{"id":141665,"date":"2024-10-31T21:55:29","date_gmt":"2024-10-31T13:55:29","guid":{"rendered":"https:\/\/server.hk\/cnblog\/141665\/"},"modified":"2024-10-31T21:55:30","modified_gmt":"2024-10-31T13:55:30","slug":"sql-server-%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e5%88%aa%e9%99%a4%e7%9a%84-2-%e5%80%8b%e6%96%b9%e6%a1%88","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/141665\/","title":{"rendered":"SQL Server \u91cd\u8907\u6578\u64da\u522a\u9664\u7684 2 \u500b\u65b9\u6848"},"content":{"rendered":"<h1 id=\"sql-server-%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e5%88%aa%e9%99%a4%e7%9a%84-2-%e5%80%8b%e6%96%b9%e6%a1%88-WbzplvWydj\">SQL Server \u91cd\u8907\u6578\u64da\u522a\u9664\u7684 2 \u500b\u65b9\u6848<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u6578\u64da\u7684\u5b58\u5728\u4e0d\u50c5\u6703\u4f54\u7528\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\u53ca\u6642\u522a\u9664\u91cd\u8907\u6578\u64da\u662f\u7dad\u8b77\u6578\u64da\u5eab\u5065\u5eb7\u7684\u91cd\u8981\u6b65\u9a5f\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u5169\u7a2e\u5728 SQL Server \u4e2d\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6848\uff0c\u5e6b\u52a9\u7528\u6236\u6709\u6548\u7ba1\u7406\u6578\u64da\u3002<\/p>\n<h2 id=\"%e6%96%b9%e6%a1%88%e4%b8%80%ef%bc%9a%e4%bd%bf%e7%94%a8-cte%ef%bc%88%e5%85%ac%e7%94%a8%e8%a1%a8%e9%81%94%e5%bc%8f%ef%bc%89%e5%92%8c-row_number-WbzplvWydj\">\u65b9\u6848\u4e00\uff1a\u4f7f\u7528 CTE\uff08\u516c\u7528\u8868\u9054\u5f0f\uff09\u548c ROW_NUMBER()<\/h2>\n<p>\u4f7f\u7528 CTE \u548c ROW_NUMBER() \u51fd\u6578\u662f\u4e00\u7a2e\u5e38\u898b\u7684\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6cd5\u3002\u9019\u7a2e\u65b9\u6cd5\u7684\u57fa\u672c\u601d\u8def\u662f\u70ba\u6bcf\u4e00\u7d44\u91cd\u8907\u7684\u8a18\u9304\u5206\u914d\u4e00\u500b\u552f\u4e00\u7684\u884c\u865f\uff0c\u7136\u5f8c\u6839\u64da\u884c\u865f\u4f86\u522a\u9664\u591a\u9918\u7684\u8a18\u9304\u3002<\/p>\n<h3 id=\"%e6%ad%a5%e9%a9%9f%ef%bc%9a-WbzplvWydj\">\u6b65\u9a5f\uff1a<\/h3>\n<ol>\n<li>\u9996\u5148\uff0c\u4f7f\u7528 CTE \u4f86\u9078\u64c7\u9700\u8981\u522a\u9664\u7684\u91cd\u8907\u6578\u64da\u3002<\/li>\n<li>\u7136\u5f8c\uff0c\u6839\u64da\u67d0\u500b\u5b57\u6bb5\uff08\u5982 ID \u6216\u5176\u4ed6\u552f\u4e00\u6a19\u8b58\uff09\u70ba\u6bcf\u7d44\u91cd\u8907\u6578\u64da\u5206\u914d\u884c\u865f\u3002<\/li>\n<li>\u6700\u5f8c\uff0c\u522a\u9664\u884c\u865f\u5927\u65bc 1 \u7684\u8a18\u9304\u3002<\/li>\n<\/ol>\n<h3 id=\"%e7%a4%ba%e4%be%8b%e4%bb%a3%e7%a2%bc%ef%bc%9a-WbzplvWydj\">\u793a\u4f8b\u4ee3\u78bc\uff1a<\/h3>\n<pre><code>\nWITH CTE AS (\n    SELECT \n        *,\n        ROW_NUMBER() OVER (PARTITION BY column1, column2 ORDER BY (SELECT NULL)) AS row_num\n    FROM \n        your_table\n)\nDELETE FROM CTE WHERE row_num &gt; 1;\n<\/code><\/pre>\n<p>\u5728\u9019\u6bb5\u4ee3\u78bc\u4e2d\uff0c`column1` \u548c `column2` \u662f\u7528\u4f86\u5224\u65b7\u91cd\u8907\u7684\u5b57\u6bb5\u3002`ROW_NUMBER()` \u51fd\u6578\u6703\u70ba\u6bcf\u7d44\u91cd\u8907\u7684\u8a18\u9304\u5206\u914d\u4e00\u500b\u884c\u865f\uff0c\u7136\u5f8c\u901a\u904e\u522a\u9664\u884c\u865f\u5927\u65bc 1 \u7684\u8a18\u9304\u4f86\u5be6\u73fe\u91cd\u8907\u6578\u64da\u7684\u522a\u9664\u3002<\/p>\n<h2 id=\"%e6%96%b9%e6%a1%88%e4%ba%8c%ef%bc%9a%e4%bd%bf%e7%94%a8-group-by-%e5%92%8c-having-%e5%ad%90%e5%8f%a5-WbzplvWydj\">\u65b9\u6848\u4e8c\uff1a\u4f7f\u7528 GROUP BY \u548c HAVING \u5b50\u53e5<\/h2>\n<p>\u53e6\u4e00\u7a2e\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6cd5\u662f\u4f7f\u7528 GROUP BY \u548c HAVING \u5b50\u53e5\u3002\u9019\u7a2e\u65b9\u6cd5\u9069\u5408\u65bc\u9700\u8981\u6839\u64da\u67d0\u4e9b\u689d\u4ef6\u4f86\u7be9\u9078\u91cd\u8907\u6578\u64da\u7684\u60c5\u6cc1\u3002<\/p>\n<h3 id=\"%e6%ad%a5%e9%a9%9f%ef%bc%9a-WbzplvWydj\">\u6b65\u9a5f\uff1a<\/h3>\n<ol>\n<li>\u4f7f\u7528 GROUP BY \u5b50\u53e5\u4f86\u5206\u7d44\u91cd\u8907\u7684\u8a18\u9304\u3002<\/li>\n<li>\u4f7f\u7528 HAVING \u5b50\u53e5\u4f86\u7be9\u9078\u51fa\u91cd\u8907\u7684\u8a18\u9304\u3002<\/li>\n<li>\u6839\u64da\u7be9\u9078\u7d50\u679c\u522a\u9664\u591a\u9918\u7684\u8a18\u9304\u3002<\/li>\n<\/ol>\n<h3 id=\"%e7%a4%ba%e4%be%8b%e4%bb%a3%e7%a2%bc%ef%bc%9a-WbzplvWydj\">\u793a\u4f8b\u4ee3\u78bc\uff1a<\/h3>\n<pre><code>\nDELETE FROM your_table\nWHERE ID NOT IN (\n    SELECT MIN(ID)\n    FROM your_table\n    GROUP BY column1, column2\n);\n<\/code><\/pre>\n<p>\u5728\u9019\u6bb5\u4ee3\u78bc\u4e2d\uff0c`ID` \u662f\u6bcf\u689d\u8a18\u9304\u7684\u552f\u4e00\u6a19\u8b58\uff0c`column1` \u548c `column2` \u662f\u7528\u4f86\u5224\u65b7\u91cd\u8907\u7684\u5b57\u6bb5\u3002\u9019\u6bb5\u4ee3\u78bc\u6703\u4fdd\u7559\u6bcf\u7d44\u91cd\u8907\u8a18\u9304\u4e2d ID \u6700\u5c0f\u7684\u90a3\u4e00\u689d\uff0c\u4e26\u522a\u9664\u5176\u4ed6\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-WbzplvWydj\">\u7e3d\u7d50<\/h2>\n<p>\u5728 SQL Server \u4e2d\uff0c\u522a\u9664\u91cd\u8907\u6578\u64da\u662f\u6578\u64da\u5eab\u7ba1\u7406\u7684\u91cd\u8981\u4efb\u52d9\u3002\u672c\u6587\u4ecb\u7d39\u7684\u5169\u7a2e\u65b9\u6848\uff0c\u5206\u5225\u662f\u4f7f\u7528 CTE \u548c ROW_NUMBER() \u51fd\u6578\uff0c\u4ee5\u53ca\u4f7f\u7528 GROUP BY \u548c HAVING \u5b50\u53e5\uff0c\u90fd\u662f\u6709\u6548\u7684\u89e3\u6c7a\u65b9\u6848\u3002\u6839\u64da\u5177\u9ad4\u7684\u9700\u6c42\u548c\u6578\u64da\u7d50\u69cb\uff0c\u7528\u6236\u53ef\u4ee5\u9078\u64c7\u6700\u9069\u5408\u7684\u65b9\u6cd5\u4f86\u6e05\u7406\u6578\u64da\u3002<\/p>\n<p>\u5982\u679c\u60a8\u9700\u8981\u66f4\u9ad8\u6548\u7684\u6578\u64da\u7ba1\u7406\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u670d\u52d9\uff0c\u9019\u5c07\u70ba\u60a8\u7684\u6578\u64da\u5eab\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u548c\u9748\u6d3b\u7684\u64f4\u5c55\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22 SQL Server \u4e2d\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u5169\u7a2e\u6709\u6548\u65b9\u6848\uff0c\u63d0\u5347\u6578\u64da\u8cea\u91cf\u8207\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-141665","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/141665","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=141665"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/141665\/revisions"}],"predecessor-version":[{"id":141666,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/141665\/revisions\/141666"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=141665"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=141665"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=141665"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}