{"id":139043,"date":"2024-10-31T17:46:31","date_gmt":"2024-10-31T09:46:31","guid":{"rendered":"https:\/\/server.hk\/cnblog\/139043\/"},"modified":"2024-10-31T17:46:32","modified_gmt":"2024-10-31T09:46:32","slug":"sql-server%e5%88%aa%e9%99%a4%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%e7%9a%84%e6%96%b9%e6%a1%88%e6%9c%89%e5%93%aa%e4%ba%9b%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/139043\/","title":{"rendered":"SQL Server\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6848\u6709\u54ea\u4e9b\uff1f"},"content":{"rendered":"

SQL Server\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6848\u6709\u54ea\u4e9b\uff1f<\/h1>\n

\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u6578\u64da\u662f\u4e00\u500b\u5e38\u898b\u7684\u554f\u984c\uff0c\u7279\u5225\u662f\u5728\u4f7f\u7528SQL Server\u6642\u3002\u91cd\u8907\u6578\u64da\u4e0d\u50c5\u6703\u4f54\u7528\u5b58\u5132\u7a7a\u9593\uff0c\u9084\u53ef\u80fd\u5c0e\u81f4\u67e5\u8a62\u7d50\u679c\u4e0d\u6e96\u78ba\uff0c\u5f71\u97ff\u6578\u64da\u5206\u6790\u7684\u7d50\u679c\u3002\u56e0\u6b64\uff0c\u4e86\u89e3\u5982\u4f55\u6709\u6548\u5730\u522a\u9664\u91cd\u8907\u6578\u64da\u662f\u6bcf\u4f4d\u6578\u64da\u5eab\u7ba1\u7406\u54e1\u5fc5\u9808\u638c\u63e1\u7684\u6280\u80fd\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5e7e\u7a2e\u5728SQL Server\u4e2d\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6848\u3002<\/p>\n

1. \u4f7f\u7528CTE\uff08\u516c\u7528\u8868\u8868\u9054\u5f0f\uff09<\/h2>\n

\u516c\u7528\u8868\u8868\u9054\u5f0f\uff08CTE\uff09\u662f\u4e00\u7a2e\u81e8\u6642\u7d50\u679c\u96c6\uff0c\u53ef\u4ee5\u5728SELECT\u3001INSERT\u3001UPDATE\u6216DELETE\u8a9e\u53e5\u4e2d\u4f7f\u7528\u3002\u4f7f\u7528CTE\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u57fa\u672c\u6b65\u9a5f\u5982\u4e0b\uff1a<\/p>\n

WITH 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 > 1;<\/code><\/pre>\n
\u5728\u9019\u6bb5\u4ee3\u78bc\u4e2d\uff0cROW_NUMBER()<\/code>\u51fd\u6578\u70ba\u6bcf\u7d44\u91cd\u8907\u7684\u884c\u5206\u914d\u4e00\u500b\u552f\u4e00\u7684\u5e8f\u865f\uff0c\u7136\u5f8c\u522a\u9664\u5e8f\u865f\u5927\u65bc1\u7684\u884c\uff0c\u5f9e\u800c\u4fdd\u7559\u6bcf\u7d44\u7684\u7b2c\u4e00\u884c\u3002<\/p>\n
2. \u4f7f\u7528GROUP BY\u548cHAVING\u5b50\u53e5<\/h2>\n
\u53e6\u4e00\u7a2e\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6cd5\u662f\u4f7f\u7528GROUP BY<\/code>\u548cHAVING<\/code>\u5b50\u53e5\u3002\u9019\u7a2e\u65b9\u6cd5\u901a\u5e38\u7528\u65bc\u9700\u8981\u4fdd\u7559\u67d0\u4e9b\u805a\u5408\u6578\u64da\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\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u4f7f\u7528MIN(id)<\/code>\u4f86\u4fdd\u7559\u6bcf\u7d44\u91cd\u8907\u6578\u64da\u4e2d\u7684\u6700\u5c0fID\uff0c\u4e26\u522a\u9664\u5176\u4ed6\u91cd\u8907\u7684\u884c\u3002<\/p>\n
3. \u4f7f\u7528TEMP TABLE\uff08\u81e8\u6642\u8868\uff09<\/h2>\n
\u4f7f\u7528\u81e8\u6642\u8868\u4e5f\u662f\u4e00\u7a2e\u6709\u6548\u7684\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6cd5\u3002\u9019\u7a2e\u65b9\u6cd5\u7684\u6b65\u9a5f\u5982\u4e0b\uff1a<\/p>\n
SELECT DISTINCT *\nINTO #TempTable\nFROM your_table;\n\nDELETE FROM your_table;\n\nINSERT INTO your_table\nSELECT *\nFROM #TempTable;\n\nDROP TABLE #TempTable;<\/code><\/pre>\n
\u9019\u6bb5\u4ee3\u78bc\u9996\u5148\u5c07\u4e0d\u91cd\u8907\u7684\u6578\u64da\u63d2\u5165\u5230\u81e8\u6642\u8868\u4e2d\uff0c\u7136\u5f8c\u6e05\u7a7a\u539f\u59cb\u8868\uff0c\u6700\u5f8c\u5c07\u81e8\u6642\u8868\u4e2d\u7684\u6578\u64da\u63d2\u5165\u56de\u539f\u59cb\u8868\u3002\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u539f\u59cb\u8868\u4e2d\u4e0d\u6703\u6709\u91cd\u8907\u7684\u6578\u64da\u3002<\/p>\n
4. \u4f7f\u7528DELETE JOIN<\/h2>\n
\u4f7f\u7528JOIN\u8a9e\u53e5\u4e5f\u53ef\u4ee5\u522a\u9664\u91cd\u8907\u6578\u64da\u3002\u9019\u7a2e\u65b9\u6cd5\u7684\u57fa\u672c\u601d\u8def\u662f\u5c07\u91cd\u8907\u7684\u884c\u8207\u539f\u59cb\u8868\u9032\u884c\u9023\u63a5\uff0c\u7136\u5f8c\u522a\u9664\u91cd\u8907\u7684\u884c\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n
DELETE t1\nFROM your_table t1\nINNER JOIN your_table t2 \nON t1.column1 = t2.column1 AND t1.column2 = t2.column2\nWHERE t1.id > t2.id;<\/code><\/pre>\n
\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u901a\u904e\u6bd4\u8f03ID\u4f86\u78ba\u5b9a\u8981\u522a\u9664\u7684\u91cd\u8907\u884c\uff0c\u4fdd\u7559ID\u8f03\u5c0f\u7684\u884c\u3002<\/p>\n
5. \u4f7f\u7528SQL Server\u7684\u5167\u5efa\u529f\u80fd<\/h2>\n
SQL Server\u9084\u63d0\u4f9b\u4e86\u4e00\u4e9b\u5167\u5efa\u7684\u529f\u80fd\u4f86\u5e6b\u52a9\u7ba1\u7406\u91cd\u8907\u6578\u64da\u3002\u4f8b\u5982\uff0c\u53ef\u4ee5\u4f7f\u7528MERGE<\/code>\u8a9e\u53e5\u4f86\u5408\u4f75\u6578\u64da\uff0c\u9019\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\u4e5f\u53ef\u4ee5\u7528\u4f86\u522a\u9664\u91cd\u8907\u6578\u64da\u3002<\/p>\n
MERGE INTO target_table AS target\nUSING source_table AS source\nON target.column1 = source.column1 AND target.column2 = source.column2\nWHEN MATCHED THEN \n    DELETE; <\/code><\/pre>\n
\u9019\u6bb5\u4ee3\u78bc\u5c07\u6839\u64da\u6307\u5b9a\u7684\u689d\u4ef6\u522a\u9664\u91cd\u8907\u7684\u884c\u3002<\/p>\n
\u7e3d\u7d50<\/h2>\n
\u5728SQL Server\u4e2d\uff0c\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6cd5\u6709\u5f88\u591a\uff0c\u5305\u62ec\u4f7f\u7528CTE\u3001GROUP BY\u3001TEMP TABLE\u3001DELETE JOIN\u4ee5\u53caSQL Server\u7684\u5167\u5efa\u529f\u80fd\u7b49\u3002\u9078\u64c7\u5408\u9069\u7684\u65b9\u6cd5\u53d6\u6c7a\u65bc\u5177\u9ad4\u7684\u9700\u6c42\u548c\u6578\u64da\u7d50\u69cb\u3002\u6709\u6548\u5730\u7ba1\u7406\u91cd\u8907\u6578\u64da\u4e0d\u50c5\u80fd\u63d0\u9ad8\u6578\u64da\u5eab\u7684\u6027\u80fd\uff0c\u9084\u80fd\u78ba\u4fdd\u6578\u64da\u7684\u6e96\u78ba\u6027\u3002<\/p>\n
\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 VPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4f86\u904b\u884c\u60a8\u7684SQL Server\uff0cServer.HK\u63d0\u4f9b\u4e86\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u4e0d\u540c\u7528\u6236\u7684\u9700\u6c42\u3002\u7121\u8ad6\u662f \u9999\u6e2fVPS<\/a> \u9084\u662f\u5176\u4ed6\u670d\u52d9\uff0c\u6211\u5011\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u63a2\u7d22SQL Server\u4e2d\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u6709\u6548\u65b9\u6848\uff0c\u5305\u62ec\u4f7f\u7528CTE\u3001ROW_NUMBER()\u548cDELETE\u8a9e\u53e5\u7b49\u65b9\u6cd5\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-139043","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/139043","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=139043"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/139043\/revisions"}],"predecessor-version":[{"id":139044,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/139043\/revisions\/139044"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=139043"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=139043"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=139043"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}