{"id":75726,"date":"2024-10-16T00:42:19","date_gmt":"2024-10-15T16:42:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/75726\/"},"modified":"2024-10-16T00:42:19","modified_gmt":"2024-10-15T16:42:19","slug":"mysql-group_concat%e7%9a%84%e5%85%b7%e9%ab%94%e4%bd%bf%e7%94%a8%e6%96%b9%e6%a1%88","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/75726\/","title":{"rendered":"MySQL GROUP_CONCAT\u7684\u5177\u9ad4\u4f7f\u7528\u65b9\u6848"},"content":{"rendered":"<h1 id=\"mysql-group_concat%e7%9a%84%e5%85%b7%e9%ab%94%e4%bd%bf%e7%94%a8%e6%96%b9%e6%a1%88-eSPayxEjnJ\">MySQL GROUP_CONCAT\u7684\u5177\u9ad4\u4f7f\u7528\u65b9\u6848<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u806f\u6578\u64da\u5eab\u7cfb\u7d71\u3002\u5176\u5f37\u5927\u7684\u67e5\u8a62\u529f\u80fd\u4f7f\u5f97\u7528\u6236\u80fd\u5920\u9ad8\u6548\u5730\u8655\u7406\u548c\u5206\u6790\u6578\u64da\u3002\u5176\u4e2d\uff0c<code>GROUP_CONCAT<\/code>\u51fd\u6578\u662f\u4e00\u500b\u975e\u5e38\u6709\u7528\u7684\u5de5\u5177\uff0c\u80fd\u5920\u5c07\u591a\u884c\u6578\u64da\u5408\u4f75\u70ba\u4e00\u884c\uff0c\u4e26\u4ee5\u7279\u5b9a\u7684\u5206\u9694\u7b26\u9023\u63a5\u3002\u672c\u6587\u5c07\u63a2\u8a0e<code>GROUP_CONCAT<\/code>\u7684\u5177\u9ad4\u4f7f\u7528\u65b9\u6848\u53ca\u5176\u61c9\u7528\u5834\u666f\u3002<\/p>\n<h2 id=\"group_concat%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-eSPayxEjnJ\">GROUP_CONCAT\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p><code>GROUP_CONCAT<\/code>\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>GROUP_CONCAT([DISTINCT] column_name [ORDER BY column_name] [SEPARATOR 'separator'])\n<\/code><\/pre>\n<ul>\n<li><strong>DISTINCT<\/strong>\uff1a\u53ef\u9078\uff0c\u8868\u793a\u53ea\u8fd4\u56de\u4e0d\u540c\u7684\u503c\u3002<\/li>\n<li><strong>column_name<\/strong>\uff1a\u8981\u5408\u4f75\u7684\u5217\u540d\u3002<\/li>\n<li><strong>ORDER BY<\/strong>\uff1a\u53ef\u9078\uff0c\u6307\u5b9a\u5408\u4f75\u5f8c\u7684\u503c\u7684\u6392\u5e8f\u65b9\u5f0f\u3002<\/li>\n<li><strong>SEPARATOR<\/strong>\uff1a\u53ef\u9078\uff0c\u6307\u5b9a\u5408\u4f75\u5f8c\u7684\u5206\u9694\u7b26\uff0c\u9ed8\u8a8d\u70ba\u9017\u865f\uff08,\uff09\u3002<\/li>\n<\/ul>\n<h2 id=\"%e4%bd%bf%e7%94%a8%e7%af%84%e4%be%8b-eSPayxEjnJ\">\u4f7f\u7528\u7bc4\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u7bc4\u4f8b\uff0c\u5c55\u793a\u5982\u4f55\u4f7f\u7528<code>GROUP_CONCAT<\/code>\u4f86\u5408\u4f75\u6578\u64da\u3002<\/p>\n<pre><code>SELECT department, GROUP_CONCAT(employee_name SEPARATOR ', ') AS employees\nFROM employees\nGROUP BY department;\n<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u5f9e<code>employees<\/code>\u8868\u4e2d\u9078\u64c7\u6bcf\u500b\u90e8\u9580\u53ca\u5176\u6240\u6709\u54e1\u5de5\u7684\u540d\u5b57\uff0c\u4e26\u5c07\u54e1\u5de5\u540d\u5b57\u5408\u4f75\u70ba\u4e00\u500b\u5b57\u7b26\u4e32\uff0c\u4f7f\u7528\u9017\u865f\u4f5c\u70ba\u5206\u9694\u7b26\u3002\u7d50\u679c\u5c07\u986f\u793a\u6bcf\u500b\u90e8\u9580\u53ca\u5176\u5c0d\u61c9\u7684\u54e1\u5de5\u5217\u8868\u3002<\/p>\n<h2 id=\"%e9%80%b2%e9%9a%8e%e7%94%a8%e6%b3%95-eSPayxEjnJ\">\u9032\u968e\u7528\u6cd5<\/h2>\n<p>\u9664\u4e86\u57fa\u672c\u7684\u5408\u4f75\u529f\u80fd\uff0c<code>GROUP_CONCAT<\/code>\u9084\u53ef\u4ee5\u8207\u5176\u4ed6\u51fd\u6578\u7d50\u5408\u4f7f\u7528\uff0c\u4ee5\u5be6\u73fe\u66f4\u8907\u96dc\u7684\u67e5\u8a62\u3002\u4f8b\u5982\uff0c\u6211\u5011\u53ef\u4ee5\u4f7f\u7528<code>ORDER BY<\/code>\u4f86\u63a7\u5236\u5408\u4f75\u5f8c\u7684\u9806\u5e8f\uff1a<\/p>\n<pre><code>SELECT department, GROUP_CONCAT(employee_name ORDER BY employee_name ASC SEPARATOR ', ') AS employees\nFROM employees\nGROUP BY department;\n<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u54e1\u5de5\u540d\u5b57\u5c07\u6309\u7167\u5b57\u6bcd\u9806\u5e8f\u6392\u5217\uff0c\u4e26\u5408\u4f75\u70ba\u4e00\u500b\u5b57\u7b26\u4e32\u3002<\/p>\n<h2 id=\"%e6%87%89%e7%94%a8%e5%a0%b4%e6%99%af-eSPayxEjnJ\">\u61c9\u7528\u5834\u666f<\/h2>\n<p><code>GROUP_CONCAT<\/code>\u51fd\u6578\u5728\u8a31\u591a\u5834\u666f\u4e2d\u90fd\u975e\u5e38\u6709\u7528\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u61c9\u7528\uff1a<\/p>\n<ul>\n<li><strong>\u5831\u544a\u751f\u6210<\/strong>\uff1a\u5728\u751f\u6210\u5831\u544a\u6642\uff0c\u53ef\u4ee5\u5c07\u591a\u500b\u76f8\u95dc\u6578\u64da\u5408\u4f75\u70ba\u4e00\u884c\uff0c\u4fbf\u65bc\u95b1\u8b80\u548c\u5206\u6790\u3002<\/li>\n<li><strong>\u6578\u64da\u532f\u7e3d<\/strong>\uff1a\u5728\u6578\u64da\u532f\u7e3d\u6642\uff0c\u53ef\u4ee5\u5c07\u591a\u884c\u6578\u64da\u5408\u4f75\uff0c\u6e1b\u5c11\u6578\u64da\u7684\u5197\u9918\u3002<\/li>\n<li><strong>\u6578\u64da\u5c55\u793a<\/strong>\uff1a\u5728\u524d\u7aef\u5c55\u793a\u6578\u64da\u6642\uff0c\u53ef\u4ee5\u5c07\u591a\u500b\u503c\u5408\u4f75\u70ba\u4e00\u500b\u5b57\u7b26\u4e32\uff0c\u63d0\u5347\u7528\u6236\u9ad4\u9a57\u3002<\/li>\n<\/ul>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-eSPayxEjnJ\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u4f7f\u7528<code>GROUP_CONCAT<\/code>\u6642\u9700\u8981\u6ce8\u610f\u4ee5\u4e0b\u5e7e\u9ede\uff1a<\/p>\n<ul>\n<li>\u9ed8\u8a8d\u60c5\u6cc1\u4e0b\uff0c<code>GROUP_CONCAT<\/code>\u7684\u8fd4\u56de\u503c\u9577\u5ea6\u9650\u5236\u70ba1024\u5b57\u7bc0\uff0c\u53ef\u4ee5\u901a\u904e\u8a2d\u7f6e<code>group_concat_max_len<\/code>\u8b8a\u91cf\u4f86\u8abf\u6574\u3002<\/li>\n<li>\u5982\u679c\u5408\u4f75\u7684\u6578\u64da\u91cf\u904e\u5927\uff0c\u53ef\u80fd\u6703\u5c0e\u81f4\u6027\u80fd\u554f\u984c\uff0c\u56e0\u6b64\u5728\u4f7f\u7528\u6642\u61c9\u8b39\u614e\u8003\u616e\u6578\u64da\u91cf\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-eSPayxEjnJ\">\u7e3d\u7d50<\/h2>\n<p>MySQL\u7684<code>GROUP_CONCAT<\/code>\u51fd\u6578\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u80fd\u5920\u6709\u6548\u5730\u5408\u4f75\u591a\u884c\u6578\u64da\uff0c\u4e26\u5728\u6578\u64da\u5206\u6790\u548c\u5831\u544a\u751f\u6210\u4e2d\u767c\u63ee\u91cd\u8981\u4f5c\u7528\u3002\u901a\u904e\u9748\u6d3b\u904b\u7528<code>GROUP_CONCAT<\/code>\uff0c\u7528\u6236\u53ef\u4ee5\u66f4\u9ad8\u6548\u5730\u8655\u7406\u548c\u5c55\u793a\u6578\u64da\uff0c\u63d0\u5347\u5de5\u4f5c\u6548\u7387\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u7528\u6236\uff0c\u9078\u64c7\u5408\u9069\u7684<code>VPS<\/code>\u89e3\u6c7a\u65b9\u6848\uff0c\u5982<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\uff0c\u53ef\u4ee5\u9032\u4e00\u6b65\u63d0\u5347\u6578\u64da\u5eab\u6027\u80fd\u548c\u7a69\u5b9a\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22MySQL GROUP_CONCAT\u7684\u5177\u9ad4\u4f7f\u7528\u65b9\u6848\uff0c\u5b78\u7fd2\u5982\u4f55\u6709\u6548\u5730\u5408\u4f75\u591a\u884c\u6578\u64da\uff0c\u63d0\u5347\u6578\u64da\u67e5\u8a62\u6548\u7387\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-75726","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75726","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=75726"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75726\/revisions"}],"predecessor-version":[{"id":75727,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75726\/revisions\/75727"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=75726"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=75726"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=75726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}