{"id":76214,"date":"2024-10-16T04:48:15","date_gmt":"2024-10-15T20:48:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/76214\/"},"modified":"2024-10-16T04:48:15","modified_gmt":"2024-10-15T20:48:15","slug":"mysql%e5%85%a5%e9%96%80%ef%bc%9a%e4%bd%bf%e7%94%a8distinct%e9%97%9c%e9%8d%b5%e5%ad%97%e5%83%85%e8%bf%94%e5%9b%9e%e4%b8%8d%e5%90%8c%ef%bc%88%e5%94%af%e4%b8%80%ef%bc%89%e7%9a%84%e5%80%bc%e3%80%82","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/76214\/","title":{"rendered":"MySQL\u5165\u9580\uff1a\u4f7f\u7528DISTINCT\u95dc\u9375\u5b57\u50c5\u8fd4\u56de\u4e0d\u540c\uff08\u552f\u4e00\uff09\u7684\u503c\u3002"},"content":{"rendered":"<h1 id=\"mysql%e5%85%a5%e9%96%80%ef%bc%9a%e4%bd%bf%e7%94%a8distinct%e9%97%9c%e9%8d%b5%e5%ad%97%e5%83%85%e8%bf%94%e5%9b%9e%e4%b8%8d%e5%90%8c%ef%bc%88%e5%94%af%e4%b8%80%ef%bc%89%e7%9a%84%e5%80%bc-AlSvMXrbue\">MySQL\u5165\u9580\uff1a\u4f7f\u7528DISTINCT\u95dc\u9375\u5b57\u50c5\u8fd4\u56de\u4e0d\u540c\uff08\u552f\u4e00\uff09\u7684\u503c<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u958b\u6e90\u95dc\u806f\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u3002\u5b83\u7684\u9748\u6d3b\u6027\u548c\u9ad8\u6548\u6027\u4f7f\u5176\u6210\u70ba\u8a31\u591a\u61c9\u7528\u7a0b\u5e8f\u7684\u9996\u9078\u3002\u7576\u6211\u5011\u9700\u8981\u5f9e\u6578\u64da\u8868\u4e2d\u63d0\u53d6\u552f\u4e00\u7684\u6578\u64da\u6642\uff0cDISTINCT\u95dc\u9375\u5b57\u4fbf\u6210\u70ba\u4e00\u500b\u975e\u5e38\u6709\u7528\u7684\u5de5\u5177\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528DISTINCT\u95dc\u9375\u5b57\u4f86\u7372\u53d6\u4e0d\u540c\u7684\u503c\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%afdistinct%e9%97%9c%e9%8d%b5%e5%ad%97%ef%bc%9f-AlSvMXrbue\">\u4ec0\u9ebc\u662fDISTINCT\u95dc\u9375\u5b57\uff1f<\/h2>\n<p>DISTINCT\u95dc\u9375\u5b57\u7528\u65bcSQL\u67e5\u8a62\u4e2d\uff0c\u4ee5\u78ba\u4fdd\u8fd4\u56de\u7684\u7d50\u679c\u96c6\u4e2d\u4e0d\u5305\u542b\u91cd\u8907\u7684\u6578\u64da\u884c\u3002\u9019\u5c0d\u65bc\u9700\u8981\u5206\u6790\u6216\u986f\u793a\u552f\u4e00\u6578\u64da\u7684\u60c5\u6cc1\u7279\u5225\u91cd\u8981\u3002\u4f8b\u5982\uff0c\u7576\u6211\u5011\u60f3\u8981\u7372\u53d6\u67d0\u500b\u5217\u4e2d\u6240\u6709\u4e0d\u540c\u7684\u503c\u6642\uff0c\u4f7f\u7528DISTINCT\u53ef\u4ee5\u5e6b\u52a9\u6211\u5011\u9054\u6210\u9019\u4e00\u76ee\u6a19\u3002<\/p>\n<h2 id=\"%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-AlSvMXrbue\">\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>\u4f7f\u7528DISTINCT\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT DISTINCT column1, column2, ...\nFROM table_name;\n<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0ccolumn1\u548ccolumn2\u662f\u4f60\u5e0c\u671b\u67e5\u8a62\u7684\u5217\u540d\uff0c\u800ctable_name\u5247\u662f\u6578\u64da\u8868\u7684\u540d\u7a31\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8%e7%af%84%e4%be%8b-AlSvMXrbue\">\u4f7f\u7528\u7bc4\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba\u201ccustomers\u201d\u7684\u6578\u64da\u8868\uff0c\u8a72\u8868\u5305\u542b\u4ee5\u4e0b\u6578\u64da\uff1a<\/p>\n<pre><code>+----+----------+-----------+\n| id | name     | country   |\n+----+----------+-----------+\n| 1  | Alice    | USA       |\n| 2  | Bob      | UK        |\n| 3  | Charlie  | USA       |\n| 4  | David    | Canada     |\n| 5  | Eve      | UK        |\n+----+----------+-----------+\n<\/code><\/pre>\n<p>\u5982\u679c\u6211\u5011\u60f3\u8981\u67e5\u8a62\u6240\u6709\u4e0d\u540c\u7684\u570b\u5bb6\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bSQL\u8a9e\u53e5\uff1a<\/p>\n<pre><code>SELECT DISTINCT country\nFROM customers;\n<\/code><\/pre>\n<p>\u57f7\u884c\u9019\u500b\u67e5\u8a62\u5f8c\uff0c\u8fd4\u56de\u7684\u7d50\u679c\u5c07\u662f\uff1a<\/p>\n<pre><code>+-----------+\n| country   |\n+-----------+\n| USA       |\n| UK        |\n| Canada    |\n+-----------+\n<\/code><\/pre>\n<h2 id=\"%e5%a4%9a%e5%88%97%e6%9f%a5%e8%a9%a2-AlSvMXrbue\">\u591a\u5217\u67e5\u8a62<\/h2>\n<p>\u9664\u4e86\u67e5\u8a62\u55ae\u4e00\u5217\u5916\uff0cDISTINCT\u9084\u53ef\u4ee5\u7528\u65bc\u591a\u5217\u67e5\u8a62\u3002\u7576\u4f60\u5e0c\u671b\u7372\u53d6\u591a\u500b\u5217\u7684\u552f\u4e00\u7d44\u5408\u6642\uff0c\u53ef\u4ee5\u9019\u6a23\u505a\uff1a<\/p>\n<pre><code>SELECT DISTINCT name, country\nFROM customers;\n<\/code><\/pre>\n<p>\u9019\u5c07\u8fd4\u56de\u6240\u6709\u4e0d\u540c\u7684\u59d3\u540d\u548c\u570b\u5bb6\u7d44\u5408\uff0c\u7d50\u679c\u53ef\u80fd\u5982\u4e0b\uff1a<\/p>\n<pre><code>+----------+-----------+\n| name     | country   |\n+----------+-----------+\n| Alice    | USA       |\n| Bob      | UK        |\n| Charlie  | USA       |\n| David    | Canada    |\n| Eve      | UK        |\n+----------+-----------+\n<\/code><\/pre>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-AlSvMXrbue\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5728\u4f7f\u7528DISTINCT\u6642\uff0c\u6709\u5e7e\u9ede\u9700\u8981\u6ce8\u610f\uff1a<\/p>\n<ul>\n<li>\u4f7f\u7528DISTINCT\u6703\u589e\u52a0\u67e5\u8a62\u7684\u8a08\u7b97\u8ca0\u64d4\uff0c\u7279\u5225\u662f\u5728\u5927\u578b\u6578\u64da\u96c6\u4e0a\uff0c\u56e0\u6b64\u61c9\u8b39\u614e\u4f7f\u7528\u3002<\/li>\n<li>DISTINCT\u50c5\u9069\u7528\u65bc\u9078\u64c7\u7684\u5217\uff0c\u82e5\u67e5\u8a62\u4e2d\u5305\u542b\u5176\u4ed6\u5217\uff0c\u5247\u4e0d\u6703\u5f71\u97ff\u7d50\u679c\u3002<\/li>\n<li>\u5982\u679c\u6240\u6709\u9078\u64c7\u7684\u5217\u90fd\u76f8\u540c\uff0c\u5247\u8a72\u884c\u5c07\u88ab\u8996\u70ba\u91cd\u8907\u884c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-AlSvMXrbue\">\u7e3d\u7d50<\/h2>\n<p>\u4f7f\u7528DISTINCT\u95dc\u9375\u5b57\u53ef\u4ee5\u6709\u6548\u5730\u5f9eMySQL\u6578\u64da\u5eab\u4e2d\u63d0\u53d6\u552f\u4e00\u7684\u6578\u64da\uff0c\u9019\u5c0d\u65bc\u6578\u64da\u5206\u6790\u548c\u5831\u544a\u975e\u5e38\u91cd\u8981\u3002\u7121\u8ad6\u662f\u55ae\u5217\u9084\u662f\u591a\u5217\u67e5\u8a62\uff0cDISTINCT\u90fd\u80fd\u5e6b\u52a9\u6211\u5011\u7372\u5f97\u6240\u9700\u7684\u7d50\u679c\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u7528\u6236\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u5982<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u6216<a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a>\uff0c\u5c07\u6709\u52a9\u65bc\u63d0\u5347\u6574\u9ad4\u6027\u80fd\u548c\u6548\u7387\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u5728MySQL\u4e2d\u4f7f\u7528DISTINCT\u95dc\u9375\u5b57\uff0c\u8f15\u9b06\u7372\u53d6\u67e5\u8a62\u7d50\u679c\u4e2d\u7684\u552f\u4e00\u503c\uff0c\u63d0\u5347\u6578\u64da\u5206\u6790\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-76214","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76214","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=76214"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76214\/revisions"}],"predecessor-version":[{"id":76215,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/76214\/revisions\/76215"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=76214"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=76214"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=76214"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}