{"id":199944,"date":"2025-05-06T10:08:19","date_gmt":"2025-05-06T02:08:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/199944\/"},"modified":"2025-05-06T10:08:19","modified_gmt":"2025-05-06T02:08:19","slug":"%e7%ae%80%e5%8c%96%e6%95%b0%e6%8d%ae%e5%a4%84%e7%90%86%e6%93%8d%e4%bd%9c%ef%bc%9aoracle-decode%e5%87%bd%e6%95%b0%e7%9a%84%e5%ae%9e%e7%94%a8%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/199944\/","title":{"rendered":"\u7b80\u5316\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff1aOracle DECODE\u51fd\u6570\u7684\u5b9e\u7528\u65b9\u6cd5"},"content":{"rendered":"<p><b><\/b> <\/p>\n<h1>\u7b80\u5316\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff1aOracle DECODE\u51fd\u6570\u7684\u5b9e\u7528\u65b9\u6cd5<\/h1>\n<\/p>\n<p>\u5728Oracle\u6570\u636e\u5e93\u4e2d\uff0c\u6709\u4e00\u79cd\u975e\u5e38\u5b9e\u7528\u7684\u51fd\u6570\u53eb\u505aDECODE\u51fd\u6570\uff0c\u5b83\u53ef\u4ee5\u5e2e\u52a9\u7b80\u5316\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff0c\u8ba9SQL\u67e5\u8be2\u53d8\u5f97\u66f4\u52a0\u9ad8\u6548\u3002DECODE\u51fd\u6570\u901a\u5e38\u7528\u4e8e\u6839\u636e\u4e0d\u540c\u6761\u4ef6\u8fd4\u56de\u4e0d\u540c\u7ed3\u679c\uff0c\u7c7b\u4f3c\u4e8e\u5176\u4ed6\u7f16\u7a0b\u8bed\u8a00\u4e2d\u7684\u6761\u4ef6\u5224\u65ad\u8bed\u53e5\u3002\u5728\u672c\u6587\u4e2d\uff0c\u6211\u4eec\u5c06\u7ed3\u5408\u5177\u4f53\u7684\u4ee3\u7801\u793a\u4f8b\u6765\u4ecb\u7ecd\u5982\u4f55\u4f7f\u7528DECODE\u51fd\u6570\uff0c\u5e76\u5c55\u793a\u5176\u5f3a\u5927\u7684\u6570\u636e\u5904\u7406\u80fd\u529b\u3002<\/p>\n<p>\u9996\u5148\uff0c\u8ba9\u6211\u4eec\u6765\u4e86\u89e3\u4e00\u4e0bDECODE\u51fd\u6570\u7684\u8bed\u6cd5\u683c\u5f0f\uff1a<\/p>\n<pre>DECODE(expr, search1, result1, search2, result2, \u2026, default)<\/pre>\n<p>\u4e0a\u9762\u7684\u8bed\u6cd5\u4e2d\uff0cexpr\u662f\u8981\u8fdb\u884c\u6bd4\u8f83\u7684\u8868\u8fbe\u5f0f\uff0csearch1\u3001search2\u7b49\u662f\u9700\u8981\u6bd4\u8f83\u7684\u503c\uff0cresult1\u3001result2\u7b49\u662f\u5bf9\u5e94\u7684\u8fd4\u56de\u503c\uff0cdefault\u662f\u5728expr\u4e0d\u5339\u914d\u4efb\u4f55search\u503c\u65f6\u7684\u9ed8\u8ba4\u8fd4\u56de\u503c\u3002<\/p>\n<p>\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u901a\u8fc7\u4e00\u4e2a\u5177\u4f53\u7684\u6848\u4f8b\u6765\u6f14\u793aDECODE\u51fd\u6570\u7684\u4f7f\u7528\u3002\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u5458\u5de5\u8868 EMPLOYEES\uff0c\u5176\u4e2d\u5305\u542b\u5458\u5de5\u7684\u59d3\u540d\u548c\u804c\u52a1\u4fe1\u606f\u3002\u73b0\u5728\uff0c\u6211\u4eec\u60f3\u521b\u5efa\u4e00\u4e2a\u67e5\u8be2\uff0c\u6839\u636e\u5458\u5de5\u7684\u804c\u52a1\u4fe1\u606f\u5c06\u5458\u5de5\u7c7b\u578b\u5206\u4e3a\u201c\u7ecf\u7406\u201d\u3001\u201c\u52a9\u7406\u201d\u548c\u201c\u666e\u901a\u5458\u5de5\u201d\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528DECODE\u51fd\u6570\u6765\u5b9e\u73b0\u8fd9\u4e2a\u529f\u80fd\u3002<\/p>\n<pre>SELECT\n    employee_name,\n    job_title,\n    DECODE(job_title, 'Manager', '\u7ecf\u7406', 'Assistant', '\u52a9\u7406', 'Employee', '\u666e\u901a\u5458\u5de5', '\u5176\u4ed6') AS employee_type\nFROM\n    EMPLOYEES;<\/pre>\n<p>\u5728\u4e0a\u9762\u7684\u67e5\u8be2\u8bed\u53e5\u4e2d\uff0c\u6211\u4eec\u4f7f\u7528\u4e86DECODE\u51fd\u6570\u6765\u6839\u636e\u4e0d\u540c\u7684\u804c\u52a1\u4fe1\u606f\u5c06\u5458\u5de5\u7c7b\u578b\u8fdb\u884c\u5206\u7c7b\uff0c\u5e76\u8fd4\u56de\u4e0d\u540c\u7684\u5458\u5de5\u7c7b\u578b\u540d\u79f0\u3002\u5982\u679cjob_title\u4e3a&#8217;Manager&#8217;\uff0c\u5219\u8fd4\u56de&#8217;\u7ecf\u7406&#8217;\uff1b\u5982\u679c\u4e3a&#8217;Assistant&#8217;\uff0c\u5219\u8fd4\u56de&#8217;\u52a9\u7406&#8217;\uff1b\u5982\u679c\u4e3a&#8217;Employee&#8217;\uff0c\u5219\u8fd4\u56de&#8217;\u666e\u901a\u5458\u5de5&#8217;\uff1b\u5982\u679c\u4e0d\u5339\u914d\u4efb\u4f55\u6761\u4ef6\uff0c\u5219\u8fd4\u56de&#8217;\u5176\u4ed6&#8217;\u3002<\/p>\n<p>\u901a\u8fc7\u8fd9\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230DECODE\u51fd\u6570\u7684\u5f3a\u5927\u4e4b\u5904\uff0c\u5b83\u53ef\u4ee5\u5e2e\u52a9\u6211\u4eec\u7b80\u5316\u590d\u6742\u7684\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff0c\u8ba9SQL\u67e5\u8be2\u53d8\u5f97\u66f4\u52a0\u76f4\u89c2\u548c\u9ad8\u6548\u3002<\/p>\n<p>\u9664\u4e86\u4e0a\u9762\u7684\u793a\u4f8b\uff0cDECODE\u51fd\u6570\u8fd8\u53ef\u4ee5\u5e94\u7528\u4e8e\u66f4\u590d\u6742\u7684\u6570\u636e\u5904\u7406\u573a\u666f\uff0c\u6bd4\u5982\u5bf9\u65e5\u671f\u3001\u6570\u5b57\u7b49\u6570\u636e\u7c7b\u578b\u8fdb\u884c\u6761\u4ef6\u5224\u65ad\u548c\u5904\u7406\u3002\u901a\u8fc7\u7075\u6d3b\u8fd0\u7528DECODE\u51fd\u6570\uff0c\u6211\u4eec\u53ef\u4ee5\u5728Oracle\u6570\u636e\u5e93\u4e2d\u8fdb\u884c\u66f4\u52a0\u591a\u6837\u5316\u548c\u9ad8\u6548\u7684\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff0c\u63d0\u5347\u6570\u636e\u5904\u7406\u7684\u6548\u7387\u548c\u53ef\u8bfb\u6027\u3002<\/p>\n<p>\u603b\u7ed3\u8d77\u6765\uff0cDECODE\u51fd\u6570\u662fOracle\u6570\u636e\u5e93\u4e2d\u4e00\u79cd\u975e\u5e38\u5b9e\u7528\u7684\u51fd\u6570\uff0c\u5b83\u53ef\u4ee5\u5e2e\u52a9\u7b80\u5316\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff0c\u63d0\u5347SQL\u67e5\u8be2\u7684\u6548\u7387\u548c\u53ef\u8bfb\u6027\u3002\u901a\u8fc7\u5b66\u4e60\u548c\u638c\u63e1DECODE\u51fd\u6570\u7684\u7528\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u66f4\u597d\u5730\u5904\u7406\u548c\u5206\u6790\u6570\u636e\uff0c\u4e3a\u4e1a\u52a1\u51b3\u7b56\u63d0\u4f9b\u66f4\u6709\u529b\u7684\u652f\u6301\u3002\u5e0c\u671b\u672c\u6587\u80fd\u5bf9\u5927\u5bb6\u4e86\u89e3\u548c\u5e94\u7528DECODE\u51fd\u6570\u6709\u6240\u5e2e\u52a9\uff0c\u8ba9\u6570\u636e\u5904\u7406\u53d8\u5f97\u66f4\u52a0\u8f7b\u677e\u548c\u9ad8\u6548\u3002<\/p>\n<p>\u5230\u8fd9\u91cc\uff0c\u6211\u4eec\u4e5f\u5c31\u8bb2\u5b8c\u4e86\u300a\u7b80\u5316\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff1aOracle DECODE\u51fd\u6570\u7684\u5b9e\u7528\u65b9\u6cd5\u300b\u7684\u5185\u5bb9\u4e86\u3002\u4e2a\u4eba\u8ba4\u4e3a\uff0c\u57fa\u7840\u77e5\u8bc6\u7684\u5b66\u4e60\u548c\u5de9\u56fa\uff0c\u662f\u4e3a\u4e86\u66f4\u597d\u7684\u5c06\u5176\u8fd0\u7528\u5230\u9879\u76ee\u4e2d\uff0c\u6b22\u8fce\u5173\u6ce8\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\uff0c\u5e26\u4f60\u4e86\u89e3\u66f4\u591a\u5173\u4e8eOracle,\u6570\u636e\u5904\u7406,DECODE\u7684\u77e5\u8bc6\u70b9\uff01<\/p>\n<dl>\n<dt>\n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"<p>\u7b80\u5316\u6570\u636e\u5904\u7406\u64cd\u4f5c\uff1aOracle &#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-199944","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199944","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=199944"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199944\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=199944"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=199944"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=199944"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}