{"id":168549,"date":"2024-11-06T13:18:19","date_gmt":"2024-11-06T05:18:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/168549\/"},"modified":"2024-11-06T13:18:20","modified_gmt":"2024-11-06T05:18:20","slug":"sql-%e4%b8%ad%e5%be%aa%e7%92%b0%e8%aa%9e%e5%8f%a5%e7%9a%84%e6%95%88%e6%9e%9c%e5%af%a6%e4%be%8b","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/168549\/","title":{"rendered":"SQL \u4e2d\u5faa\u74b0\u8a9e\u53e5\u7684\u6548\u679c\u5be6\u4f8b"},"content":{"rendered":"<h1 id=\"sql-%e4%b8%ad%e5%be%aa%e7%92%b0%e8%aa%9e%e5%8f%a5%e7%9a%84%e6%95%88%e6%9e%9c%e5%af%a6%e4%be%8b-BtqjaWqCUX\">SQL \u4e2d\u5faa\u74b0\u8a9e\u53e5\u7684\u6548\u679c\u5be6\u4f8b<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cSQL\uff08\u7d50\u69cb\u5316\u67e5\u8a62\u8a9e\u8a00\uff09\u662f\u4e00\u7a2e\u7528\u65bc\u67e5\u8a62\u548c\u64cd\u4f5c\u8cc7\u6599\u7684\u6a19\u6e96\u8a9e\u8a00\u3002\u5faa\u74b0\u8a9e\u53e5\u5728 SQL \u4e2d\u7684\u4f7f\u7528\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u91cf\u8cc7\u6599\u6642\uff0c\u80fd\u5920\u986f\u8457\u63d0\u9ad8\u6548\u7387\u548c\u9748\u6d3b\u6027\u3002\u672c\u6587\u5c07\u63a2\u8a0e SQL \u4e2d\u5faa\u74b0\u8a9e\u53e5\u7684\u57fa\u672c\u6982\u5ff5\u53ca\u5176\u6548\u679c\u5be6\u4f8b\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u597d\u5730\u7406\u89e3\u5176\u61c9\u7528\u5834\u666f\u3002<\/p>\n<h2 id=\"%e5%be%aa%e7%92%b0%e8%aa%9e%e5%8f%a5%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-BtqjaWqCUX\">\u5faa\u74b0\u8a9e\u53e5\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>\u5faa\u74b0\u8a9e\u53e5\u5141\u8a31\u958b\u767c\u8005\u5728 SQL \u4e2d\u91cd\u8907\u57f7\u884c\u4e00\u6bb5\u7a0b\u5f0f\u78bc\uff0c\u76f4\u5230\u6eff\u8db3\u7279\u5b9a\u689d\u4ef6\u70ba\u6b62\u3002\u9019\u5728\u9700\u8981\u5c0d\u591a\u689d\u8a18\u9304\u9032\u884c\u76f8\u540c\u64cd\u4f5c\u6642\u7279\u5225\u6709\u7528\u3002\u5e38\u898b\u7684\u5faa\u74b0\u8a9e\u53e5\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><strong>WHILE \u5faa\u74b0<\/strong>\uff1a\u7576\u689d\u4ef6\u70ba\u771f\u6642\uff0c\u91cd\u8907\u57f7\u884c\u4e00\u6bb5\u7a0b\u5f0f\u78bc\u3002<\/li>\n<li><strong>FOR \u5faa\u74b0<\/strong>\uff1a\u6839\u64da\u6307\u5b9a\u7684\u7bc4\u570d\u91cd\u8907\u57f7\u884c\u4e00\u6bb5\u7a0b\u5f0f\u78bc\u3002<\/li>\n<\/ul>\n<h2 id=\"sql-%e4%b8%ad%e7%9a%84-while-%e5%be%aa%e7%92%b0%e7%a4%ba%e4%be%8b-BtqjaWqCUX\">SQL \u4e2d\u7684 WHILE \u5faa\u74b0\u793a\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528 WHILE \u5faa\u74b0\u7684 SQL \u793a\u4f8b\uff0c\u8a72\u793a\u4f8b\u5c07\u5f9e\u4e00\u500b\u540d\u70ba <code>employees<\/code> \u7684\u8868\u4e2d\u9078\u53d6\u6240\u6709\u54e1\u5de5\u7684\u85aa\u6c34\uff0c\u4e26\u5c07\u5176\u589e\u52a0 10%\u3002<\/p>\n<pre><code>\nDECLARE @counter INT = 1;\nDECLARE @totalEmployees INT;\n\nSELECT @totalEmployees = COUNT(*) FROM employees;\n\nWHILE @counter &lt;= @totalEmployees\nBEGIN\n    UPDATE employees\n    SET salary = salary * 1.10\n    WHERE employee_id = @counter;\n\n    SET @counter = @counter + 1;\nEND\n<\/code><\/pre>\n<p>\u5728\u9019\u500b\u793a\u4f8b\u4e2d\uff0c\u6211\u5011\u9996\u5148\u8a08\u7b97\u51fa\u54e1\u5de5\u7684\u7e3d\u6578\uff0c\u7136\u5f8c\u4f7f\u7528 WHILE \u5faa\u74b0\u9010\u4e00\u66f4\u65b0\u6bcf\u4f4d\u54e1\u5de5\u7684\u85aa\u6c34\u3002\u9019\u7a2e\u65b9\u6cd5\u96d6\u7136\u7c21\u55ae\uff0c\u4f46\u5728\u8655\u7406\u5927\u91cf\u8cc7\u6599\u6642\u53ef\u80fd\u6703\u5c0e\u81f4\u6027\u80fd\u554f\u984c\u3002<\/p>\n<h2 id=\"sql-%e4%b8%ad%e7%9a%84-for-%e5%be%aa%e7%92%b0%e7%a4%ba%e4%be%8b-BtqjaWqCUX\">SQL \u4e2d\u7684 FOR \u5faa\u74b0\u793a\u4f8b<\/h2>\n<p>\u5728\u67d0\u4e9b SQL \u5be6\u73fe\u4e2d\uff0cFOR \u5faa\u74b0\u4e5f\u53ef\u4ee5\u7528\u4f86\u7c21\u5316\u64cd\u4f5c\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528 FOR \u5faa\u74b0\u7684\u793a\u4f8b\uff0c\u8a72\u793a\u4f8b\u5c07\u6240\u6709\u54e1\u5de5\u7684\u85aa\u6c34\u589e\u52a0 10%\u3002<\/p>\n<pre><code>\nDECLARE @employee_id INT;\n\nFOR @employee_id IN (SELECT employee_id FROM employees)\nBEGIN\n    UPDATE employees\n    SET salary = salary * 1.10\n    WHERE employee_id = @employee_id;\nEND\n<\/code><\/pre>\n<p>\u9019\u500b\u793a\u4f8b\u4e2d\uff0c\u6211\u5011\u4f7f\u7528 FOR \u5faa\u74b0\u4f86\u904d\u6b77\u6240\u6709\u54e1\u5de5\u7684 ID\uff0c\u4e26\u66f4\u65b0\u5176\u85aa\u6c34\u3002\u9019\u7a2e\u65b9\u6cd5\u6bd4 WHILE \u5faa\u74b0\u66f4\u70ba\u7c21\u6f54\uff0c\u4e14\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\u6027\u80fd\u66f4\u4f73\u3002<\/p>\n<h2 id=\"%e5%be%aa%e7%92%b0%e8%aa%9e%e5%8f%a5%e7%9a%84%e6%80%a7%e8%83%bd%e8%80%83%e9%87%8f-BtqjaWqCUX\">\u5faa\u74b0\u8a9e\u53e5\u7684\u6027\u80fd\u8003\u91cf<\/h2>\n<p>\u96d6\u7136\u5faa\u74b0\u8a9e\u53e5\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f46\u5728\u4f7f\u7528\u6642\u9700\u8981\u6ce8\u610f\u6027\u80fd\u554f\u984c\u3002\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u91cf\u8cc7\u6599\u6642\uff0c\u5faa\u74b0\u8a9e\u53e5\u53ef\u80fd\u6703\u5c0e\u81f4\u57f7\u884c\u6548\u7387\u4f4e\u4e0b\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u512a\u5316\u5efa\u8b70\uff1a<\/p>\n<ul>\n<li><strong>\u6279\u91cf\u64cd\u4f5c<\/strong>\uff1a\u76e1\u91cf\u4f7f\u7528\u6279\u91cf\u64cd\u4f5c\u4f86\u66ff\u4ee3\u9010\u884c\u8655\u7406\uff0c\u9019\u6a23\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u6027\u80fd\u3002<\/li>\n<li><strong>\u7d22\u5f15\u4f7f\u7528<\/strong>\uff1a\u78ba\u4fdd\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528\u9069\u7576\u7684\u7d22\u5f15\uff0c\u4ee5\u52a0\u5feb\u67e5\u8a62\u901f\u5ea6\u3002<\/li>\n<li><strong>\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u5faa\u74b0<\/strong>\uff1a\u5728\u53ef\u80fd\u7684\u60c5\u6cc1\u4e0b\uff0c\u4f7f\u7528\u96c6\u5408\u64cd\u4f5c\u4f86\u66ff\u4ee3\u5faa\u74b0\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-BtqjaWqCUX\">\u7e3d\u7d50<\/h2>\n<p>SQL \u4e2d\u7684\u5faa\u74b0\u8a9e\u53e5\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u80fd\u5920\u5e6b\u52a9\u958b\u767c\u8005\u5728\u8655\u7406\u8cc7\u6599\u6642\u63d0\u9ad8\u9748\u6d3b\u6027\u548c\u6548\u7387\u3002\u7136\u800c\uff0c\u4f7f\u7528\u5faa\u74b0\u8a9e\u53e5\u6642\u5fc5\u9808\u8b39\u614e\uff0c\u4ee5\u907f\u514d\u6027\u80fd\u554f\u984c\u3002\u900f\u904e\u9069\u7576\u7684\u512a\u5316\u548c\u6279\u91cf\u64cd\u4f5c\uff0c\u53ef\u4ee5\u6709\u6548\u63d0\u5347 SQL \u67e5\u8a62\u7684\u57f7\u884c\u6548\u7387\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u4e0d\u540c\u9700\u6c42\u7684\u5ba2\u6236\u3002\u7121\u8ad6\u662f <a href=\"https:\/\/server.hk\">\u4e91\u670d\u52a1\u5668<\/a> \u9084\u662f <a href=\"https:\/\/server.hk\">\u9999\u6e2f\u670d\u52a1\u5668<\/a>\uff0c\u6211\u5011\u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u53ef\u9760\u7684\u670d\u52d9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22 SQL \u4e2d\u5faa\u74b0\u8a9e\u53e5\u7684\u6548\u679c\u5be6\u4f8b\uff0c\u4e86\u89e3\u5982\u4f55\u6709\u6548\u5730\u8655\u7406\u91cd\u8907\u6578\u64da\u548c\u81ea\u52d5\u5316\u6578\u64da\u64cd\u4f5c\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-168549","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/168549","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=168549"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/168549\/revisions"}],"predecessor-version":[{"id":168550,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/168549\/revisions\/168550"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=168549"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=168549"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=168549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}