{"id":199921,"date":"2025-05-06T08:47:19","date_gmt":"2025-05-06T00:47:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/199921\/"},"modified":"2025-05-06T08:47:19","modified_gmt":"2025-05-06T00:47:19","slug":"oracle%e6%95%b0%e6%8d%ae%e5%ba%93%e6%9f%a5%e8%af%a2%e6%8a%80%e5%b7%a7%ef%bc%9a%e4%bb%85%e6%a3%80%e7%b4%a2%e9%87%8d%e5%a4%8d%e6%95%b0%e6%8d%ae%e7%9a%84%e4%b8%80%e4%be%8b","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/199921\/","title":{"rendered":"Oracle\u6570\u636e\u5e93\u67e5\u8be2\u6280\u5de7\uff1a\u4ec5\u68c0\u7d22\u91cd\u590d\u6570\u636e\u7684\u4e00\u4f8b"},"content":{"rendered":"<p><b><\/b> <\/p>\n<h1>Oracle\u6570\u636e\u5e93\u67e5\u8be2\u6280\u5de7\uff1a\u4ec5\u68c0\u7d22\u91cd\u590d\u6570\u636e\u7684\u4e00\u4f8b<\/h1>\n<p>\u4ece\u73b0\u5728\u5f00\u59cb\uff0c\u6211\u4eec\u8981\u52aa\u529b\u5b66\u4e60\u5566\uff01\u4eca\u5929\u6211\u7ed9\u5927\u5bb6\u5e26\u6765\uff0c\u611f\u5174\u8da3\u7684\u670b\u53cb\u8bf7\u7ee7\u7eed\u770b\u4e0b\u53bb\u5427\uff01\u4e0b\u6587\u4e2d\u7684\u5185\u5bb9\u6211\u4eec\u4e3b\u8981\u4f1a\u6d89\u53ca\u5230\u7b49\u7b49\u77e5\u8bc6\u70b9\uff0c\u5982\u679c\u5728\u9605\u8bfb\u672c\u6587\u8fc7\u7a0b\u4e2d\u6709\u9047\u5230\u4e0d\u6e05\u695a\u7684\u5730\u65b9\uff0c\u6b22\u8fce\u7559\u8a00\u5440\uff01\u6211\u4eec\u4e00\u8d77\u8ba8\u8bba\uff0c\u4e00\u8d77\u5b66\u4e60\uff01<\/p>\n<h2>Oracle\u6570\u636e\u5e93\u67e5\u8be2\u6280\u5de7\uff1a\u4ec5\u83b7\u53d6\u91cd\u590d\u6570\u636e\u4e2d\u7684\u4e00\u6761\uff0c\u9700\u8981\u5177\u4f53\u4ee3\u7801\u793a\u4f8b<\/h2>\n<p>\u5728\u5b9e\u9645\u7684\u6570\u636e\u5e93\u67e5\u8be2\u4e2d\uff0c\u7ecf\u5e38\u4f1a\u9047\u5230\u9700\u8981\u4ece\u91cd\u590d\u6570\u636e\u4e2d\u83b7\u53d6\u552f\u4e00\u4e00\u6761\u6570\u636e\u7684\u60c5\u51b5\u3002\u672c\u6587\u5c06\u4ecb\u7ecd\u5982\u4f55\u5229\u7528Oracle\u6570\u636e\u5e93\u7684\u6280\u5de7\uff0c\u5b9e\u73b0\u4ec5\u83b7\u53d6\u91cd\u590d\u6570\u636e\u4e2d\u7684\u4e00\u6761\u8bb0\u5f55\u7684\u65b9\u6cd5\uff0c\u5e76\u63d0\u4f9b\u5177\u4f53\u7684\u4ee3\u7801\u793a\u4f8b\u3002<\/p>\n<h3>\u573a\u666f\u63cf\u8ff0<\/h3>\n<p>\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u5f20\u540d\u4e3a<code>employee<\/code>\u7684\u8868\uff0c\u5176\u4e2d\u5305\u542b\u4e86\u5458\u5de5\u7684\u4fe1\u606f\uff0c\u53ef\u80fd\u5b58\u5728\u91cd\u590d\u7684\u5458\u5de5\u4fe1\u606f\u3002\u6211\u4eec\u9700\u8981\u67e5\u8be2\u51fa\u6240\u6709\u91cd\u590d\u5458\u5de5\u4fe1\u606f\u4e2d\u7684\u4efb\u610f\u4e00\u6761\u8bb0\u5f55\uff0c\u800c\u4e0d\u662f\u83b7\u53d6\u6240\u6709\u91cd\u590d\u7684\u5458\u5de5\u4fe1\u606f\u3002<\/p>\n<h3>\u67e5\u8be2\u5b9e\u73b0<\/h3>\n<p>\u6211\u4eec\u53ef\u4ee5\u5229\u7528Oracle\u6570\u636e\u5e93\u4e2d\u7684\u7a97\u53e3\u51fd\u6570<code>ROW_NUMBER()<\/code>\u7ed3\u5408<code>PARTITION BY<\/code>\u8bed\u53e5\u6765\u5b9e\u73b0\u8fd9\u4e00\u9700\u6c42\u3002\u5177\u4f53\u5b9e\u73b0\u7684\u601d\u8def\u662f\u4e3a\u6bcf\u6761\u8bb0\u5f55\u7f16\u6392\u4e00\u4e2a\u5e8f\u53f7\uff0c\u7136\u540e\u7b5b\u9009\u51fa\u5e8f\u53f7\u4e3a1\u7684\u8bb0\u5f55\uff0c\u5373\u53ef\u83b7\u53d6\u6bcf\u7ec4\u91cd\u590d\u6570\u636e\u4e2d\u7684\u7b2c\u4e00\u6761\u8bb0\u5f55\u3002<\/p>\n<p>\u4ee5\u4e0b\u662f\u57fa\u4e8e\u4e0a\u8ff0\u601d\u8def\u5b9e\u73b0\u7684\u5177\u4f53\u4ee3\u7801\u793a\u4f8b\uff1a<\/p>\n<pre>SELECT *\nFROM (\n    SELECT \n        e.*,\n        ROW_NUMBER() OVER (PARTITION BY e.employee_id ORDER BY e.employee_id) AS rn\n    FROM employee e\n) tmp\nWHERE rn = 1;<\/pre>\n<p>\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c\u9996\u5148\u901a\u8fc7\u5b50\u67e5\u8be2\u4e3a\u6bcf\u6761\u8bb0\u5f55\u6dfb\u52a0\u4e86\u4e00\u4e2a\u5e8f\u53f7<code>rn<\/code>\uff0c\u5e76\u6839\u636e<code>employee_id<\/code>\u5b57\u6bb5\u8fdb\u884c\u5206\u7ec4\u3002\u7136\u540e\u5728\u5916\u90e8\u67e5\u8be2\u4e2d\u7b5b\u9009\u51fa\u5e8f\u53f7\u4e3a1\u7684\u8bb0\u5f55\uff0c\u5373\u53ef\u5f97\u5230\u6bcf\u7ec4\u91cd\u590d\u6570\u636e\u4e2d\u7684\u7b2c\u4e00\u6761\u8bb0\u5f55\u3002<\/p>\n<h3>\u793a\u4f8b\u8bf4\u660e<\/h3>\n<p>\u5047\u8bbe<code>employee<\/code>\u8868\u7684\u7ed3\u6784\u5982\u4e0b\uff1a<\/p>\n<table>\n<thead>\n<tr>\n<th>employee_id<\/th>\n<th>name<\/th>\n<th>department<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1<\/td>\n<td>\u5f20\u4e09<\/td>\n<td>\u6280\u672f\u90e8<\/td>\n<\/tr>\n<tr>\n<td>2<\/td>\n<td>\u674e\u56db<\/td>\n<td>\u9500\u552e\u90e8<\/td>\n<\/tr>\n<tr>\n<td>3<\/td>\n<td>\u738b\u4e94<\/td>\n<td>\u8d22\u52a1\u90e8<\/td>\n<\/tr>\n<tr>\n<td>1<\/td>\n<td>\u5f20\u4e09<\/td>\n<td>\u6280\u672f\u90e8<\/td>\n<\/tr>\n<tr>\n<td>2<\/td>\n<td>\u674e\u56db<\/td>\n<td>\u9500\u552e\u90e8<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u6267\u884c\u4e0a\u8ff0\u4ee3\u7801\u793a\u4f8b\u540e\uff0c\u5c06\u4f1a\u8fd4\u56de\u4ee5\u4e0b\u7ed3\u679c\uff1a<\/p>\n<table>\n<thead>\n<tr>\n<th>employee_id<\/th>\n<th>name<\/th>\n<th>department<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1<\/td>\n<td>\u5f20\u4e09<\/td>\n<td>\u6280\u672f\u90e8<\/td>\n<\/tr>\n<tr>\n<td>2<\/td>\n<td>\u674e\u56db<\/td>\n<td>\u9500\u552e\u90e8<\/td>\n<\/tr>\n<tr>\n<td>3<\/td>\n<td>\u738b\u4e94<\/td>\n<td>\u8d22\u52a1\u90e8<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u901a\u8fc7\u4ee5\u4e0a\u793a\u4f8b\u53ef\u4ee5\u770b\u51fa\uff0c\u6211\u4eec\u6210\u529f\u5730\u4ece\u91cd\u590d\u6570\u636e\u4e2d\u83b7\u53d6\u4e86\u6bcf\u7ec4\u6570\u636e\u4e2d\u7684\u7b2c\u4e00\u6761\u8bb0\u5f55\uff0c\u5b9e\u73b0\u4e86\u6211\u4eec\u7684\u67e5\u8be2\u9700\u6c42\u3002<\/p>\n<h3>\u603b\u7ed3<\/h3>\n<p>\u672c\u6587\u4ecb\u7ecd\u4e86\u5728Oracle\u6570\u636e\u5e93\u4e2d\u4ec5\u83b7\u53d6\u91cd\u590d\u6570\u636e\u4e2d\u7684\u4e00\u6761\u8bb0\u5f55\u7684\u5b9e\u73b0\u65b9\u6cd5\uff0c\u5e76\u63d0\u4f9b\u4e86\u5177\u4f53\u7684\u4ee3\u7801\u793a\u4f8b\u3002\u901a\u8fc7\u5229\u7528\u7a97\u53e3\u51fd\u6570<code>ROW_NUMBER()<\/code>\u548c<code>PARTITION BY<\/code>\u8bed\u53e5\uff0c\u6211\u4eec\u53ef\u4ee5\u8f7b\u677e\u5730\u5b9e\u73b0\u8fd9\u4e00\u9700\u6c42\uff0c\u63d0\u5347\u4e86\u67e5\u8be2\u6548\u7387\u548c\u6570\u636e\u5904\u7406\u7684\u51c6\u786e\u6027\u3002\u5e0c\u671b\u672c\u6587\u5bf9\u60a8\u5728\u5b9e\u9645\u7684\u6570\u636e\u5e93\u67e5\u8be2\u5de5\u4f5c\u4e2d\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n<p>\u7406\u8bba\u8981\u638c\u63e1\uff0c\u5b9e\u64cd\u4e0d\u80fd\u843d\uff01\u4ee5\u4e0a\u5173\u4e8e\u300aOracle\u6570\u636e\u5e93\u67e5\u8be2\u6280\u5de7\uff1a\u4ec5\u68c0\u7d22\u91cd\u590d\u6570\u636e\u7684\u4e00\u4f8b\u300b\u7684\u8be6\u7ec6\u4ecb\u7ecd\uff0c\u5927\u5bb6\u90fd\u638c\u63e1\u4e86\u5427\uff01\u5982\u679c\u60f3\u8981\u7ee7\u7eed\u63d0\u5347\u81ea\u5df1\u7684\u80fd\u529b\uff0c\u90a3\u4e48\u5c31\u6765\u5173\u6ce8\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\u5427\uff01<\/p>\n<dl>\n<dt>\n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"<p>Oracle\u6570\u636e\u5e93\u67e5\u8be2\u6280\u5de7\uff1a\u4ec5\u68c0&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-199921","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199921","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"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=199921"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199921\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=199921"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=199921"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=199921"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}