{"id":174957,"date":"2024-11-08T01:11:19","date_gmt":"2024-11-07T17:11:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/174957\/"},"modified":"2024-11-08T01:11:20","modified_gmt":"2024-11-07T17:11:20","slug":"%e5%a6%82%e4%bd%95%e5%8e%bb%e9%99%a4%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8%e4%b8%ad%e7%9a%84%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a-%e5%8e%bb%e6%8e%89%e8%a1%a8%e4%b8%ad%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/174957\/","title":{"rendered":"\u5982\u4f55\u53bb\u9664\u6578\u64da\u5eab\u8868\u4e2d\u7684\u91cd\u8907\u6578\u64da (\u53bb\u6389\u8868\u4e2d\u91cd\u8907\u6578\u64da\u5eab)"},"content":{"rendered":"<h1 id=\"%e5%a6%82%e4%bd%95%e5%8e%bb%e9%99%a4%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8%e4%b8%ad%e7%9a%84%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a-%e5%8e%bb%e6%8e%89%e8%a1%a8%e4%b8%ad%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a-qtdgBticMI\">\u5982\u4f55\u53bb\u9664\u6578\u64da\u5eab\u8868\u4e2d\u7684\u91cd\u8907\u6578\u64da (\u53bb\u6389\u8868\u4e2d\u91cd\u8907\u6578\u64da\u5eab)<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u6578\u64da\u662f\u4e00\u500b\u5e38\u898b\u7684\u554f\u984c\uff0c\u9019\u4e0d\u50c5\u6703\u5f71\u97ff\u6578\u64da\u7684\u6e96\u78ba\u6027\uff0c\u9084\u6703\u5c0e\u81f4\u6027\u80fd\u4e0b\u964d\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u6709\u6548\u5730\u53bb\u9664\u6578\u64da\u5eab\u8868\u4e2d\u7684\u91cd\u8907\u6578\u64da\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u793a\u4f8b\u548c\u4ee3\u78bc\u7247\u6bb5\u3002<\/p>\n<h2 id=\"%e7%82%ba%e4%bb%80%e9%ba%bc%e9%9c%80%e8%a6%81%e5%8e%bb%e9%99%a4%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a-qtdgBticMI\">\u70ba\u4ec0\u9ebc\u9700\u8981\u53bb\u9664\u91cd\u8907\u6578\u64da<\/h2>\n<p>\u91cd\u8907\u6578\u64da\u53ef\u80fd\u6703\u5c0e\u81f4\u591a\u7a2e\u554f\u984c\uff0c\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u6578\u64da\u4e0d\u4e00\u81f4\u6027\uff1a\u76f8\u540c\u7684\u6578\u64da\u53ef\u80fd\u5728\u4e0d\u540c\u7684\u884c\u4e2d\u5b58\u5728\u4e0d\u540c\u7684\u503c\u3002<\/li>\n<li>\u6027\u80fd\u554f\u984c\uff1a\u67e5\u8a62\u548c\u64cd\u4f5c\u91cd\u8907\u6578\u64da\u6703\u589e\u52a0\u6578\u64da\u5eab\u7684\u8ca0\u64d4\uff0c\u5f71\u97ff\u6027\u80fd\u3002<\/li>\n<li>\u5b58\u5132\u6d6a\u8cbb\uff1a\u91cd\u8907\u6578\u64da\u6703\u4f54\u7528\u984d\u5916\u7684\u5b58\u5132\u7a7a\u9593\uff0c\u589e\u52a0\u7ba1\u7406\u6210\u672c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e8%ad%98%e5%88%a5%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a-qtdgBticMI\">\u8b58\u5225\u91cd\u8907\u6578\u64da<\/h2>\n<p>\u5728\u53bb\u9664\u91cd\u8907\u6578\u64da\u4e4b\u524d\uff0c\u9996\u5148\u9700\u8981\u8b58\u5225\u54ea\u4e9b\u6578\u64da\u662f\u91cd\u8907\u7684\u3002\u53ef\u4ee5\u4f7f\u7528 SQL \u67e5\u8a62\u4f86\u67e5\u627e\u91cd\u8907\u7684\u884c\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\u67e5\u8a62\uff0c\u8a72\u67e5\u8a62\u5c07\u8fd4\u56de\u91cd\u8907\u7684\u8a18\u9304\uff1a<\/p>\n<pre><code>SELECT column1, column2, COUNT(*)\nFROM your_table\nGROUP BY column1, column2\nHAVING COUNT(*) &gt; 1;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c`column1` \u548c `column2` \u662f\u4f60\u60f3\u8981\u6aa2\u67e5\u91cd\u8907\u7684\u5217\u3002`COUNT(*)` \u51fd\u6578\u7528\u65bc\u8a08\u7b97\u6bcf\u7d44\u7684\u884c\u6578\uff0c`HAVING` \u5b50\u53e5\u5247\u7528\u65bc\u904e\u6ffe\u51fa\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e5%8e%bb%e9%99%a4%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e7%9a%84%e6%96%b9%e6%b3%95-qtdgBticMI\">\u53bb\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6cd5<\/h2>\n<p>\u4e00\u65e6\u8b58\u5225\u51fa\u91cd\u8907\u6578\u64da\uff0c\u5c31\u53ef\u4ee5\u4f7f\u7528\u5e7e\u7a2e\u65b9\u6cd5\u4f86\u53bb\u9664\u5b83\u5011\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u65b9\u6cd5\uff1a<\/p>\n<h3 id=\"1-%e4%bd%bf%e7%94%a8-delete-%e8%aa%9e%e5%8f%a5-qtdgBticMI\">1. \u4f7f\u7528 DELETE \u8a9e\u53e5<\/h3>\n<p>\u53ef\u4ee5\u4f7f\u7528 DELETE \u8a9e\u53e5\u4f86\u522a\u9664\u91cd\u8907\u7684\u884c\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n<pre><code>DELETE FROM your_table\nWHERE id NOT IN (\n    SELECT MIN(id)\n    FROM your_table\n    GROUP BY column1, column2\n);<\/code><\/pre>\n<p>\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0c`id` \u662f\u8868\u4e2d\u7684\u4e3b\u9375\uff0c`MIN(id)` \u7528\u65bc\u4fdd\u7559\u6bcf\u7d44\u7684\u7b2c\u4e00\u689d\u8a18\u9304\uff0c\u5176\u4ed6\u7684\u5247\u88ab\u522a\u9664\u3002<\/p>\n<h3 id=\"2-%e4%bd%bf%e7%94%a8%e8%87%a8%e6%99%82%e8%a1%a8-qtdgBticMI\">2. \u4f7f\u7528\u81e8\u6642\u8868<\/h3>\n<p>\u53e6\u4e00\u7a2e\u65b9\u6cd5\u662f\u4f7f\u7528\u81e8\u6642\u8868\u4f86\u5b58\u5132\u552f\u4e00\u7684\u8a18\u9304\uff0c\u7136\u5f8c\u518d\u5c07\u5176\u63d2\u5165\u56de\u539f\u59cb\u8868\u4e2d\uff1a<\/p>\n<pre><code>CREATE TABLE temp_table AS\nSELECT DISTINCT *\nFROM your_table;\n\nDELETE FROM your_table;\n\nINSERT INTO your_table\nSELECT *\nFROM temp_table;\n\nDROP TABLE temp_table;<\/code><\/pre>\n<p>\u9019\u7a2e\u65b9\u6cd5\u7684\u512a\u9ede\u662f\u53ef\u4ee5\u4fdd\u7559\u6240\u6709\u552f\u4e00\u7684\u8a18\u9304\uff0c\u800c\u4e0d\u6703\u4e1f\u5931\u4efb\u4f55\u6578\u64da\u3002<\/p>\n<h3 id=\"3-%e4%bd%bf%e7%94%a8%e7%aa%97%e5%8f%a3%e5%87%bd%e6%95%b8-qtdgBticMI\">3. \u4f7f\u7528\u7a97\u53e3\u51fd\u6578<\/h3>\n<p>\u5728\u67d0\u4e9b\u6578\u64da\u5eab\u7cfb\u7d71\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528\u7a97\u53e3\u51fd\u6578\u4f86\u6a19\u8a18\u91cd\u8907\u7684\u884c\uff0c\u7136\u5f8c\u522a\u9664\u5b83\u5011\uff1a<\/p>\n<pre><code>WITH cte AS (\n    SELECT *,\n           ROW_NUMBER() OVER (PARTITION BY column1, column2 ORDER BY id) AS row_num\n    FROM your_table\n)\nDELETE FROM cte\nWHERE row_num &gt; 1;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u4f7f\u7528\u4e86 CTE\uff08\u516c\u5171\u8868\u8868\u9054\u5f0f\uff09\u548c\u7a97\u53e3\u51fd\u6578 `ROW_NUMBER()` \u4f86\u6a19\u8a18\u6bcf\u7d44\u7684\u884c\uff0c\u7136\u5f8c\u522a\u9664\u591a\u9918\u7684\u884c\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-qtdgBticMI\">\u7e3d\u7d50<\/h2>\n<p>\u53bb\u9664\u6578\u64da\u5eab\u8868\u4e2d\u7684\u91cd\u8907\u6578\u64da\u662f\u4e00\u500b\u91cd\u8981\u7684\u6578\u64da\u7ba1\u7406\u4efb\u52d9\uff0c\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u7684\u6e96\u78ba\u6027\u548c\u6027\u80fd\u3002\u901a\u904e\u4f7f\u7528 SQL \u67e5\u8a62\u4f86\u8b58\u5225\u548c\u522a\u9664\u91cd\u8907\u6578\u64da\uff0c\u60a8\u53ef\u4ee5\u78ba\u4fdd\u6578\u64da\u5eab\u7684\u6574\u6f54\u548c\u9ad8\u6548\u904b\u884c\u3002\u7121\u8ad6\u662f\u4f7f\u7528 DELETE \u8a9e\u53e5\u3001\u81e8\u6642\u8868\u9084\u662f\u7a97\u53e3\u51fd\u6578\uff0c\u9078\u64c7\u5408\u9069\u7684\u65b9\u6cd5\u5c07\u6709\u52a9\u65bc\u7c21\u5316\u6578\u64da\u7ba1\u7406\u6d41\u7a0b\u3002<\/p>\n<p>\u5982\u679c\u60a8\u9700\u8981\u66f4\u591a\u6709\u95dc <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u548c\u6578\u64da\u5eab\u7ba1\u7406\u7684\u8cc7\u8a0a\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u8cc7\u6e90\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2\u5982\u4f55\u6709\u6548\u53bb\u9664\u6578\u64da\u5eab\u8868\u4e2d\u7684\u91cd\u8907\u6578\u64da\uff0c\u63d0\u5347\u6578\u64da\u8cea\u91cf\uff0c\u512a\u5316\u67e5\u8a62\u6027\u80fd\uff0c\u78ba\u4fdd\u6578\u64da\u6e96\u78ba\u6027\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-174957","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/174957","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=174957"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/174957\/revisions"}],"predecessor-version":[{"id":174958,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/174957\/revisions\/174958"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=174957"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=174957"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=174957"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}