{"id":94946,"date":"2024-10-19T20:57:16","date_gmt":"2024-10-19T12:57:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/94946\/"},"modified":"2024-10-19T20:57:17","modified_gmt":"2024-10-19T12:57:17","slug":"oracle%e6%9f%a5%e8%a9%a2%e9%87%8d%e8%a4%87%e8%a8%98%e9%8c%84%e7%9a%84%e4%b8%89%e7%a8%ae%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/94946\/","title":{"rendered":"Oracle\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u4e09\u7a2e\u65b9\u6cd5"},"content":{"rendered":"

Oracle\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u4e09\u7a2e\u65b9\u6cd5<\/h1>\n

\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u8a18\u9304\u7684\u5b58\u5728\u53ef\u80fd\u6703\u5c0e\u81f4\u6578\u64da\u4e0d\u4e00\u81f4\u6027\u548c\u67e5\u8a62\u6548\u7387\u7684\u964d\u4f4e\u3002Oracle\u6578\u64da\u5eab\u63d0\u4f9b\u4e86\u591a\u7a2e\u65b9\u6cd5\u4f86\u67e5\u8a62\u548c\u8b58\u5225\u91cd\u8907\u8a18\u9304\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u4e09\u7a2e\u5e38\u7528\u7684\u65b9\u6cd5\uff0c\u5e6b\u52a9\u7528\u6236\u6709\u6548\u5730\u67e5\u627e\u548c\u8655\u7406\u91cd\u8907\u6578\u64da\u3002<\/p>\n

\u65b9\u6cd5\u4e00\uff1a\u4f7f\u7528GROUP BY\u548cHAVING\u5b50\u53e5<\/h2>\n

\u6700\u5e38\u898b\u7684\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u65b9\u6cd5\u662f\u4f7f\u7528SQL\u7684GROUP BY\u548cHAVING\u5b50\u53e5\u3002\u9019\u7a2e\u65b9\u6cd5\u53ef\u4ee5\u6839\u64da\u7279\u5b9a\u7684\u5217\u9032\u884c\u5206\u7d44\uff0c\u7136\u5f8c\u4f7f\u7528HAVING\u5b50\u53e5\u4f86\u7be9\u9078\u51fa\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n

\nSELECT column_name, COUNT(*)\nFROM table_name\nGROUP BY column_name\nHAVING COUNT(*) > 1;\n<\/code><\/pre>\n
\u5728\u9019\u6bb5\u4ee3\u78bc\u4e2d\uff0ccolumn_name<\/code>\u662f\u9700\u8981\u6aa2\u67e5\u91cd\u8907\u7684\u5217\u540d\uff0ctable_name<\/code>\u662f\u6578\u64da\u8868\u7684\u540d\u7a31\u3002\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u91cd\u8907\u7684column_name<\/code>\u503c\u53ca\u5176\u51fa\u73fe\u7684\u6b21\u6578\u3002<\/p>\n
\u65b9\u6cd5\u4e8c\uff1a\u4f7f\u7528ROW_NUMBER()\u51fd\u6578<\/h2>\n
\u53e6\u4e00\u7a2e\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u65b9\u6cd5\u662f\u4f7f\u7528ROW_NUMBER()<\/code>\u7a97\u53e3\u51fd\u6578\u3002\u9019\u7a2e\u65b9\u6cd5\u53ef\u4ee5\u70ba\u6bcf\u4e00\u884c\u5206\u914d\u4e00\u500b\u552f\u4e00\u7684\u5e8f\u865f\uff0c\u7136\u5f8c\u6839\u64da\u9019\u500b\u5e8f\u865f\u4f86\u8b58\u5225\u91cd\u8907\u7684\u8a18\u9304\u3002<\/p>\n
\nWITH RankedRecords AS (\n    SELECT column_name, \n           ROW_NUMBER() OVER (PARTITION BY column_name ORDER BY column_name) AS row_num\n    FROM table_name\n)\nSELECT column_name\nFROM RankedRecords\nWHERE row_num > 1;\n<\/code><\/pre>\n
\u5728\u9019\u6bb5\u4ee3\u78bc\u4e2d\uff0cPARTITION BY<\/code>\u5b50\u53e5\u7528\u65bc\u6839\u64dacolumn_name<\/code>\u9032\u884c\u5206\u7d44\uff0c\u800cORDER BY<\/code>\u5247\u78ba\u5b9a\u4e86\u6bcf\u7d44\u5167\u7684\u6392\u5e8f\u3002\u6700\u7d42\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u91cd\u8907\u7684column_name<\/code>\u503c\u3002<\/p>\n
\u65b9\u6cd5\u4e09\uff1a\u4f7f\u7528JOIN\u64cd\u4f5c<\/h2>\n
\u6700\u5f8c\u4e00\u7a2e\u65b9\u6cd5\u662f\u4f7f\u7528JOIN\u64cd\u4f5c\u4f86\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u3002\u9019\u7a2e\u65b9\u6cd5\u901a\u904e\u5c07\u8868\u81ea\u8eab\u9032\u884c\u9023\u63a5\u4f86\u67e5\u627e\u91cd\u8907\u7684\u884c\u3002<\/p>\n
\nSELECT a.column_name\nFROM table_name a\nJOIN table_name b ON a.column_name = b.column_name\nWHERE a.rowid  b.rowid;\n<\/code><\/pre>\n
\u5728\u9019\u6bb5\u4ee3\u78bc\u4e2d\uff0ca<\/code>\u548cb<\/code>\u662f\u540c\u4e00\u500b\u8868\u7684\u5169\u500b\u5225\u540d\u3002\u901a\u904e\u6bd4\u8f03rowid<\/code>\uff0c\u53ef\u4ee5\u627e\u5230\u6240\u6709\u91cd\u8907\u7684\u8a18\u9304\u3002\u9019\u7a2e\u65b9\u6cd5\u7279\u5225\u9069\u5408\u65bc\u9700\u8981\u67e5\u8a62\u591a\u500b\u5217\u7684\u60c5\u6cc1\u3002<\/p>\n
\u7e3d\u7d50<\/h2>\n
\u5728Oracle\u6578\u64da\u5eab\u4e2d\uff0c\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u4e09\u7a2e\u65b9\u6cd5\u5404\u6709\u5176\u512a\u7f3a\u9ede\u3002\u4f7f\u7528GROUP BY<\/code>\u548cHAVING<\/code>\u5b50\u53e5\u7684\u65b9\u6cd5\u7c21\u55ae\u76f4\u89c0\uff0c\u9069\u5408\u65bc\u5c0f\u578b\u6578\u64da\u96c6\uff1b\u800cROW_NUMBER()<\/code>\u51fd\u6578\u5247\u63d0\u4f9b\u4e86\u66f4\u9748\u6d3b\u7684\u67e5\u8a62\u65b9\u5f0f\uff0c\u9069\u5408\u65bc\u9700\u8981\u9032\u884c\u66f4\u8907\u96dc\u64cd\u4f5c\u7684\u60c5\u6cc1\uff1b\u6700\u5f8c\uff0c\u4f7f\u7528JOIN\u64cd\u4f5c\u7684\u65b9\u6cd5\u5247\u80fd\u5920\u6709\u6548\u5730\u67e5\u8a62\u591a\u5217\u91cd\u8907\u8a18\u9304\u3002\u6839\u64da\u5177\u9ad4\u9700\u6c42\u9078\u64c7\u5408\u9069\u7684\u65b9\u6cd5\uff0c\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u8655\u7406\u7684\u6548\u7387\u548c\u6e96\u78ba\u6027\u3002<\/p>\n
\u5982\u679c\u60a8\u9700\u8981\u9ad8\u6548\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528\u6211\u5011\u7684\u9999\u6e2fVPS<\/a>\u670d\u52d9\uff0c\u70ba\u60a8\u7684\u696d\u52d9\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u63a2\u7d22Oracle\u4e2d\u67e5\u8a62\u91cd\u8907\u8a18\u9304\u7684\u4e09\u7a2e\u65b9\u6cd5\uff0c\u63d0\u5347\u6578\u64da\u7ba1\u7406\u6548\u7387\uff0c\u78ba\u4fdd\u6578\u64da\u6e96\u78ba\u6027\u8207\u5b8c\u6574\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-94946","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94946","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=94946"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94946\/revisions"}],"predecessor-version":[{"id":94947,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94946\/revisions\/94947"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=94946"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=94946"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=94946"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}