{"id":96296,"date":"2024-10-20T08:14:16","date_gmt":"2024-10-20T00:14:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/96296\/"},"modified":"2024-10-20T08:14:16","modified_gmt":"2024-10-20T00:14:16","slug":"oracle%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%80%a3%e6%8e%a5%e7%9a%84%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/96296\/","title":{"rendered":"Oracle\u5b57\u7b26\u4e32\u9023\u63a5\u7684\u65b9\u6cd5"},"content":{"rendered":"<h1 id=\"oracle%e5%ad%97%e7%ac%a6%e4%b8%b2%e9%80%a3%e6%8e%a5%e7%9a%84%e6%96%b9%e6%b3%95-yuRhFSbQMR\">Oracle\u5b57\u7b26\u4e32\u9023\u63a5\u7684\u65b9\u6cd5<\/h1>\n<p>\u5728Oracle\u8cc7\u6599\u5eab\u4e2d\uff0c\u5b57\u7b26\u4e32\u9023\u63a5\u662f\u4e00\u500b\u5e38\u898b\u7684\u64cd\u4f5c\uff0c\u901a\u5e38\u7528\u65bc\u5408\u4f75\u591a\u500b\u5b57\u7b26\u4e32\u4ee5\u5f62\u6210\u4e00\u500b\u65b0\u7684\u5b57\u7b26\u4e32\u3002\u9019\u5728\u6578\u64da\u8655\u7406\u548c\u5831\u544a\u751f\u6210\u4e2d\u975e\u5e38\u6709\u7528\u3002\u672c\u6587\u5c07\u63a2\u8a0eOracle\u4e2d\u5b57\u7b26\u4e32\u9023\u63a5\u7684\u5e7e\u7a2e\u65b9\u6cd5\uff0c\u5305\u62ec\u4f7f\u7528\u904b\u7b97\u7b26\u548c\u5167\u5efa\u51fd\u6578\uff0c\u4e26\u63d0\u4f9b\u76f8\u61c9\u7684\u793a\u4f8b\u3002<\/p>\n<h2 id=\"1-%e4%bd%bf%e7%94%a8%e9%80%a3%e6%8e%a5%e9%81%8b%e7%ae%97%e7%ac%a6-yuRhFSbQMR\">1. \u4f7f\u7528\u9023\u63a5\u904b\u7b97\u7b26<\/h2>\n<p>\u5728Oracle\u4e2d\uff0c\u6700\u5e38\u7528\u7684\u5b57\u7b26\u4e32\u9023\u63a5\u904b\u7b97\u7b26\u662f\u300c||\u300d\u3002\u9019\u500b\u904b\u7b97\u7b26\u53ef\u4ee5\u5c07\u5169\u500b\u6216\u591a\u500b\u5b57\u7b26\u4e32\u9023\u63a5\u5728\u4e00\u8d77\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528\u300c||\u300d\u904b\u7b97\u7b26\u7684\u57fa\u672c\u8a9e\u6cd5\uff1a<\/p>\n<pre><code>SELECT 'Hello' || ' ' || 'World' AS greeting FROM dual;<\/code><\/pre>\n<p>\u4e0a\u8ff0\u67e5\u8a62\u5c07\u8fd4\u56de\u4e00\u500b\u540d\u70ba\u300cgreeting\u300d\u7684\u5217\uff0c\u5167\u5bb9\u70ba\u300cHello World\u300d\u3002<\/p>\n<h2 id=\"2-%e4%bd%bf%e7%94%a8concat%e5%87%bd%e6%95%b8-yuRhFSbQMR\">2. \u4f7f\u7528CONCAT\u51fd\u6578<\/h2>\n<p>\u9664\u4e86\u4f7f\u7528\u300c||\u300d\u904b\u7b97\u7b26\uff0cOracle\u9084\u63d0\u4f9b\u4e86\u5167\u5efa\u7684CONCAT\u51fd\u6578\u4f86\u9032\u884c\u5b57\u7b26\u4e32\u9023\u63a5\u3002CONCAT\u51fd\u6578\u53ea\u80fd\u63a5\u53d7\u5169\u500b\u53c3\u6578\uff0c\u56e0\u6b64\u5982\u679c\u9700\u8981\u9023\u63a5\u591a\u500b\u5b57\u7b26\u4e32\uff0c\u5247\u9700\u8981\u591a\u6b21\u4f7f\u7528\u6b64\u51fd\u6578\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528CONCAT\u51fd\u6578\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT CONCAT('Hello', ' World') AS greeting FROM dual;<\/code><\/pre>\n<p>\u5982\u679c\u9700\u8981\u9023\u63a5\u591a\u500b\u5b57\u7b26\u4e32\uff0c\u53ef\u4ee5\u9019\u6a23\u505a\uff1a<\/p>\n<pre><code>SELECT CONCAT(CONCAT('Hello', ' '), 'World') AS greeting FROM dual;<\/code><\/pre>\n<h2 id=\"3-%e4%bd%bf%e7%94%a8listagg%e5%87%bd%e6%95%b8-yuRhFSbQMR\">3. \u4f7f\u7528LISTAGG\u51fd\u6578<\/h2>\n<p>\u5728\u8655\u7406\u591a\u884c\u6578\u64da\u6642\uff0cLISTAGG\u51fd\u6578\u662f\u4e00\u500b\u975e\u5e38\u6709\u7528\u7684\u5de5\u5177\u3002\u5b83\u53ef\u4ee5\u5c07\u591a\u884c\u6578\u64da\u5408\u4f75\u70ba\u4e00\u884c\uff0c\u4e26\u4f7f\u7528\u6307\u5b9a\u7684\u5206\u9694\u7b26\u3002\u4ee5\u4e0b\u662fLISTAGG\u7684\u57fa\u672c\u7528\u6cd5\uff1a<\/p>\n<pre><code>SELECT department_id, LISTAGG(employee_name, ', ') WITHIN GROUP (ORDER BY employee_name) AS employees\nFROM employees\nGROUP BY department_id;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6bcf\u500b\u90e8\u9580\u7684\u54e1\u5de5\u540d\u7a31\uff0c\u4e26\u7528\u9017\u865f\u5206\u9694\u3002<\/p>\n<h2 id=\"4-%e4%bd%bf%e7%94%a8xmlagg%e5%87%bd%e6%95%b8-yuRhFSbQMR\">4. \u4f7f\u7528XMLAGG\u51fd\u6578<\/h2>\n<p>\u53e6\u4e00\u500b\u53ef\u4ee5\u7528\u4f86\u9023\u63a5\u5b57\u7b26\u4e32\u7684\u51fd\u6578\u662fXMLAGG\u3002\u9019\u500b\u51fd\u6578\u901a\u5e38\u7528\u65bc\u8655\u7406\u5927\u91cf\u6578\u64da\uff0c\u4e26\u4e14\u53ef\u4ee5\u63d0\u4f9b\u66f4\u597d\u7684\u6027\u80fd\u3002\u4ee5\u4e0b\u662fXMLAGG\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT department_id, XMLAGG(employee_name || ', ' ORDER BY employee_name) AS employees\nFROM employees\nGROUP BY department_id;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u7684\u6548\u679c\u8207LISTAGG\u985e\u4f3c\uff0c\u4f46\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0cXMLAGG\u53ef\u80fd\u6703\u66f4\u6709\u6548\u7387\u3002<\/p>\n<h2 id=\"5-%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-yuRhFSbQMR\">5. \u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5728\u9032\u884c\u5b57\u7b26\u4e32\u9023\u63a5\u6642\uff0c\u6709\u5e7e\u9ede\u9700\u8981\u6ce8\u610f\uff1a<\/p>\n<ul>\n<li>\u7576\u9023\u63a5\u7684\u5b57\u7b26\u4e32\u4e2d\u5305\u542bNULL\u503c\u6642\uff0c\u7d50\u679c\u5c07\u6703\u662fNULL\u3002\u70ba\u4e86\u907f\u514d\u9019\u7a2e\u60c5\u6cc1\uff0c\u53ef\u4ee5\u4f7f\u7528NVL\u51fd\u6578\u4f86\u8655\u7406NULL\u503c\u3002<\/li>\n<li>\u5728\u4f7f\u7528LISTAGG\u548cXMLAGG\u6642\uff0c\u9700\u6ce8\u610f\u8fd4\u56de\u7684\u5b57\u7b26\u4e32\u9577\u5ea6\u9650\u5236\uff0c\u8d85\u904e\u9650\u5236\u53ef\u80fd\u6703\u5c0e\u81f4\u932f\u8aa4\u3002<\/li>\n<li>\u5728\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\uff0c\u9078\u64c7\u5408\u9069\u7684\u5b57\u7b26\u4e32\u9023\u63a5\u65b9\u6cd5\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-yuRhFSbQMR\">\u7e3d\u7d50<\/h2>\n<p>\u5728Oracle\u4e2d\uff0c\u5b57\u7b26\u4e32\u9023\u63a5\u662f\u4e00\u500b\u57fa\u672c\u800c\u91cd\u8981\u7684\u64cd\u4f5c\uff0c\u7121\u8ad6\u662f\u4f7f\u7528\u300c||\u300d\u904b\u7b97\u7b26\u3001CONCAT\u51fd\u6578\u3001LISTAGG\u9084\u662fXMLAGG\u51fd\u6578\uff0c\u90fd\u80fd\u6709\u6548\u5730\u6eff\u8db3\u4e0d\u540c\u7684\u9700\u6c42\u3002\u4e86\u89e3\u9019\u4e9b\u65b9\u6cd5\u7684\u4f7f\u7528\u60c5\u5883\u548c\u6ce8\u610f\u4e8b\u9805\uff0c\u53ef\u4ee5\u5e6b\u52a9\u958b\u767c\u8005\u66f4\u9ad8\u6548\u5730\u8655\u7406\u6578\u64da\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bcVPS\u6216\u5176\u4ed6\u4f3a\u670d\u5668\u89e3\u6c7a\u65b9\u6848\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\uff1a<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u3001<a href=\"https:\/\/server.hk\">\u4e91\u4f3a\u670d\u5668<\/a>\u7b49\u670d\u52d9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3Oracle\u4e2d\u5b57\u7b26\u4e32\u9023\u63a5\u7684\u65b9\u6cd5\uff0c\u5305\u62ec\u4f7f\u7528`||`\u904b\u7b97\u7b26\u548c`CONCAT`\u51fd\u6578\uff0c\u63d0\u5347\u6578\u64da\u8655\u7406\u6548\u7387\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-96296","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/96296","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=96296"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/96296\/revisions"}],"predecessor-version":[{"id":96297,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/96296\/revisions\/96297"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=96296"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=96296"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=96296"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}