{"id":142785,"date":"2024-10-31T23:09:53","date_gmt":"2024-10-31T15:09:53","guid":{"rendered":"https:\/\/server.hk\/cnblog\/142785\/"},"modified":"2024-10-31T23:09:54","modified_gmt":"2024-10-31T15:09:54","slug":"sql-server-%e9%8c%af%e8%aa%a4-125-case-%e8%a1%a8%e9%81%94%e5%bc%8f%e5%8f%aa%e8%83%bd%e5%b5%8c%e5%a5%97%e5%88%b0-d-%e5%b1%a4%e3%80%82%e6%95%85%e9%9a%9c%e8%99%95%e7%90%86%e4%bf%ae%e5%be%a9%e6%94%af","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/142785\/","title":{"rendered":"SQL Server \u932f\u8aa4 125 Case \u8868\u9054\u5f0f\u53ea\u80fd\u5d4c\u5957\u5230 %d \u5c64\u3002\u6545\u969c\u8655\u7406\u4fee\u5fa9\u652f\u6301\u9060\u7a0b"},"content":{"rendered":"<h1 id=\"sql-server-%e9%8c%af%e8%aa%a4-125%ef%bc%9acase-%e8%a1%a8%e9%81%94%e5%bc%8f%e5%8f%aa%e8%83%bd%e5%b5%8c%e5%a5%97%e5%88%b0-d-%e5%b1%a4-ztyHkGyenR\">SQL Server \u932f\u8aa4 125\uff1aCase \u8868\u9054\u5f0f\u53ea\u80fd\u5d4c\u5957\u5230 %d \u5c64<\/h1>\n<p>\u5728\u4f7f\u7528 SQL Server \u9032\u884c\u6578\u64da\u67e5\u8a62\u548c\u64cd\u4f5c\u6642\uff0c\u958b\u767c\u8005\u53ef\u80fd\u6703\u9047\u5230\u5404\u7a2e\u932f\u8aa4\u4fe1\u606f\u3002\u5176\u4e2d\uff0c\u932f\u8aa4 125 \u662f\u4e00\u500b\u5e38\u898b\u7684\u554f\u984c\uff0c\u901a\u5e38\u8207 CASE \u8868\u9054\u5f0f\u7684\u5d4c\u5957\u5c64\u6578\u6709\u95dc\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u9019\u4e00\u932f\u8aa4\u7684\u6210\u56e0\u3001\u5f71\u97ff\u4ee5\u53ca\u89e3\u6c7a\u65b9\u6848\u3002<\/p>\n<h2 id=\"%e9%8c%af%e8%aa%a4-125-%e7%9a%84%e6%88%90%e5%9b%a0-ztyHkGyenR\">\u932f\u8aa4 125 \u7684\u6210\u56e0<\/h2>\n<p>SQL Server \u4e2d\u7684 CASE \u8868\u9054\u5f0f\u662f\u4e00\u7a2e\u689d\u4ef6\u8a9e\u53e5\uff0c\u5141\u8a31\u6839\u64da\u4e0d\u540c\u7684\u689d\u4ef6\u8fd4\u56de\u4e0d\u540c\u7684\u503c\u3002\u9019\u7a2e\u8868\u9054\u5f0f\u53ef\u4ee5\u5d4c\u5957\u4f7f\u7528\uff0c\u4f46 SQL Server \u5c0d\u5d4c\u5957\u5c64\u6578\u6709\u4e00\u5b9a\u7684\u9650\u5236\u3002\u7576\u5d4c\u5957\u5c64\u6578\u8d85\u904e\u9810\u8a2d\u7684\u6700\u5927\u503c\u6642\uff0c\u5c31\u6703\u51fa\u73fe\u932f\u8aa4 125\uff0c\u63d0\u793a\u300cCase \u8868\u9054\u5f0f\u53ea\u80fd\u5d4c\u5957\u5230 %d \u5c64\u300d\u3002<\/p>\n<p>\u5177\u9ad4\u4f86\u8aaa\uff0c\u9019\u500b\u932f\u8aa4\u901a\u5e38\u767c\u751f\u5728\u4ee5\u4e0b\u60c5\u6cc1\uff1a<\/p>\n<ul>\n<li>\u5728\u4e00\u500b CASE \u8868\u9054\u5f0f\u4e2d\u5d4c\u5957\u4e86\u904e\u591a\u7684 CASE \u8a9e\u53e5\u3002<\/li>\n<li>\u5728\u8907\u96dc\u7684\u67e5\u8a62\u4e2d\uff0c\u4f7f\u7528\u4e86\u591a\u5c64\u7684 CASE \u8868\u9054\u5f0f\uff0c\u5c0e\u81f4\u5c64\u6578\u8d85\u904e SQL Server \u7684\u9650\u5236\u3002<\/li>\n<li>\u5728\u4f7f\u7528\u52d5\u614b SQL \u6216\u5b58\u5132\u904e\u7a0b\u6642\uff0c\u672a\u80fd\u59a5\u5584\u7ba1\u7406 CASE \u8868\u9054\u5f0f\u7684\u5c64\u6578\u3002<\/li>\n<\/ul>\n<h2 id=\"%e9%8c%af%e8%aa%a4%e7%9a%84%e5%bd%b1%e9%9f%bf-ztyHkGyenR\">\u932f\u8aa4\u7684\u5f71\u97ff<\/h2>\n<p>\u7576\u51fa\u73fe\u932f\u8aa4 125 \u6642\uff0cSQL Server \u5c07\u7121\u6cd5\u57f7\u884c\u8a72\u67e5\u8a62\uff0c\u9019\u6703\u5c0e\u81f4\u61c9\u7528\u7a0b\u5e8f\u7684\u529f\u80fd\u53d7\u9650\uff0c\u5f71\u97ff\u7528\u6236\u9ad4\u9a57\u3002\u6b64\u5916\uff0c\u9019\u7a2e\u932f\u8aa4\u53ef\u80fd\u6703\u5c0e\u81f4\u6578\u64da\u8655\u7406\u7684\u5ef6\u9072\uff0c\u7279\u5225\u662f\u5728\u9700\u8981\u9032\u884c\u5927\u91cf\u6578\u64da\u67e5\u8a62\u7684\u60c5\u6cc1\u4e0b\u3002<\/p>\n<h2 id=\"%e8%a7%a3%e6%b1%ba%e6%96%b9%e6%a1%88-ztyHkGyenR\">\u89e3\u6c7a\u65b9\u6848<\/h2>\n<p>\u70ba\u4e86\u89e3\u6c7a SQL Server \u932f\u8aa4 125\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u63a1\u53d6\u4ee5\u4e0b\u5e7e\u7a2e\u65b9\u6cd5\uff1a<\/p>\n<h3 id=\"1-%e7%b0%a1%e5%8c%96-case-%e8%a1%a8%e9%81%94%e5%bc%8f-ztyHkGyenR\">1. \u7c21\u5316 CASE \u8868\u9054\u5f0f<\/h3>\n<p>\u9996\u5148\uff0c\u6aa2\u67e5 CASE \u8868\u9054\u5f0f\u7684\u7d50\u69cb\uff0c\u5617\u8a66\u7c21\u5316\u908f\u8f2f\u3002\u53ef\u4ee5\u5c07\u8907\u96dc\u7684 CASE \u8868\u9054\u5f0f\u62c6\u5206\u70ba\u591a\u500b\u7c21\u55ae\u7684\u8868\u9054\u5f0f\uff0c\u9019\u6a23\u53ef\u4ee5\u6e1b\u5c11\u5d4c\u5957\u5c64\u6578\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>\nSELECT \n    CASE \n        WHEN condition1 THEN result1\n        WHEN condition2 THEN \n            CASE \n                WHEN condition3 THEN result2\n                ELSE result3\n            END\n        ELSE result4\n    END AS Result\nFROM TableName;\n<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u8003\u616e\u5c07\u5167\u90e8\u7684 CASE \u8868\u9054\u5f0f\u63d0\u53d6\u5230\u5916\u90e8\u67e5\u8a62\u4e2d\uff0c\u6216\u4f7f\u7528\u5176\u4ed6\u908f\u8f2f\u7d50\u69cb\u4f86\u9054\u5230\u76f8\u540c\u7684\u76ee\u7684\u3002<\/p>\n<h3 id=\"2-%e4%bd%bf%e7%94%a8%e5%85%b6%e4%bb%96-sql-%e7%b5%90%e6%a7%8b-ztyHkGyenR\">2. \u4f7f\u7528\u5176\u4ed6 SQL \u7d50\u69cb<\/h3>\n<p>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u53ef\u4ee5\u8003\u616e\u4f7f\u7528\u5176\u4ed6 SQL \u7d50\u69cb\u4f86\u66ff\u4ee3 CASE \u8868\u9054\u5f0f\u3002\u4f8b\u5982\uff0c\u4f7f\u7528 JOIN \u6216\u5b50\u67e5\u8a62\u4f86\u8655\u7406\u689d\u4ef6\u908f\u8f2f\uff0c\u9019\u6a23\u53ef\u4ee5\u907f\u514d\u904e\u591a\u7684\u5d4c\u5957\u5c64\u6578\u3002<\/p>\n<pre><code>\nSELECT \n    t1.Column1,\n    t2.Column2\nFROM \n    Table1 t1\nJOIN \n    Table2 t2 ON t1.ID = t2.ID\nWHERE \n    (t1.Condition = 'Value1' AND t2.Condition = 'Value2') OR\n    (t1.Condition = 'Value3');\n<\/code><\/pre>\n<h3 id=\"3-%e5%a2%9e%e5%8a%a0%e5%b1%a4%e6%95%b8%e9%99%90%e5%88%b6-ztyHkGyenR\">3. \u589e\u52a0\u5c64\u6578\u9650\u5236<\/h3>\n<p>\u96d6\u7136\u4e0d\u5efa\u8b70\u9019\u6a23\u505a\uff0c\u4f46\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u53ef\u4ee5\u8003\u616e\u8abf\u6574 SQL Server \u7684\u914d\u7f6e\u4f86\u589e\u52a0 CASE \u8868\u9054\u5f0f\u7684\u5d4c\u5957\u5c64\u6578\u9650\u5236\u3002\u4e0d\u904e\uff0c\u9019\u9700\u8981\u8b39\u614e\u64cd\u4f5c\uff0c\u56e0\u70ba\u53ef\u80fd\u6703\u5f71\u97ff\u5230\u6574\u9ad4\u6027\u80fd\u548c\u7a69\u5b9a\u6027\u3002<\/p>\n<h2 id=\"%e7%b5%90%e8%ab%96-ztyHkGyenR\">\u7d50\u8ad6<\/h2>\n<p>SQL Server \u932f\u8aa4 125 \u662f\u4e00\u500b\u5e38\u898b\u7684\u554f\u984c\uff0c\u4e3b\u8981\u7531\u65bc CASE \u8868\u9054\u5f0f\u7684\u5d4c\u5957\u5c64\u6578\u904e\u591a\u6240\u5f15\u8d77\u3002\u901a\u904e\u7c21\u5316 CASE \u8868\u9054\u5f0f\u3001\u4f7f\u7528\u5176\u4ed6 SQL \u7d50\u69cb\u4ee5\u53ca\u8b39\u614e\u8abf\u6574\u5c64\u6578\u9650\u5236\uff0c\u53ef\u4ee5\u6709\u6548\u5730\u89e3\u6c7a\u9019\u4e00\u554f\u984c\u3002\u5c0d\u65bc\u958b\u767c\u8005\u4f86\u8aaa\uff0c\u7406\u89e3\u548c\u7ba1\u7406 CASE \u8868\u9054\u5f0f\u7684\u4f7f\u7528\u662f\u78ba\u4fdd SQL \u67e5\u8a62\u9ad8\u6548\u904b\u884c\u7684\u95dc\u9375\u3002<\/p>\n<p>\u5982\u9700\u9032\u4e00\u6b65\u4e86\u89e3\u6709\u95dc <a href=\"https:\/\/server.hk\">\u9999\u6e2f VPS<\/a> \u548c\u5176\u4ed6\u4f3a\u670d\u5668\u89e3\u6c7a\u65b9\u6848\u7684\u4fe1\u606f\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u89e3\u6c7a SQL Server \u932f\u8aa4 125\uff1aCase \u8868\u9054\u5f0f\u5d4c\u5957\u5c64\u6578\u9650\u5236\uff0c\u63d0\u4f9b\u6545\u969c\u8655\u7406\u548c\u9060\u7a0b\u652f\u6301\u7684\u4fee\u5fa9\u65b9\u6848\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-142785","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/142785","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=142785"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/142785\/revisions"}],"predecessor-version":[{"id":142786,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/142785\/revisions\/142786"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=142785"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=142785"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=142785"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}