5011\u63d0\u4f9b\u4e86\u4e00\u7a2e\u7c21\u55ae\u4e14\u76f4\u89c0\u7684\u89e3\u6c7a\u65b9\u6848\u3002\u4e86\u89e3\u5982\u4f55\u6709\u6548\u5730\u4f7f\u7528\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\uff0c\u5c07\u6709\u52a9\u65bc\u63d0\u5347\u8cc7\u6599\u5eab\u67e5\u8a62\u7684\u9748\u6d3b\u6027\u548c\u53ef\u8b80\u6027\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u4e0d\u540c\u9700\u6c42\u7684\u5ba2\u6236\u3002\u7121\u8ad6\u662f\u5c0f\u578b\u4f01\u696d\u9084\u662f\u5927\u578b\u4f01\u696d\uff0c\u6211\u5011\u7684 <a href=\"https:\/\/server.hk\">\u4e91\u670d\u52a1\u5668<\/a> \u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u5728 MySQL \u4e2d\u57f7\u884c\u4e0d\u76f8\u95dc\u5b50\u67e5\u8a62\uff0c\u63d0\u5347\u67e5\u8a62\u6548\u7387\u8207\u6578\u64da\u8655\u7406\u80fd\u529b\uff0c\u7c21\u5316\u6578\u64da\u6aa2\u7d22\u904e\u7a0b\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-75068","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75068","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=75068"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75068\/revisions"}],"predecessor-version":[{"id":75069,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75068\/revisions\/75069"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=75068"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=75068"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=75068"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}