{"id":199662,"date":"2025-05-06T10:03:01","date_gmt":"2025-05-06T02:03:01","guid":{"rendered":"https:\/\/server.hk\/cnblog\/199662\/"},"modified":"2025-05-06T10:03:01","modified_gmt":"2025-05-06T02:03:01","slug":"%e6%b7%b1%e5%85%a5%e8%a7%a3%e6%9e%90sql%e4%b8%ad%e7%9a%84distinct%e5%85%b3%e9%94%ae%e5%ad%97","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/199662\/","title":{"rendered":"\u6df1\u5165\u89e3\u6790SQL\u4e2d\u7684DISTINCT\u5173\u952e\u5b57"},"content":{"rendered":"

<\/b> <\/p>\n

\u6df1\u5165\u89e3\u6790SQL\u4e2d\u7684DISTINCT\u5173\u952e\u5b57<\/h1>\n

\u4e00\u5206\u8015\u8018\uff0c\u4e00\u5206\u6536\u83b7\uff01\u65e2\u7136\u6253\u5f00\u4e86\u8fd9\u7bc7\u6587\u7ae0\uff0c\u5c31\u575a\u6301\u770b\u4e0b\u53bb\u5427\uff01\u6587\u4e2d\u5185\u5bb9\u5305\u542b\u7b49\u7b49\u77e5\u8bc6\u70b9…\u5e0c\u671b\u4f60\u80fd\u5728\u9605\u8bfb\u672c\u6587\u540e\uff0c\u80fd\u771f\u771f\u5b9e\u5b9e\u5b66\u5230\u77e5\u8bc6\u6216\u8005\u5e2e\u4f60\u89e3\u51b3\u5fc3\u4e2d\u7684\u7591\u60d1\uff0c\u4e5f\u6b22\u8fce\u5927\u4f6c\u6216\u8005\u65b0\u4eba\u670b\u53cb\u4eec\u591a\u7559\u8a00\u8bc4\u8bba\uff0c\u591a\u7ed9\u5efa\u8bae\uff01\u8c22\u8c22\uff01<\/p>\n

SQL\u4e2ddistinct\u7528\u6cd5\u8be6\u89e3<\/p>\n

\u5728SQL\u6570\u636e\u5e93\u4e2d\uff0c\u6211\u4eec\u7ecf\u5e38\u4f1a\u9047\u5230\u9700\u8981\u53bb\u9664\u91cd\u590d\u6570\u636e\u7684\u60c5\u51b5\u3002\u6b64\u65f6\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528distinct\u5173\u952e\u5b57\uff0c\u5b83\u80fd\u591f\u5e2e\u52a9\u6211\u4eec\u53bb\u9664\u91cd\u590d\u6570\u636e\uff0c\u4f7f\u5f97\u67e5\u8be2\u7ed3\u679c\u66f4\u52a0\u6e05\u6670\u548c\u51c6\u786e\u3002<\/p>\n

distinct\u7684\u57fa\u672c\u4f7f\u7528\u65b9\u6cd5\u975e\u5e38\u7b80\u5355\uff0c\u53ea\u9700\u8981\u5728select\u8bed\u53e5\u4e2d\u4f7f\u7528distinct\u5173\u952e\u5b57\u5373\u53ef\u3002\u4f8b\u5982\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e2a\u666e\u901a\u7684select\u8bed\u53e5\uff1a<\/p>\n

SELECT column_name FROM table_name;<\/pre>\n
\u5982\u679c\u6211\u4eec\u60f3\u8981\u53bb\u9664\u91cd\u590d\u6570\u636e\uff0c\u5728column_name\u524d\u9762\u52a0\u4e0adistinct\u5173\u952e\u5b57\u5373\u53ef\uff1a<\/p>\n
SELECT DISTINCT column_name FROM table_name;<\/pre>\n
distinct\u5173\u952e\u5b57\u5c06\u4f1a\u5bf9column_name\u7684\u6570\u636e\u8fdb\u884c\u53bb\u91cd\uff0c\u5e76\u5c06\u53bb\u91cd\u540e\u7684\u7ed3\u679c\u8fd4\u56de\u3002<\/p>\n
distinct\u5173\u952e\u5b57\u4e0d\u4ec5\u53ef\u4ee5\u7528\u4e8e\u5355\u5217\u6570\u636e\u7684\u53bb\u91cd\uff0c\u8fd8\u53ef\u4ee5\u7528\u4e8e\u591a\u5217\u6570\u636e\u7684\u53bb\u91cd\u3002\u4f8b\u5982\uff0c\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u8868\u683c\u540d\u4e3aorders\uff0c\u5305\u542b\u4e86\u8ba2\u5355\u53f7\uff08order_id\uff09\u548c\u5ba2\u6237\u540d\uff08customer_name\uff09\u4e24\u4e2a\u5b57\u6bb5\uff0c\u6211\u4eec\u60f3\u8981\u53bb\u9664\u91cd\u590d\u7684\u8ba2\u5355\u53f7\u548c\u5ba2\u6237\u540d\uff0c\u5219\u53ef\u4ee5\u4f7f\u7528\u5982\u4e0b\u7684\u67e5\u8be2\u8bed\u53e5\uff1a<\/p>\n
SELECT DISTINCT order_id, customer_name FROM orders;<\/pre>\n
\u4ee5\u4e0a\u8bed\u53e5\u5c06\u4f1a\u8fd4\u56de\u53bb\u9664\u91cd\u590d\u8ba2\u5355\u53f7\u548c\u5ba2\u6237\u540d\u540e\u7684\u7ed3\u679c\u96c6\u3002<\/p>\n
\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0cdistinct\u5173\u952e\u5b57\u662f\u9002\u7528\u4e8e\u6574\u4e2a\u7ed3\u679c\u96c6\uff0c\u800c\u4e0d\u4ec5\u4ec5\u662f\u5355\u4e2a\u5217\u3002\u4e5f\u5c31\u662f\u8bf4\uff0c\u5b83\u4f1a\u53bb\u9664\u6574\u4e2a\u7ed3\u679c\u96c6\u4e2d\u7684\u91cd\u590d\u884c\u3002\u56e0\u6b64\uff0c\u5728\u4f7f\u7528distinct\u5173\u952e\u5b57\u65f6\uff0c\u6211\u4eec\u9700\u8981\u786e\u4fdd\u88ab\u6bd4\u8f83\u7684\u6570\u636e\u96c6\u662f\u4e00\u81f4\u7684\u3002\u4f8b\u5982\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e2a\u9519\u8bef\u7684\u67e5\u8be2\u8bed\u53e5\uff1a<\/p>\n
SELECT DISTINCT column_name1, column_name2 FROM table_name;<\/pre>\n
\u4ee5\u4e0a\u67e5\u8be2\u8bed\u53e5\u662f\u9519\u8bef\u7684\uff0c\u56e0\u4e3a\u5728\u6bd4\u8f83\u4e24\u4e2a\u5217\u65f6\uff0c\u5fc5\u987b\u540c\u65f6\u8003\u8651\u4e24\u4e2a\u5217\u7684\u503c\uff0c\u5e76\u53bb\u9664\u91cd\u590d\u7684\u884c\u3002\u5426\u5219\uff0c\u5c06\u65e0\u6cd5\u8fbe\u5230\u53bb\u91cd\u7684\u6548\u679c\u3002<\/p>\n
\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u53ef\u80fd\u4f1a\u9047\u5230\u9700\u8981\u5bf9\u5217\u8fdb\u884c\u6392\u5e8f\u7684\u60c5\u51b5\u3002distinct\u5173\u952e\u5b57\u53ef\u4ee5\u4e0eorder by\u5b50\u53e5\u4e00\u8d77\u4f7f\u7528\uff0c\u4ee5\u5b9e\u73b0\u6309\u7279\u5b9a\u987a\u5e8f\u53bb\u9664\u91cd\u590d\u6570\u636e\u3002\u4f8b\u5982\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a<\/p>\n
SELECT DISTINCT column_name FROM table_name ORDER BY column_name ASC\/DESC;<\/pre>\n
\u4ee5\u4e0a\u8bed\u53e5\u5c06\u4f1a\u8fd4\u56de\u6309column_name\u5217\u8fdb\u884c\u6392\u5e8f\u540e\u7684\u53bb\u91cd\u7ed3\u679c\u96c6\u3002ASC\u8868\u793a\u5347\u5e8f\uff0cDESC\u8868\u793a\u964d\u5e8f\u3002<\/p>\n
\u9664\u4e86\u57fa\u672c\u7684distinct\u7528\u6cd5\u5916\uff0c\u6211\u4eec\u8fd8\u53ef\u4ee5\u4f7f\u7528distinct\u5173\u952e\u5b57\u6765\u8fdb\u884c\u4e00\u4e9b\u5176\u4ed6\u7684\u8fd0\u7b97\u64cd\u4f5c\u3002\u4f8b\u5982\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528count\u51fd\u6570\u6765\u7edf\u8ba1distinct\u5173\u952e\u5b57\u53bb\u91cd\u540e\u7684\u7ed3\u679c\u884c\u6570\u3002\u4f8b\u5982\uff1a<\/p>\n
SELECT COUNT(DISTINCT column_name) FROM table_name;<\/pre>\n
\u4ee5\u4e0a\u8bed\u53e5\u5c06\u4f1a\u8fd4\u56de\u53bb\u91cd\u540e\u7684\u7ed3\u679c\u96c6\u4e2d\u4e0d\u91cd\u590d\u884c\u7684\u6570\u91cf\u3002<\/p>\n
\u5728\u5b9e\u9645\u4f7f\u7528\u4e2d\uff0c\u6211\u4eec\u8fd8\u53ef\u4ee5\u7ed3\u5408distinct\u5173\u952e\u5b57\u4f7f\u7528\u5176\u4ed6SQL\u64cd\u4f5c\uff0c\u5982\u8868\u7684\u8054\u7ed3\u3001\u5b50\u67e5\u8be2\u3001\u6761\u4ef6\u8fc7\u6ee4\u7b49\u3002\u4f8b\u5982\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e2a\u7ed3\u5408distinct\u548c\u5b50\u67e5\u8be2\u7684\u793a\u4f8b\uff1a<\/p>\n
SELECT DISTINCT column_name FROM table_name WHERE column_name IN (SELECT column_name FROM table_name WHERE condition);<\/pre>\n
\u4ee5\u4e0a\u8bed\u53e5\u5c06\u4f1a\u8fd4\u56de\u6ee1\u8db3\u6761\u4ef6\u7684\u4e0d\u91cd\u590d\u7684column_name\u503c\u3002<\/p>\n
\u7efc\u4e0a\u6240\u8ff0\uff0cdistinct\u5173\u952e\u5b57\u662fSQL\u4e2d\u5e38\u7528\u7684\u4e00\u4e2a\u5173\u952e\u5b57\uff0c\u7528\u4e8e\u5bf9\u67e5\u8be2\u7ed3\u679c\u8fdb\u884c\u53bb\u91cd\u64cd\u4f5c\u3002\u901a\u8fc7\u53bb\u9664\u91cd\u590d\u6570\u636e\uff0c\u6211\u4eec\u80fd\u591f\u5f97\u5230\u66f4\u6e05\u6670\u548c\u51c6\u786e\u7684\u7ed3\u679c\u96c6\u3002\u5728\u4f7f\u7528distinct\u65f6\uff0c\u9700\u8981\u6ce8\u610f\u88ab\u6bd4\u8f83\u7684\u5217\u6216\u7ec4\u5408\u9700\u8981\u4fdd\u6301\u4e00\u81f4\uff0c\u540c\u65f6\u8fd8\u53ef\u4ee5\u7ed3\u5408\u5176\u4ed6SQL\u64cd\u4f5c\u8fdb\u884c\u66f4\u590d\u6742\u7684\u67e5\u8be2\u7ed3\u679c\u5904\u7406\u3002\u5e0c\u671b\u672c\u6587\u80fd\u591f\u5bf9distinct\u7528\u6cd5\u6709\u4e00\u4e2a\u66f4\u8be6\u7ec6\u7684\u4e86\u89e3\u3002<\/p>\n
\u4ee5\u4e0a\u5c31\u662f\u672c\u6587\u7684\u5168\u90e8\u5185\u5bb9\u4e86\uff0c\u662f\u5426\u6709\u987a\u5229\u5e2e\u52a9\u4f60\u89e3\u51b3\u95ee\u9898\uff1f\u82e5\u662f\u80fd\u7ed9\u4f60\u5e26\u6765\u5b66\u4e60\u4e0a\u7684\u5e2e\u52a9\uff0c\u8bf7\u5927\u5bb6\u591a\u591a\u652f\u6301\u4e3b\u673a\u5b9d\u8d1d\uff01\u66f4\u591a\u5173\u4e8e\u6570\u636e\u5e93\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u4e5f\u53ef\u5173\u6ce8\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\u3002<\/p>\n
\n
\n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"
\u6df1\u5165\u89e3\u6790SQL\u4e2d\u7684DISTINC...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-199662","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199662","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"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=199662"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199662\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=199662"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=199662"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=199662"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}