{"id":141667,"date":"2024-10-31T21:56:20","date_gmt":"2024-10-31T13:56:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/141667\/"},"modified":"2024-10-31T21:56:21","modified_gmt":"2024-10-31T13:56:21","slug":"sql-server-%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e5%88%aa%e9%99%a4%e7%9a%84%e5%af%a6%e7%8f%be%e6%96%b9%e6%a1%88%e5%88%97%e8%88%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/141667\/","title":{"rendered":"SQL Server \u91cd\u8907\u6578\u64da\u522a\u9664\u7684\u5be6\u73fe\u65b9\u6848\u5217\u8209"},"content":{"rendered":"

SQL Server \u91cd\u8907\u6578\u64da\u522a\u9664\u7684\u5be6\u73fe\u65b9\u6848\u5217\u8209<\/h1>\n

\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u6578\u64da\u7684\u5b58\u5728\u6703\u5f71\u97ff\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u67e5\u8a62\u6548\u7387\u3002\u7279\u5225\u662f\u5728\u4f7f\u7528 SQL Server \u7684\u74b0\u5883\u4e2d\uff0c\u5982\u4f55\u6709\u6548\u5730\u8b58\u5225\u548c\u522a\u9664\u91cd\u8907\u6578\u64da\u6210\u70ba\u4e86\u4e00\u500b\u91cd\u8981\u7684\u8ab2\u984c\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5e7e\u7a2e\u5728 SQL Server \u4e2d\u5be6\u73fe\u91cd\u8907\u6578\u64da\u522a\u9664\u7684\u65b9\u6848\uff0c\u5e6b\u52a9\u6578\u64da\u5eab\u7ba1\u7406\u54e1\u66f4\u597d\u5730\u7dad\u8b77\u6578\u64da\u8cea\u91cf\u3002<\/p>\n

1. \u4f7f\u7528 ROW_NUMBER() \u51fd\u6578<\/h2>\n

ROW_NUMBER() \u51fd\u6578\u53ef\u4ee5\u70ba\u67e5\u8a62\u7d50\u679c\u4e2d\u7684\u6bcf\u4e00\u884c\u5206\u914d\u4e00\u500b\u552f\u4e00\u7684\u5e8f\u865f\uff0c\u9019\u4f7f\u5f97\u6211\u5011\u80fd\u5920\u8f15\u9b06\u8b58\u5225\u91cd\u8907\u7684\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff0c\u5c55\u793a\u5982\u4f55\u4f7f\u7528 ROW_NUMBER() \u522a\u9664\u91cd\u8907\u6578\u64da\uff1a<\/p>\n

WITH CTE AS (\n    SELECT \n        *,\n        ROW_NUMBER() OVER (PARTITION BY column1, column2 ORDER BY (SELECT NULL)) AS rn\n    FROM \n        your_table\n)\nDELETE FROM CTE WHERE rn > 1;<\/code><\/pre>\n
\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u6839\u64da column1 \u548c column2 \u7684\u503c\u4f86\u8b58\u5225\u91cd\u8907\u7684\u884c\uff0c\u4e26\u522a\u9664\u591a\u9918\u7684\u884c\uff0c\u53ea\u4fdd\u7559\u7b2c\u4e00\u884c\u3002<\/p>\n
2. \u4f7f\u7528 GROUP BY \u548c HAVING \u5b50\u53e5<\/h2>\n
\u53e6\u4e00\u7a2e\u5e38\u898b\u7684\u65b9\u6cd5\u662f\u4f7f\u7528 GROUP BY \u548c HAVING \u5b50\u53e5\u4f86\u8b58\u5225\u91cd\u8907\u7684\u6578\u64da\u3002\u9019\u7a2e\u65b9\u6cd5\u9069\u5408\u65bc\u9700\u8981\u9032\u884c\u805a\u5408\u64cd\u4f5c\u7684\u60c5\u6cc1\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n
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
\u5728\u9019\u88e1\uff0c\u6211\u5011\u901a\u904e GROUP BY \u5c0d column1 \u548c column2 \u9032\u884c\u5206\u7d44\uff0c\u4e26\u4f7f\u7528 MIN(id) \u4f86\u4fdd\u7559\u6bcf\u7d44\u4e2d\u7684\u7b2c\u4e00\u689d\u8a18\u9304\uff0c\u522a\u9664\u5176\u4ed6\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n
3. \u4f7f\u7528 DISTINCT \u95dc\u9375\u5b57<\/h2>\n
\u5982\u679c\u9700\u8981\u5275\u5efa\u4e00\u500b\u4e0d\u5305\u542b\u91cd\u8907\u6578\u64da\u7684\u65b0\u8868\uff0c\u53ef\u4ee5\u4f7f\u7528 DISTINCT \u95dc\u9375\u5b57\u3002\u9019\u7a2e\u65b9\u6cd5\u4e0d\u6703\u76f4\u63a5\u522a\u9664\u539f\u8868\u4e2d\u7684\u6578\u64da\uff0c\u800c\u662f\u5275\u5efa\u4e00\u500b\u65b0\u7684\u8868\u4f86\u5b58\u5132\u552f\u4e00\u7684\u8a18\u9304\uff1a<\/p>\n
SELECT DISTINCT *\nINTO new_table\nFROM your_table;<\/code><\/pre>\n
\u9019\u6a23\uff0c\u6211\u5011\u5c31\u53ef\u4ee5\u5728 new_table \u4e2d\u7372\u5f97\u4e0d\u5305\u542b\u91cd\u8907\u6578\u64da\u7684\u8a18\u9304\uff0c\u7136\u5f8c\u53ef\u4ee5\u6839\u64da\u9700\u8981\u9032\u884c\u9032\u4e00\u6b65\u7684\u8655\u7406\u3002<\/p>\n
4. \u4f7f\u7528\u81ea\u5b9a\u7fa9\u51fd\u6578<\/h2>\n
\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u53ef\u80fd\u9700\u8981\u66f4\u9748\u6d3b\u7684\u89e3\u6c7a\u65b9\u6848\u4f86\u8655\u7406\u91cd\u8907\u6578\u64da\u3002\u9019\u6642\u53ef\u4ee5\u8003\u616e\u5275\u5efa\u81ea\u5b9a\u7fa9\u51fd\u6578\u4f86\u6aa2\u67e5\u548c\u522a\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u793a\u4f8b\uff1a<\/p>\n
CREATE FUNCTION dbo.RemoveDuplicates()\nRETURNS TABLE\nAS\nRETURN (\n    SELECT \n        *\n    FROM \n        your_table\n    WHERE \n        id IN (\n            SELECT MIN(id)\n            FROM your_table\n            GROUP BY column1, column2\n        )\n);<\/code><\/pre>\n
\u9019\u500b\u51fd\u6578\u5c07\u8fd4\u56de\u4e00\u500b\u4e0d\u5305\u542b\u91cd\u8907\u6578\u64da\u7684\u7d50\u679c\u96c6\uff0c\u4f7f\u7528\u8005\u53ef\u4ee5\u6839\u64da\u9700\u8981\u9032\u884c\u8abf\u7528\u3002<\/p>\n
5. \u4f7f\u7528 SQL Server Management Studio (SSMS)<\/h2>\n
\u9664\u4e86\u4f7f\u7528 SQL \u8a9e\u53e5\uff0cSQL Server Management Studio (SSMS) \u4e5f\u63d0\u4f9b\u4e86\u5716\u5f62\u5316\u7684\u5de5\u5177\u4f86\u5e6b\u52a9\u7528\u6236\u8b58\u5225\u548c\u522a\u9664\u91cd\u8907\u6578\u64da\u3002\u7528\u6236\u53ef\u4ee5\u901a\u904e\u67e5\u8a62\u8a2d\u8a08\u5668\u4f86\u69cb\u5efa\u67e5\u8a62\uff0c\u4e26\u4f7f\u7528\u8996\u89ba\u5316\u7684\u65b9\u5f0f\u4f86\u67e5\u770b\u548c\u522a\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n
\u7e3d\u7d50<\/h2>\n
\u5728 SQL Server \u4e2d\uff0c\u91cd\u8907\u6578\u64da\u7684\u522a\u9664\u662f\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\u7684\u4e00\u500b\u91cd\u8981\u4efb\u52d9\u3002\u901a\u904e\u4f7f\u7528 ROW_NUMBER() \u51fd\u6578\u3001GROUP BY \u548c HAVING \u5b50\u53e5\u3001DISTINCT \u95dc\u9375\u5b57\u3001\u81ea\u5b9a\u7fa9\u51fd\u6578\u4ee5\u53ca SQL Server Management Studio \u7b49\u65b9\u6cd5\uff0c\u6578\u64da\u5eab\u7ba1\u7406\u54e1\u53ef\u4ee5\u6709\u6548\u5730\u8b58\u5225\u548c\u522a\u9664\u91cd\u8907\u6578\u64da\uff0c\u5f9e\u800c\u63d0\u9ad8\u6578\u64da\u7684\u8cea\u91cf\u548c\u67e5\u8a62\u6548\u7387\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u4f01\u696d\uff0c\u9078\u64c7\u5408\u9069\u7684 VPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4e5f\u662f\u81f3\u95dc\u91cd\u8981\u7684\uff0c\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u6578\u64da\u5eab\u7684\u7a69\u5b9a\u6027\u548c\u6027\u80fd\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u63a2\u7d22\u591a\u7a2eSQL Server\u91cd\u8907\u6578\u64da\u522a\u9664\u7684\u5be6\u73fe\u65b9\u6848\uff0c\u63d0\u5347\u6578\u64da\u8cea\u91cf\u8207\u67e5\u8a62\u6548\u7387\uff0c\u78ba\u4fdd\u6578\u64da\u5eab\u7684\u6574\u6f54\u8207\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-141667","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/141667","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=141667"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/141667\/revisions"}],"predecessor-version":[{"id":141668,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/141667\/revisions\/141668"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=141667"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=141667"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=141667"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}