{"id":188840,"date":"2024-11-12T02:19:24","date_gmt":"2024-11-11T18:19:24","guid":{"rendered":"https:\/\/server.hk\/cnblog\/188840\/"},"modified":"2024-11-12T02:19:25","modified_gmt":"2024-11-11T18:19:25","slug":"%e6%8e%a2%e8%a8%8eoracle%e4%b8%adrownum%e7%9a%84%e7%94%a8%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/188840\/","title":{"rendered":"\u63a2\u8a0eOracle\u4e2dRownum\u7684\u7528\u6cd5"},"content":{"rendered":"<h1 id=\"%e6%8e%a2%e8%a8%8eoracle%e4%b8%adrownum%e7%9a%84%e7%94%a8%e6%b3%95-TgjGXBUnif\">\u63a2\u8a0eOracle\u4e2dRownum\u7684\u7528\u6cd5<\/h1>\n<p>\u5728Oracle\u8cc7\u6599\u5eab\u4e2d\uff0c<code>Rownum<\/code>\u662f\u4e00\u500b\u975e\u5e38\u91cd\u8981\u7684\u6982\u5ff5\uff0c\u4e3b\u8981\u7528\u65bc\u9650\u5236\u67e5\u8a62\u7d50\u679c\u7684\u884c\u6578\u3002\u5b83\u662f\u4e00\u500b\u865b\u64ec\u7684\u5217\uff0c\u8868\u793a\u67e5\u8a62\u7d50\u679c\u96c6\u4e2d\u6bcf\u4e00\u884c\u7684\u5e8f\u865f\u3002\u9019\u7bc7\u6587\u7ae0\u5c07\u6df1\u5165\u63a2\u8a0e<code>Rownum<\/code>\u7684\u7528\u6cd5\u53ca\u5176\u5728\u5be6\u969b\u61c9\u7528\u4e2d\u7684\u4e00\u4e9b\u6ce8\u610f\u4e8b\u9805\u3002<\/p>\n<h2 id=\"rownum%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-TgjGXBUnif\">Rownum\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>\u5728Oracle\u4e2d\uff0c<code>Rownum<\/code>\u662f\u5f9e1\u958b\u59cb\u7684\u6574\u6578\uff0c\u5c0d\u65bc\u67e5\u8a62\u7d50\u679c\u4e2d\u7684\u6bcf\u4e00\u884c\uff0cOracle\u6703\u81ea\u52d5\u5206\u914d\u4e00\u500b\u5e8f\u865f\u3002\u9019\u610f\u5473\u8457\u5728\u67e5\u8a62\u57f7\u884c\u6642\uff0c<code>Rownum<\/code>\u7684\u503c\u662f\u6839\u64da\u884c\u7684\u8fd4\u56de\u9806\u5e8f\u800c\u5b9a\u7684\u3002\u9019\u4e00\u7279\u6027\u4f7f\u5f97<code>Rownum<\/code>\u5728\u9650\u5236\u67e5\u8a62\u7d50\u679c\u884c\u6578\u6642\u975e\u5e38\u6709\u7528\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8rownum%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-TgjGXBUnif\">\u4f7f\u7528Rownum\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>\u4f7f\u7528<code>Rownum<\/code>\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT * FROM \u8868\u540d WHERE ROWNUM &lt;= \u6578\u91cf;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5982\u679c\u6211\u5011\u60f3\u5f9e\u4e00\u500b\u540d\u70ba<code>employees<\/code>\u7684\u8868\u4e2d\u9078\u64c7\u524d10\u540d\u54e1\u5de5\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT * FROM employees WHERE ROWNUM &lt;= 10;<\/code><\/pre>\n<h2 id=\"rownum%e7%9a%84%e7%89%b9%e6%80%a7%e8%88%87%e9%99%90%e5%88%b6-TgjGXBUnif\">Rownum\u7684\u7279\u6027\u8207\u9650\u5236<\/h2>\n<p>\u96d6\u7136<code>Rownum<\/code>\u5728\u67e5\u8a62\u4e2d\u975e\u5e38\u6709\u7528\uff0c\u4f46\u5b83\u4e5f\u6709\u4e00\u4e9b\u7279\u6027\u548c\u9650\u5236\u9700\u8981\u6ce8\u610f\uff1a<\/p>\n<ul>\n<li><strong>\u884c\u865f\u7684\u5206\u914d\u9806\u5e8f\uff1a<\/strong>\u5728\u67e5\u8a62\u57f7\u884c\u6642\uff0c<code>Rownum<\/code>\u662f\u6839\u64da\u884c\u7684\u8fd4\u56de\u9806\u5e8f\u5206\u914d\u7684\u3002\u56e0\u6b64\uff0c\u5982\u679c\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528\u4e86<code>ORDER BY<\/code>\u5b50\u53e5\uff0c<code>Rownum<\/code>\u7684\u503c\u53ef\u80fd\u4e0d\u6703\u53cd\u6620\u6700\u7d42\u7684\u6392\u5e8f\u7d50\u679c\u3002<\/li>\n<li><strong>\u904e\u6ffe\u689d\u4ef6\u7684\u61c9\u7528\uff1a<\/strong>\u5728\u4f7f\u7528<code>Rownum<\/code>\u6642\uff0c\u904e\u6ffe\u689d\u4ef6\u61c9\u8a72\u653e\u5728<code>WHERE<\/code>\u5b50\u53e5\u4e2d\uff0c\u800c\u4e0d\u662f\u5728<code>HAVING<\/code>\u5b50\u53e5\u4e2d\uff0c\u56e0\u70ba<code>Rownum<\/code>\u662f\u5728<code>WHERE<\/code>\u5b50\u53e5\u4e2d\u8a08\u7b97\u7684\u3002<\/li>\n<li><strong>\u8207\u5b50\u67e5\u8a62\u7684\u7d50\u5408\uff1a<\/strong>\u5982\u679c\u9700\u8981\u5728\u6392\u5e8f\u5f8c\u9650\u5236\u884c\u6578\uff0c\u53ef\u4ee5\u4f7f\u7528\u5b50\u67e5\u8a62\u3002\u4f8b\u5982\uff1a<\/strong><\/li>\n<\/ul>\n<pre><code>SELECT * FROM (SELECT * FROM employees ORDER BY salary DESC) WHERE ROWNUM &lt;= 10;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u6703\u9996\u5148\u6839\u64da\u85aa\u6c34\u964d\u5e8f\u6392\u5217\u6240\u6709\u54e1\u5de5\uff0c\u7136\u5f8c\u518d\u9078\u64c7\u524d10\u540d\u3002<\/p>\n<h2 id=\"rownum%e8%88%87%e5%85%b6%e4%bb%96%e5%8a%9f%e8%83%bd%e7%9a%84%e7%b5%90%e5%90%88-TgjGXBUnif\">Rownum\u8207\u5176\u4ed6\u529f\u80fd\u7684\u7d50\u5408<\/h2>\n<p>\u9664\u4e86\u57fa\u672c\u7684\u884c\u6578\u9650\u5236\uff0c<code>Rownum<\/code>\u9084\u53ef\u4ee5\u8207\u5176\u4ed6Oracle\u529f\u80fd\u7d50\u5408\u4f7f\u7528\uff0c\u4f8b\u5982<code>ROW_NUMBER()<\/code>\u51fd\u6578\u3002<code>ROW_NUMBER()<\/code>\u51fd\u6578\u53ef\u4ee5\u5728\u67e5\u8a62\u4e2d\u63d0\u4f9b\u66f4\u9748\u6d3b\u7684\u884c\u865f\u5206\u914d\uff0c\u4e26\u4e14\u53ef\u4ee5\u5728<code>OVER()<\/code>\u5b50\u53e5\u4e2d\u6307\u5b9a\u6392\u5e8f\u898f\u5247\u3002<\/p>\n<pre><code>SELECT employee_id, salary, ROW_NUMBER() OVER (ORDER BY salary DESC) AS row_num FROM employees;<\/code><\/pre>\n<p>\u9019\u6a23\u7684\u67e5\u8a62\u6703\u70ba\u6bcf\u4f4d\u54e1\u5de5\u6839\u64da\u85aa\u6c34\u5206\u914d\u4e00\u500b\u884c\u865f\uff0c\u4e26\u4e14\u53ef\u4ee5\u9032\u4e00\u6b65\u904e\u6ffe\u6216\u6392\u5e8f\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-TgjGXBUnif\">\u7e3d\u7d50<\/h2>\n<p>\u5728Oracle\u8cc7\u6599\u5eab\u4e2d\uff0c<code>Rownum<\/code>\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u7528\u65bc\u9650\u5236\u67e5\u8a62\u7d50\u679c\u7684\u884c\u6578\u3002\u96d6\u7136\u5b83\u6709\u4e00\u4e9b\u7279\u6027\u548c\u9650\u5236\uff0c\u4f46\u901a\u904e\u5408\u7406\u7684\u4f7f\u7528\uff0c\u53ef\u4ee5\u6709\u6548\u5730\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\u3002\u5728\u5be6\u969b\u61c9\u7528\u4e2d\uff0c\u7d50\u5408<code>ROW_NUMBER()<\/code>\u7b49\u5176\u4ed6\u529f\u80fd\uff0c\u53ef\u4ee5\u5be6\u73fe\u66f4\u8907\u96dc\u7684\u67e5\u8a62\u9700\u6c42\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc<code>Rownum<\/code>\u7684\u4f7f\u7528\u6709\u9032\u4e00\u6b65\u7684\u9700\u6c42\uff0c\u6216\u662f\u9700\u8981\u9ad8\u6548\u7684<code><a href=\"https:\/\/server.hk\">VPS<\/a><\/code> \u89e3\u6c7a\u65b9\u6848\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6df1\u5165\u63a2\u8a0eOracle\u4e2dRownum\u7684\u7528\u6cd5\uff0c\u4e86\u89e3\u5982\u4f55\u6709\u6548\u9650\u5236\u67e5\u8a62\u7d50\u679c\u53ca\u5176\u5728\u6578\u64da\u5eab\u64cd\u4f5c\u4e2d\u7684\u61c9\u7528\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-188840","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/188840","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=188840"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/188840\/revisions"}],"predecessor-version":[{"id":188841,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/188840\/revisions\/188841"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=188840"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=188840"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=188840"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}