{"id":144129,"date":"2024-11-01T08:11:26","date_gmt":"2024-11-01T00:11:26","guid":{"rendered":"https:\/\/server.hk\/cnblog\/144129\/"},"modified":"2024-11-01T08:11:27","modified_gmt":"2024-11-01T00:11:27","slug":"transact-sql-%e8%ae%8a%e9%87%8f%e7%9a%84%e8%81%b2%e6%98%8e","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/144129\/","title":{"rendered":"Transact-SQL \u8b8a\u91cf\u7684\u8072\u660e"},"content":{"rendered":"<h1 id=\"transact-sql-%e8%ae%8a%e9%87%8f%e7%9a%84%e8%81%b2%e6%98%8e-QBXiMBkijq\">Transact-SQL \u8b8a\u91cf\u7684\u8072\u660e<\/h1>\n<p>\u5728 SQL Server \u4e2d\uff0cTransact-SQL\uff08T-SQL\uff09\u662f\u4e00\u7a2e\u64f4\u5c55\u7684 SQL \u8a9e\u8a00\uff0c\u63d0\u4f9b\u4e86\u8a31\u591a\u529f\u80fd\u4f86\u589e\u5f37\u6578\u64da\u5eab\u7684\u64cd\u4f5c\u80fd\u529b\u3002\u5176\u4e2d\uff0c\u8b8a\u91cf\u7684\u4f7f\u7528\u662f T-SQL \u4e2d\u4e00\u500b\u91cd\u8981\u7684\u6982\u5ff5\uff0c\u80fd\u5920\u5e6b\u52a9\u958b\u767c\u8005\u5728\u57f7\u884c\u67e5\u8a62\u6642\u5b58\u5132\u548c\u64cd\u4f5c\u6578\u64da\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e T-SQL \u4e2d\u8b8a\u91cf\u7684\u8072\u660e\u53ca\u5176\u4f7f\u7528\u65b9\u6cd5\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e8%ae%8a%e9%87%8f%ef%bc%9f-QBXiMBkijq\">\u4ec0\u9ebc\u662f\u8b8a\u91cf\uff1f<\/h2>\n<p>\u8b8a\u91cf\u662f\u7528\u4f86\u5b58\u5132\u6578\u64da\u7684\u547d\u540d\u5167\u5b58\u4f4d\u7f6e\u3002\u5728 T-SQL \u4e2d\uff0c\u8b8a\u91cf\u53ef\u4ee5\u7528\u4f86\u4fdd\u5b58\u55ae\u4e00\u503c\u6216\u8868\u683c\u6578\u64da\uff0c\u4e26\u5728\u67e5\u8a62\u904e\u7a0b\u4e2d\u9032\u884c\u64cd\u4f5c\u3002\u8b8a\u91cf\u7684\u4f7f\u7528\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8a62\u7684\u9748\u6d3b\u6027\u548c\u53ef\u8b80\u6027\u3002<\/p>\n<h2 id=\"%e8%ae%8a%e9%87%8f%e7%9a%84%e8%81%b2%e6%98%8e-QBXiMBkijq\">\u8b8a\u91cf\u7684\u8072\u660e<\/h2>\n<p>\u5728 T-SQL \u4e2d\uff0c\u8b8a\u91cf\u7684\u8072\u660e\u4f7f\u7528 <code>DECLARE<\/code> \u8a9e\u53e5\u3002\u8b8a\u91cf\u7684\u540d\u7a31\u5fc5\u9808\u4ee5 @ \u7b26\u865f\u958b\u982d\uff0c\u5f8c\u9762\u53ef\u4ee5\u8ddf\u96a8\u5b57\u6bcd\u3001\u6578\u5b57\u6216\u4e0b\u5283\u7dda\u3002\u8b8a\u91cf\u7684\u6578\u64da\u985e\u578b\u53ef\u4ee5\u662f SQL Server \u652f\u6301\u7684\u4efb\u4f55\u6578\u64da\u985e\u578b\uff0c\u5982 <code>INT<\/code>\u3001<code>VARCHAR<\/code>\u3001<code>DATETIME<\/code> \u7b49\u3002<\/p>\n<h3 id=\"%e8%ae%8a%e9%87%8f%e8%81%b2%e6%98%8e%e7%9a%84%e8%aa%9e%e6%b3%95-QBXiMBkijq\">\u8b8a\u91cf\u8072\u660e\u7684\u8a9e\u6cd5<\/h3>\n<pre><code>DECLARE @VariableName DataType;<\/code><\/pre>\n<h3 id=\"%e7%af%84%e4%be%8b-QBXiMBkijq\">\u7bc4\u4f8b<\/h3>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u7bc4\u4f8b\uff0c\u5c55\u793a\u5982\u4f55\u8072\u660e\u4e00\u500b\u6574\u6578\u8b8a\u91cf\u4e26\u8ce6\u503c\uff1a<\/p>\n<pre><code>DECLARE @Count INT;\nSET @Count = 10;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u8072\u660e\u4e86\u4e00\u500b\u540d\u70ba <code>@Count<\/code> \u7684\u6574\u6578\u8b8a\u91cf\uff0c\u4e26\u5c07\u5176\u503c\u8a2d\u7f6e\u70ba 10\u3002<\/p>\n<h2 id=\"%e8%ae%8a%e9%87%8f%e7%9a%84%e4%bd%bf%e7%94%a8-QBXiMBkijq\">\u8b8a\u91cf\u7684\u4f7f\u7528<\/h2>\n<p>\u8b8a\u91cf\u53ef\u4ee5\u5728 T-SQL \u67e5\u8a62\u4e2d\u7528\u65bc\u591a\u7a2e\u64cd\u4f5c\uff0c\u4f8b\u5982\u8a08\u7b97\u3001\u689d\u4ef6\u5224\u65b7\u548c\u5faa\u74b0\u7b49\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u4f7f\u7528\u5834\u666f\uff1a<\/p>\n<h3 id=\"%e8%a8%88%e7%ae%97-QBXiMBkijq\">\u8a08\u7b97<\/h3>\n<p>\u8b8a\u91cf\u53ef\u4ee5\u7528\u4f86\u5b58\u5132\u8a08\u7b97\u7d50\u679c\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>DECLARE @TotalSales DECIMAL(10, 2);\nSET @TotalSales = (SELECT SUM(SalesAmount) FROM Sales);<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u8a08\u7b97\u4e86 <code>Sales<\/code> \u8868\u4e2d\u6240\u6709\u92b7\u552e\u91d1\u984d\u7684\u7e3d\u548c\uff0c\u4e26\u5c07\u7d50\u679c\u5b58\u5132\u5728 <code>@TotalSales<\/code> \u8b8a\u91cf\u4e2d\u3002<\/p>\n<h3 id=\"%e6%a2%9d%e4%bb%b6%e5%88%a4%e6%96%b7-QBXiMBkijq\">\u689d\u4ef6\u5224\u65b7<\/h3>\n<p>\u8b8a\u91cf\u4e5f\u53ef\u4ee5\u7528\u65bc\u689d\u4ef6\u5224\u65b7\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>DECLARE @Status VARCHAR(10);\nSET @Status = 'Active';\n\nIF @Status = 'Active'\nBEGIN\n    PRINT 'The status is active.';\nEND<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u6839\u64da\u8b8a\u91cf <code>@Status<\/code> \u7684\u503c\u4f86\u6c7a\u5b9a\u662f\u5426\u6253\u5370\u4e00\u689d\u6d88\u606f\u3002<\/p>\n<h3 id=\"%e5%be%aa%e7%92%b0-QBXiMBkijq\">\u5faa\u74b0<\/h3>\n<p>\u8b8a\u91cf\u9084\u53ef\u4ee5\u7528\u65bc\u5faa\u74b0\u7d50\u69cb\u4e2d\uff0c\u4f8b\u5982\uff1a<\/p>\n<pre><code>DECLARE @Counter INT;\nSET @Counter = 1;\n\nWHILE @Counter &lt;= 5\nBEGIN\n    PRINT @Counter;\n    SET @Counter = @Counter + 1;\nEND<\/code><\/pre>\n<p>\u9019\u6bb5\u4ee3\u78bc\u5c07\u6253\u5370\u5f9e 1 \u5230 5 \u7684\u6578\u5b57\uff0c\u5c55\u793a\u4e86\u5982\u4f55\u4f7f\u7528\u8b8a\u91cf\u4f86\u63a7\u5236\u5faa\u74b0\u7684\u57f7\u884c\u3002<\/p>\n<h2 id=\"%e7%b5%90%e8%ab%96-QBXiMBkijq\">\u7d50\u8ad6<\/h2>\n<p>\u5728 T-SQL \u4e2d\uff0c\u8b8a\u91cf\u7684\u8072\u660e\u548c\u4f7f\u7528\u662f\u6578\u64da\u5eab\u64cd\u4f5c\u4e2d\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u90e8\u5206\u3002\u901a\u904e\u5408\u7406\u5730\u4f7f\u7528\u8b8a\u91cf\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8a62\u7684\u9748\u6d3b\u6027\u548c\u53ef\u8b80\u6027\uff0c\u5f9e\u800c\u66f4\u6709\u6548\u5730\u8655\u7406\u6578\u64da\u3002\u7121\u8ad6\u662f\u5728\u8a08\u7b97\u3001\u689d\u4ef6\u5224\u65b7\u9084\u662f\u5faa\u74b0\u64cd\u4f5c\u4e2d\uff0c\u8b8a\u91cf\u90fd\u80fd\u767c\u63ee\u91cd\u8981\u4f5c\u7528\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u670d\u52d9\u6709\u8208\u8da3\uff0c\u6216\u60f3\u4e86\u89e3\u66f4\u591a\u95dc\u65bc <a href=\"https:\/\/server.hk\">\u4e91\u670d\u52a1\u5668<\/a> \u7684\u8cc7\u8a0a\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u8a73\u7d30\u8cc7\u6599\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3Transact-SQL\u4e2d\u8b8a\u91cf\u7684\u8072\u660e\u65b9\u6cd5\uff0c\u5b78\u7fd2\u5982\u4f55\u6709\u6548\u4f7f\u7528\u8b8a\u91cf\u4f86\u63d0\u5347SQL\u67e5\u8a62\u7684\u9748\u6d3b\u6027\u548c\u53ef\u8b80\u6027\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-144129","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/144129","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=144129"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/144129\/revisions"}],"predecessor-version":[{"id":144130,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/144129\/revisions\/144130"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=144129"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=144129"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=144129"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}