{"id":80549,"date":"2024-10-16T14:25:14","date_gmt":"2024-10-16T06:25:14","guid":{"rendered":"https:\/\/server.hk\/cnblog\/80549\/"},"modified":"2024-10-16T14:25:15","modified_gmt":"2024-10-16T06:25:15","slug":"mysql%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84%e7%9a%84%e8%99%95%e7%90%86%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/80549\/","title":{"rendered":"MySQL\u91cd\u8907\u8a18\u9304\u7684\u8655\u7406\u65b9\u6cd5"},"content":{"rendered":"<h1 id=\"mysql%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84%e7%9a%84%e8%99%95%e7%90%86%e6%96%b9%e6%b3%95-jszLsLAtCA\">MySQL\u91cd\u8907\u8a18\u9304\u7684\u8655\u7406\u65b9\u6cd5<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u8a18\u9304\u662f\u4e00\u500b\u5e38\u898b\u7684\u554f\u984c\uff0c\u7279\u5225\u662f\u5728\u4f7f\u7528MySQL\u6642\u3002\u91cd\u8907\u8a18\u9304\u4e0d\u50c5\u6703\u6d6a\u8cbb\u5b58\u5132\u7a7a\u9593\uff0c\u9084\u53ef\u80fd\u5c0e\u81f4\u6578\u64da\u4e0d\u4e00\u81f4\u6027\uff0c\u5f71\u97ff\u67e5\u8a62\u6027\u80fd\u3002\u56e0\u6b64\uff0c\u4e86\u89e3\u5982\u4f55\u6709\u6548\u5730\u8655\u7406MySQL\u4e2d\u7684\u91cd\u8907\u8a18\u9304\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002<\/p>\n<h2 id=\"%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84%e7%9a%84%e8%ad%98%e5%88%a5-jszLsLAtCA\">\u91cd\u8907\u8a18\u9304\u7684\u8b58\u5225<\/h2>\n<p>\u9996\u5148\uff0c\u70ba\u4e86\u8655\u7406\u91cd\u8907\u8a18\u9304\uff0c\u6211\u5011\u9700\u8981\u8b58\u5225\u5b83\u5011\u3002\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bSQL\u67e5\u8a62\u4f86\u67e5\u627e\u91cd\u8907\u7684\u8a18\u9304\uff1a<\/p>\n<pre><code>SELECT column_name, COUNT(*)\nFROM table_name\nGROUP BY column_name\nHAVING COUNT(*) &gt; 1;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c\u5c07<code>column_name<\/code>\u66ff\u63db\u70ba\u4f60\u60f3\u8981\u6aa2\u67e5\u7684\u5217\u540d\uff0c<code>table_name<\/code>\u66ff\u63db\u70ba\u4f60\u7684\u8868\u540d\u3002\u9019\u6a23\u53ef\u4ee5\u627e\u51fa\u6240\u6709\u91cd\u8907\u7684\u8a18\u9304\u53ca\u5176\u51fa\u73fe\u7684\u6b21\u6578\u3002<\/p>\n<h2 id=\"%e5%88%aa%e9%99%a4%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84-jszLsLAtCA\">\u522a\u9664\u91cd\u8907\u8a18\u9304<\/h2>\n<p>\u4e00\u65e6\u8b58\u5225\u51fa\u91cd\u8907\u8a18\u9304\uff0c\u63a5\u4e0b\u4f86\u7684\u6b65\u9a5f\u662f\u522a\u9664\u5b83\u5011\u3002\u4ee5\u4e0b\u662f\u5e7e\u7a2e\u5e38\u898b\u7684\u65b9\u6cd5\uff1a<\/p>\n<h3 id=\"%e6%96%b9%e6%b3%95%e4%b8%80%ef%bc%9a%e4%bd%bf%e7%94%a8delete%e8%aa%9e%e5%8f%a5-jszLsLAtCA\">\u65b9\u6cd5\u4e00\uff1a\u4f7f\u7528DELETE\u8a9e\u53e5<\/h3>\n<p>\u53ef\u4ee5\u4f7f\u7528DELETE\u8a9e\u53e5\u4f86\u522a\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n<pre><code>DELETE t1\nFROM table_name t1\nINNER JOIN table_name t2 \nWHERE \n    t1.id &gt; t2.id AND \n    t1.column_name = t2.column_name;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c<code>id<\/code>\u662f\u8868\u4e2d\u7684\u4e3b\u9375\uff0c\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u53ea\u4fdd\u7559\u4e00\u689d\u8a18\u9304\u3002<\/p>\n<h3 id=\"%e6%96%b9%e6%b3%95%e4%ba%8c%ef%bc%9a%e4%bd%bf%e7%94%a8cte%ef%bc%88%e5%85%ac%e7%94%a8%e8%a1%a8%e8%a1%a8%e9%81%94%e5%bc%8f%ef%bc%89-jszLsLAtCA\">\u65b9\u6cd5\u4e8c\uff1a\u4f7f\u7528CTE\uff08\u516c\u7528\u8868\u8868\u9054\u5f0f\uff09<\/h3>\n<p>\u5982\u679c\u4f60\u7684MySQL\u7248\u672c\u652f\u6301CTE\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\u4f86\u522a\u9664\u91cd\u8907\u8a18\u9304\uff1a<\/p>\n<pre><code>WITH CTE AS (\n    SELECT column_name, \n           ROW_NUMBER() OVER (PARTITION BY column_name ORDER BY id) AS row_num\n    FROM table_name\n)\nDELETE FROM CTE WHERE row_num &gt; 1;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u6703\u70ba\u6bcf\u7d44\u91cd\u8907\u7684\u8a18\u9304\u5206\u914d\u4e00\u500b\u884c\u865f\uff0c\u7136\u5f8c\u522a\u9664\u884c\u865f\u5927\u65bc1\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e9%98%b2%e6%ad%a2%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84%e7%9a%84%e6%8e%aa%e6%96%bd-jszLsLAtCA\">\u9632\u6b62\u91cd\u8907\u8a18\u9304\u7684\u63aa\u65bd<\/h2>\n<p>\u9664\u4e86\u522a\u9664\u91cd\u8907\u8a18\u9304\uff0c\u9084\u61c9\u8a72\u63a1\u53d6\u63aa\u65bd\u4f86\u9632\u6b62\u672a\u4f86\u51fa\u73fe\u91cd\u8907\u8a18\u9304\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5efa\u8b70\uff1a<\/p>\n<ul>\n<li><strong>\u8a2d\u7f6e\u552f\u4e00\u7d22\u5f15\uff1a<\/strong>\u5728\u9700\u8981\u4fdd\u6301\u552f\u4e00\u6027\u7684\u5217\u4e0a\u8a2d\u7f6e\u552f\u4e00\u7d22\u5f15\uff0c\u53ef\u4ee5\u6709\u6548\u9632\u6b62\u91cd\u8907\u8a18\u9304\u7684\u63d2\u5165\u3002<\/li>\n<li><strong>\u6578\u64da\u9a57\u8b49\uff1a<\/strong>\u5728\u61c9\u7528\u5c64\u9032\u884c\u6578\u64da\u9a57\u8b49\uff0c\u78ba\u4fdd\u5728\u63d2\u5165\u6578\u64da\u4e4b\u524d\u6aa2\u67e5\u662f\u5426\u5df2\u5b58\u5728\u76f8\u540c\u7684\u8a18\u9304\u3002<\/li>\n<li><strong>\u5b9a\u671f\u6e05\u7406\uff1a<\/strong>\u5b9a\u671f\u57f7\u884c\u6e05\u7406\u4efb\u52d9\uff0c\u6aa2\u67e5\u4e26\u522a\u9664\u91cd\u8907\u8a18\u9304\uff0c\u4ee5\u4fdd\u6301\u6578\u64da\u5eab\u7684\u6574\u6f54\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-jszLsLAtCA\">\u7e3d\u7d50<\/h2>\n<p>\u8655\u7406MySQL\u4e2d\u7684\u91cd\u8907\u8a18\u9304\u662f\u4e00\u500b\u91cd\u8981\u7684\u6578\u64da\u7ba1\u7406\u4efb\u52d9\u3002\u901a\u904e\u8b58\u5225\u3001\u522a\u9664\u548c\u9632\u6b62\u91cd\u8907\u8a18\u9304\uff0c\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u5eab\u7684\u6027\u80fd\u548c\u6578\u64da\u7684\u4e00\u81f4\u6027\u3002\u7121\u8ad6\u662f\u4f7f\u7528DELETE\u8a9e\u53e5\u9084\u662fCTE\uff0c\u9078\u64c7\u5408\u9069\u7684\u65b9\u6cd5\u4f86\u8655\u7406\u91cd\u8907\u8a18\u9304\u90fd\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u82e5\u60a8\u9700\u8981\u9032\u4e00\u6b65\u4e86\u89e3\u5982\u4f55\u512a\u5316\u60a8\u7684\u6578\u64da\u5eab\u6216\u5c0b\u627e\u5408\u9069\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u4fe1\u606f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22MySQL\u4e2d\u91cd\u8907\u8a18\u9304\u7684\u8655\u7406\u65b9\u6cd5\uff0c\u5305\u62ec\u67e5\u627e\u3001\u522a\u9664\u548c\u5408\u4f75\u91cd\u8907\u6578\u64da\u7684\u6709\u6548\u6280\u5de7\u8207\u6b65\u9a5f\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-80549","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/80549","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=80549"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/80549\/revisions"}],"predecessor-version":[{"id":80550,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/80549\/revisions\/80550"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=80549"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=80549"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=80549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}