{"id":806,"date":"2025-01-11T00:21:42","date_gmt":"2025-01-10T16:21:42","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=806"},"modified":"2025-01-11T00:21:42","modified_gmt":"2025-01-10T16:21:42","slug":"%e5%a6%82%e4%bd%95%e6%9c%89%e6%95%88%e7%9a%84%e9%81%bf%e5%85%8d-sql-%e5%8f%8d%e6%a8%a1%e5%bc%8f%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/01\/11\/%e5%a6%82%e4%bd%95%e6%9c%89%e6%95%88%e7%9a%84%e9%81%bf%e5%85%8d-sql-%e5%8f%8d%e6%a8%a1%e5%bc%8f%ef%bc%9f\/","title":{"rendered":"\u5982\u4f55\u6709\u6548\u7684\u907f\u514d SQL \u53cd\u6a21\u5f0f\uff1f"},"content":{"rendered":"\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">\u5728\u6570\u636e\u8bbf\u95ee\u5c42\u4e2d\uff0c\u907f\u514d\u5e38\u89c1\u7684 SQL \u53cd\u6a21\u5f0f\u5bf9\u4e8e\u63d0\u9ad8\u5e94\u7528\u7a0b\u5e8f\u7684\u6027\u80fd\u3001\u5b89\u5168\u6027\u3001\u53ef\u7ef4\u62a4\u6027\u548c\u53ef\u6269\u5c55\u6027\u81f3\u5173\u91cd\u8981\u3002SQL \u53cd\u6a21\u5f0f\u662f\u6307\u5728\u6570\u636e\u5e93\u67e5\u8be2\u548c\u64cd\u4f5c\u4e2d\u4e0d\u5408\u7406\u7684\u8bbe\u8ba1\u6216\u5b9e\u8df5\uff0c\u901a\u5e38\u4f1a\u5bfc\u81f4\u6027\u80fd\u95ee\u9898\u3001\u6570\u636e\u4e0d\u4e00\u81f4\u3001\u5b89\u5168\u6f0f\u6d1e\u7b49\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u89c1\u7684 SQL \u53cd\u6a21\u5f0f\uff0c\u4ee5\u53ca\u5982\u4f55\u907f\u514d\u5b83\u4eec\uff1a<\/p>\n<\/blockquote>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">1. **SELECT ***<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528 <code>SELECT *<\/code> \u4f1a\u68c0\u7d22\u6240\u6709\u5217\u7684\u6570\u636e\uff0c\u53ef\u80fd\u5bfc\u81f4\u4e0d\u5fc5\u8981\u7684\u6570\u636e\u52a0\u8f7d\uff0c\u589e\u52a0\u6570\u636e\u5e93\u8d1f\u62c5\uff0c\u964d\u4f4e\u6027\u80fd\uff0c\u5c24\u5176\u662f\u5728\u6709\u5927\u91cf\u5b57\u6bb5\u6216\u8bb0\u5f55\u7684\u8868\u65f6\u3002\u6b64\u5916\uff0c\u5b83\u8fd8\u53ef\u80fd\u5bfc\u81f4\u5c06\u6765\u4fee\u6539\u8868\u7ed3\u6784\u65f6\u51fa\u73b0\u95ee\u9898\uff08\u5982\u679c\u589e\u52a0\u6216\u5220\u9664\u4e86\u5217\uff0c\u53ef\u80fd\u4f1a\u5f71\u54cd\u5e94\u7528\u7a0b\u5e8f\u884c\u4e3a\uff09\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u660e\u786e\u6307\u5b9a\u9700\u8981\u7684\u5217<\/strong>\uff1a\u59cb\u7ec8\u53ea\u9009\u62e9\u4f60\u9700\u8981\u7684\u5217\uff0c\u4ee5\u51cf\u5c11\u4e0d\u5fc5\u8981\u7684\u6570\u636e\u4f20\u8f93\u548c\u8ba1\u7b97\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4e0d\u63a8\u8350\nSELECT * FROM Employees;\n\n-- \u63a8\u8350\nSELECT EmployeeID, Name, Department FROM Employees;<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u8fc7\u5ea6\u4f7f\u7528\u8054\u63a5\uff08JOIN\uff09<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fc7\u5ea6\u4f7f\u7528\u590d\u6742\u7684 <code>JOIN<\/code> \u67e5\u8be2\uff0c\u5c24\u5176\u662f\u5728\u6570\u636e\u91cf\u5927\u7684\u60c5\u51b5\u4e0b\uff0c\u4f1a\u5bfc\u81f4\u6027\u80fd\u95ee\u9898\u3002<code>JOIN<\/code> \u4f1a\u589e\u52a0\u67e5\u8be2\u7684\u590d\u6742\u5ea6\uff0c\u5c24\u5176\u662f\u591a\u4e2a\u8868\u7684 <code>INNER JOIN<\/code> \u6216 <code>LEFT JOIN<\/code> \u65f6\uff0c\u5982\u679c\u8868\u4e2d\u6709\u5927\u91cf\u6570\u636e\uff0c\u53ef\u80fd\u4f1a\u663e\u8457\u589e\u52a0\u67e5\u8be2\u65f6\u95f4\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4f18\u5316 JOIN \u67e5\u8be2<\/strong>\uff1a\u53ea\u5728\u5fc5\u8981\u65f6\u4f7f\u7528 <code>JOIN<\/code>\uff0c\u5e76\u4e14\u53ea\u5bf9\u9700\u8981\u7684\u5b57\u6bb5\u8fdb\u884c <code>JOIN<\/code>\u3002<\/li>\n\n\n\n<li><strong>\u4f7f\u7528\u9002\u5f53\u7684\u7d22\u5f15<\/strong>\uff1a\u786e\u4fdd\u8868\u4e4b\u95f4\u7684\u8054\u63a5\u5217\uff08\u901a\u5e38\u662f\u4e3b\u952e\u548c\u5916\u952e\uff09\u6709\u9002\u5f53\u7684\u7d22\u5f15\u3002<\/li>\n\n\n\n<li><strong>\u62c6\u5206\u590d\u6742\u67e5\u8be2<\/strong>\uff1a\u5bf9\u4e8e\u975e\u5e38\u590d\u6742\u7684\u67e5\u8be2\uff0c\u8003\u8651\u62c6\u5206\u4e3a\u591a\u4e2a\u7b80\u5355\u7684\u67e5\u8be2\uff0c\u5e76\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u8fdb\u884c\u5904\u7406\uff0c\u51cf\u5c11\u6570\u636e\u5e93\u7684\u8d1f\u62c5\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4e0d\u63a8\u8350\nSELECT * \nFROM Orders o \nJOIN Customers c ON o.CustomerID = c.CustomerID \nJOIN Employees e ON o.EmployeeID = e.EmployeeID \nJOIN Products p ON o.ProductID = p.ProductID;\n\n-- \u63a8\u8350\uff1a\u62c6\u5206\u67e5\u8be2\uff0c\u907f\u514d\u65e0\u610f\u4e49\u7684 JOIN\nSELECT * FROM Orders WHERE OrderID = 123;  \nSELECT * FROM Customers WHERE CustomerID = 123;<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u91cd\u590d\u67e5\u8be2\uff08N+1 \u67e5\u8be2\u95ee\u9898\uff09<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">N+1 \u67e5\u8be2\u95ee\u9898\u53d1\u751f\u5728\u4f60\u5728\u4e00\u4e2a\u67e5\u8be2\u4e2d\u83b7\u53d6\u4e86\u591a\u6761\u8bb0\u5f55\uff08\u4f8b\u5982\u83b7\u53d6\u591a\u4e2a\u7528\u6237\uff09\uff0c\u7136\u540e\u9488\u5bf9\u6bcf\u4e00\u6761\u8bb0\u5f55\u53d1\u51fa\u989d\u5916\u7684\u67e5\u8be2\u8bf7\u6c42\u3002\u8fd9\u79cd\u65b9\u5f0f\u4f1a\u5bfc\u81f4\u5927\u91cf\u5197\u4f59\u67e5\u8be2\uff0c\u6781\u5927\u5730\u964d\u4f4e\u6027\u80fd\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4f7f\u7528 JOIN \u6216\u6279\u91cf\u67e5\u8be2<\/strong>\uff1a\u901a\u8fc7\u4e00\u6b21\u6027\u83b7\u53d6\u6240\u9700\u7684\u6240\u6709\u6570\u636e\uff0c\u907f\u514d\u4e3a\u6bcf\u4e00\u6761\u8bb0\u5f55\u5355\u72ec\u67e5\u8be2\u3002<\/li>\n\n\n\n<li><strong>\u6279\u91cf\u83b7\u53d6\u76f8\u5173\u6570\u636e<\/strong>\uff1a\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\u5bf9\u9700\u8981\u7684\u6570\u636e\u8fdb\u884c\u5408\u5e76\uff0c\u907f\u514d\u91cd\u590d\u67e5\u8be2\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u9519\u8bef\u793a\u4f8b\uff1a\u4e00\u6b21\u67e5\u8be2\u83b7\u5f97\u6240\u6709\u7528\u6237\uff0c\u7136\u540e\u5bf9\u6bcf\u4e2a\u7528\u6237\u5355\u72ec\u67e5\u8be2\u4ed6\u4eec\u7684\u8ba2\u5355\nforeach (var user in users)\n{\n    var orders = dbContext.Orders.Where(o =&gt; o.UserId == user.Id).ToList();\n}\n\n\/\/ \u63a8\u8350\uff1a\u901a\u8fc7 JOIN \u6216\u6279\u91cf\u67e5\u8be2\u4e00\u6b21\u6027\u83b7\u5f97\u6240\u6709\u6570\u636e\nvar userOrders = dbContext.Users\n                          .Join(dbContext.Orders, u =&gt; u.Id, o =&gt; o.UserId, (u, o) =&gt; new { u, o })\n                          .ToList();<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">4. <strong>\u672a\u4f7f\u7528\u7d22\u5f15<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u6ca1\u6709\u4e3a\u7ecf\u5e38\u7528\u4e8e\u67e5\u8be2\u3001\u6392\u5e8f\u3001\u8fc7\u6ee4\u7684\u5217\u521b\u5efa\u7d22\u5f15\uff0c\u53ef\u80fd\u5bfc\u81f4\u5168\u8868\u626b\u63cf\uff0c\u4ece\u800c\u5927\u5927\u964d\u4f4e\u67e5\u8be2\u6027\u80fd\u3002\u7d22\u5f15\u80fd\u663e\u8457\u63d0\u9ad8\u68c0\u7d22\u6570\u636e\u7684\u901f\u5ea6\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u521b\u5efa\u9002\u5f53\u7684\u7d22\u5f15<\/strong>\uff1a\u5bf9\u5e38\u7528\u7684\u67e5\u8be2\u6761\u4ef6\uff08\u5982 WHERE\u3001JOIN\u3001ORDER BY \u4e2d\u7684\u5217\uff09\u521b\u5efa\u7d22\u5f15\uff0c\u7279\u522b\u662f\u90a3\u4e9b\u6d89\u53ca\u8303\u56f4\u67e5\u8be2\u6216\u6392\u5e8f\u7684\u5217\u3002<\/li>\n\n\n\n<li><strong>\u907f\u514d\u8fc7\u591a\u7684\u7d22\u5f15<\/strong>\uff1a\u867d\u7136\u7d22\u5f15\u80fd\u63d0\u9ad8\u67e5\u8be2\u901f\u5ea6\uff0c\u4f46\u8fc7\u591a\u7684\u7d22\u5f15\u4f1a\u589e\u52a0\u6570\u636e\u63d2\u5165\u3001\u66f4\u65b0\u548c\u5220\u9664\u7684\u8d1f\u62c5\u3002\u56e0\u6b64\uff0c\u8981\u6839\u636e\u5b9e\u9645\u67e5\u8be2\u60c5\u51b5\u521b\u5efa\u5fc5\u8981\u7684\u7d22\u5f15\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u793a\u4f8b\uff1a\u5728 `UserID` \u4e0a\u521b\u5efa\u7d22\u5f15\nCREATE INDEX idx_UserID ON Orders(UserID);<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">5. <strong>\u5728\u67e5\u8be2\u4e2d\u4f7f\u7528\u4e0d\u5fc5\u8981\u7684\u5b50\u67e5\u8be2<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u67e5\u8be2\u4e2d\u4f7f\u7528\u5d4c\u5957\u7684\u5b50\u67e5\u8be2\uff0c\u5c24\u5176\u662f\u5982\u679c\u6ca1\u6709\u5fc5\u8981\u65f6\uff0c\u4f1a\u589e\u52a0\u67e5\u8be2\u7684\u590d\u6742\u6027\u548c\u6267\u884c\u65f6\u95f4\u3002\u5b50\u67e5\u8be2\u901a\u5e38\u4f1a\u5f15\u53d1\u989d\u5916\u7684\u8ba1\u7b97\u548c\u5185\u5b58\u6d88\u8017\uff0c\u5c24\u5176\u662f\u5728\u6570\u636e\u91cf\u5927\u7684\u65f6\u5019\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u5b50\u67e5\u8be2<\/strong>\uff1a\u901a\u8fc7 <code>JOIN<\/code> \u6216\u5176\u4ed6\u66f4\u9ad8\u6548\u7684\u65b9\u6cd5\u6765\u66ff\u4ee3\u4e0d\u5fc5\u8981\u7684\u5b50\u67e5\u8be2\uff0c\u5c3d\u53ef\u80fd\u51cf\u5c11\u6570\u636e\u5904\u7406\u7684\u5c42\u6b21\u3002<\/li>\n\n\n\n<li><strong>\u4f7f\u7528 <code>EXISTS<\/code> \u6216 <code>IN<\/code> \u6765\u66ff\u4ee3\u5b50\u67e5\u8be2<\/strong>\uff0c\u5f53\u5408\u9002\u65f6\u53ef\u4ee5\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u67e5\u8be2\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4e0d\u63a8\u8350\uff1a\u5b50\u67e5\u8be2\nSELECT Name \nFROM Employees \nWHERE EmployeeID IN (SELECT EmployeeID FROM Orders WHERE OrderAmount &gt; 100);\n\n-- \u63a8\u8350\uff1a\u4f7f\u7528 JOIN\nSELECT e.Name \nFROM Employees e\nJOIN Orders o ON e.EmployeeID = o.EmployeeID\nWHERE o.OrderAmount &gt; 100;<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">6. <strong>\u6570\u636e\u5197\u4f59\u548c\u53cd\u8303\u5f0f\u5316<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u53cd\u8303\u5f0f\u5316\u662f\u6307\u5728\u6570\u636e\u5e93\u8bbe\u8ba1\u4e2d\u6545\u610f\u5c06\u6570\u636e\u5197\u4f59\uff0c\u4ee5\u51cf\u5c11\u67e5\u8be2\u4e2d\u7684\u8054\u63a5\uff08<code>JOIN<\/code>\uff09\u3002\u8fd9\u79cd\u505a\u6cd5\u867d\u7136\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\u53ef\u80fd\u63d0\u9ad8\u67e5\u8be2\u6027\u80fd\uff0c\u4f46\u4f1a\u589e\u52a0\u6570\u636e\u4e00\u81f4\u6027\u95ee\u9898\u548c\u66f4\u65b0\u65f6\u7684\u590d\u6742\u5ea6\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u907f\u514d\u6570\u636e\u5197\u4f59<\/strong>\uff1a\u4fdd\u6301\u6570\u636e\u5e93\u7684\u8303\u5f0f\u5316\uff0c\u786e\u4fdd\u6570\u636e\u4e00\u81f4\u6027\u548c\u6613\u4e8e\u7ef4\u62a4\u3002\u6839\u636e\u5b9e\u9645\u60c5\u51b5\u9002\u5f53\u4f7f\u7528\u7d22\u5f15\u6765\u4f18\u5316\u67e5\u8be2\u6027\u80fd\uff0c\u800c\u4e0d\u4f9d\u8d56\u5197\u4f59\u6570\u636e\u3002<\/li>\n\n\n\n<li><strong>\u5408\u9002\u7684\u53cd\u8303\u5f0f\u5316<\/strong>\uff1a\u5728\u660e\u786e\u7684\u6027\u80fd\u9700\u6c42\u4e0b\uff0c\u7ecf\u8fc7\u4e25\u683c\u7684\u6027\u80fd\u6d4b\u8bd5\u540e\uff0c\u8003\u8651\u9002\u5ea6\u7684\u53cd\u8303\u5f0f\u5316\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">7. <strong>\u786c\u7f16\u7801 SQL \u67e5\u8be2<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u786c\u7f16\u7801\u7684 SQL \u67e5\u8be2\u4f1a\u4f7f\u5f97\u4ee3\u7801\u53d8\u5f97\u96be\u4ee5\u7ef4\u62a4\u548c\u6269\u5c55\uff0c\u7279\u522b\u662f\u5728\u67e5\u8be2\u4e2d\u5d4c\u5165\u4e86\u8868\u540d\u3001\u5217\u540d\u7b49\u3002\u5982\u679c\u8868\u7ed3\u6784\u6216\u5217\u540d\u53d1\u751f\u53d8\u5316\uff0c\u67e5\u8be2\u53ef\u80fd\u4f1a\u5931\u8d25\uff0c\u589e\u52a0\u4e86\u4ee3\u7801\u7684\u8026\u5408\u5ea6\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u53c2\u6570\u5316\u67e5\u8be2<\/strong>\uff1a\u4f7f\u7528\u53c2\u6570\u5316\u67e5\u8be2\u6216\u5b58\u50a8\u8fc7\u7a0b\uff0c\u4ee5\u907f\u514d SQL \u6ce8\u5165\u653b\u51fb\uff0c\u5e76\u4f7f\u67e5\u8be2\u66f4\u52a0\u7075\u6d3b\u548c\u5b89\u5168\u3002<\/li>\n\n\n\n<li><strong>\u907f\u514d\u786c\u7f16\u7801\u8868\u540d\u6216\u5217\u540d<\/strong>\uff1a\u5982\u679c\u53ef\u80fd\uff0c\u907f\u514d\u5728\u67e5\u8be2\u4e2d\u786c\u7f16\u7801\u8868\u540d\u6216\u5217\u540d\u3002\u53ef\u4ee5\u901a\u8fc7\u914d\u7f6e\u6216\u52a8\u6001\u6784\u5efa\u67e5\u8be2\u6765\u63d0\u9ad8\u4ee3\u7801\u7684\u53ef\u7ef4\u62a4\u6027\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u4e0d\u63a8\u8350\uff1a\u786c\u7f16\u7801 SQL \u67e5\u8be2\nstring sql = \"SELECT * FROM Employees WHERE Name = '\" + userName + \"'\";\n\n\/\/ \u63a8\u8350\uff1a\u53c2\u6570\u5316\u67e5\u8be2\nstring sql = \"SELECT * FROM Employees WHERE Name = @userName\";\nSqlCommand cmd = new SqlCommand(sql, conn);\ncmd.Parameters.AddWithValue(\"@userName\", userName);<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">8. <strong>\u5ffd\u89c6 SQL \u6ce8\u5165\u653b\u51fb<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u6ca1\u6709\u4f7f\u7528\u53c2\u6570\u5316\u67e5\u8be2\u6216\u5b58\u50a8\u8fc7\u7a0b\u5bb9\u6613\u5bfc\u81f4 SQL \u6ce8\u5165\u653b\u51fb\uff0c\u653b\u51fb\u8005\u53ef\u4ee5\u901a\u8fc7\u8f93\u5165\u6076\u610f\u7684 SQL \u8bed\u53e5\u6765\u64cd\u63a7\u6570\u636e\u5e93\uff0c\u6cc4\u9732\u6570\u636e\u6216\u5220\u9664\u6570\u636e\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4f7f\u7528\u53c2\u6570\u5316\u67e5\u8be2\u6216\u5b58\u50a8\u8fc7\u7a0b<\/strong>\uff1a\u59cb\u7ec8\u4f7f\u7528\u53c2\u6570\u5316\u67e5\u8be2\u6765\u907f\u514d SQL \u6ce8\u5165\u653b\u51fb\uff0c\u4e0d\u8981\u76f4\u63a5\u5c06\u7528\u6237\u8f93\u5165\u62fc\u63a5\u5230 SQL \u67e5\u8be2\u4e2d\u3002<\/li>\n\n\n\n<li><strong>\u9a8c\u8bc1\u548c\u6e05\u7406\u7528\u6237\u8f93\u5165<\/strong>\uff1a\u5c3d\u53ef\u80fd\u5bf9\u7528\u6237\u8f93\u5165\u8fdb\u884c\u9a8c\u8bc1\u548c\u6e05\u7406\uff0c\u9650\u5236\u7528\u6237\u8f93\u5165\u7684\u7c7b\u578b\u548c\u8303\u56f4\uff0c\u51cf\u5c11\u653b\u51fb\u9762\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u4e0d\u63a8\u8350\uff1a\u62fc\u63a5\u67e5\u8be2\nstring sql = \"SELECT * FROM Users WHERE Username = '\" + username + \"' AND Password = '\" + password + \"'\";\n\n\/\/ \u63a8\u8350\uff1a\u53c2\u6570\u5316\u67e5\u8be2\nstring sql = \"SELECT * FROM Users WHERE Username = @username AND Password = @password\";\nSqlCommand cmd = new SqlCommand(sql, conn);\ncmd.Parameters.AddWithValue(\"@username\", username);\ncmd.Parameters.AddWithValue(\"@password\", password);<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">9. <strong>\u4e0d\u8003\u8651\u4e8b\u52a1\u7ba1\u7406<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u5ffd\u89c6\u4e8b\u52a1\u7ba1\u7406\u53ef\u80fd\u4f1a\u5bfc\u81f4\u6570\u636e\u5e93\u64cd\u4f5c\u7684\u4e0d\u4e00\u81f4\u6027\u3002\u4f8b\u5982\uff0c\u5728\u591a\u6761 SQL \u8bed\u53e5\u7684\u6279\u91cf\u64cd\u4f5c\u4e2d\uff0c\u5982\u679c\u4e00\u4e2a\u64cd\u4f5c\u5931\u8d25\uff0c\u5176\u4ed6\u64cd\u4f5c\u53ef\u80fd\u4f1a\u5f71\u54cd\u6570\u636e\u5e93\u7684\u72b6\u6001\uff0c\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4f7f\u7528\u4e8b\u52a1<\/strong>\uff1a\u5bf9\u4e8e\u6d89\u53ca\u591a\u4e2a\u6570\u636e\u4fee\u6539\u64cd\u4f5c\u7684\u67e5\u8be2\uff0c\u59cb\u7ec8\u4f7f\u7528\u4e8b\u52a1\u6765\u786e\u4fdd\u539f\u5b50\u6027\u3002\u4e8b\u52a1\u53ef\u4ee5\u786e\u4fdd\u8981\u4e48\u6240\u6709\u64cd\u4f5c\u6210\u529f\uff0c\u8981\u4e48\u5728\u51fa\u9519\u65f6\u56de\u6eda\u64cd\u4f5c\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>using (SqlTransaction transaction = conn.BeginTransaction())\n{\n    try\n    {\n        SqlCommand cmd1 = new SqlCommand(\"INSERT INTO Orders (OrderID) VALUES (1)\", conn, transaction);\n        cmd1.ExecuteNonQuery();\n\n        SqlCommand cmd2 = new SqlCommand(\"INSERT INTO OrderDetails (OrderID, ProductID) VALUES (1, 1)\", conn, transaction);\n        cmd2.ExecuteNonQuery();\n\n        \/\/ \u63d0\u4ea4\u4e8b\u52a1\n        transaction.Commit();\n    }\n    catch\n    {\n        \/\/ \u5982\u679c\u51fa\u73b0\u9519\u8bef\uff0c\u56de\u6eda\u4e8b\u52a1\n        transaction.Rollback();\n    }\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">10. <strong>\u6ca1\u6709\u8003\u8651\u67e5\u8be2\u6027\u80fd\uff08\u5927\u6570\u636e\u91cf\u4e0b\u7684\u67e5\u8be2\uff09<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u67e5\u8be2\u6d89\u53ca\u5927\u6570\u636e\u91cf\u65f6\uff0c\u5982\u679c\u6ca1\u6709\u9002\u5f53\u7684\u4f18\u5316\u63aa\u65bd\uff08\u4f8b\u5982\u7d22\u5f15\u3001\u5206\u9875\u7b49\uff09\uff0c\u67e5\u8be2\u53ef\u80fd\u4f1a\u975e\u5e38\u7f13\u6162\uff0c\u5f71\u54cd\u7cfb\u7edf\u7684\u54cd\u5e94\u65f6\u95f4\u548c\u6574\u4f53\u6027\u80fd\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5206\u9875\u67e5\u8be2<\/strong>\uff1a\u5bf9\u4e8e\u5927\u6570\u636e\u96c6\uff0c\u4f7f\u7528\u5206\u9875\u6280\u672f\u6765\u9650\u5236\u4e00\u6b21\u67e5\u8be2\u8fd4\u56de\u7684\u8bb0\u5f55\u6570\uff0c\u907f\u514d\u4e00\u6b21\u52a0\u8f7d\u8fc7\u591a\u6570\u636e\u3002<\/li>\n\n\n\n<li><strong>\u5408\u9002\u7684\u7d22\u5f15<\/strong>\uff1a\u4e3a\u7ecf\u5e38\u67e5\u8be2\u7684\u5217\u521b\u5efa\u7d22\u5f15\uff0c\u4ee5\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\u3002\u7279\u522b\u662f WHERE \u5b50\u53e5\u4e2d\u4f7f\u7528\u7684\u5b57\u6bb5\u3001JOIN \u7684\u5b57\u6bb5\u3001ORDER BY \u4e2d\u6392\u5e8f\u7684\u5b57\u6bb5\u7b49\u3002<\/li>\n\n\n\n<li><strong>\u907f\u514d\u5168\u8868\u626b\u63cf<\/strong>\uff1a\u5982\u679c\u67e5\u8be2\u6ca1\u6709\u5408\u9002\u7684\u7d22\u5f15\uff0c\u6570\u636e\u5e93\u901a\u5e38\u4f1a\u6267\u884c\u5168\u8868\u626b\u63cf\uff0c\u6781\u5927\u5730\u5f71\u54cd\u6027\u80fd\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u5206\u9875\u67e5\u8be2\u793a\u4f8b\uff08\u4f7f\u7528 OFFSET-FETCH\uff09\nSELECT Name, Age\nFROM Employees\nORDER BY Name\nOFFSET 0 ROWS FETCH NEXT 10 ROWS ONLY;<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">11. <strong>\u8fc7\u5ea6\u4f9d\u8d56\u5b58\u50a8\u8fc7\u7a0b<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fc7\u5ea6\u4f9d\u8d56\u5b58\u50a8\u8fc7\u7a0b\u53ef\u80fd\u5bfc\u81f4\u903b\u8f91\u96c6\u4e2d\u5728\u6570\u636e\u5e93\u7aef\uff0c\u964d\u4f4e\u4e86\u5e94\u7528\u7a0b\u5e8f\u7684\u7075\u6d3b\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u3002\u6b64\u5916\uff0c\u5982\u679c\u5b58\u50a8\u8fc7\u7a0b\u8bbe\u8ba1\u4e0d\u5f53\uff0c\u4e5f\u4f1a\u589e\u52a0\u6570\u636e\u5e93\u7684\u8d1f\u62c5\uff0c\u5f71\u54cd\u6027\u80fd\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5206\u79bb\u903b\u8f91<\/strong>\uff1a\u5c3d\u91cf\u5c06\u4e1a\u52a1\u903b\u8f91\u4fdd\u7559\u5728\u5e94\u7528\u7a0b\u5e8f\u4e2d\uff0c\u800c\u4e0d\u662f\u5c06\u6240\u6709\u903b\u8f91\u653e\u5165\u5b58\u50a8\u8fc7\u7a0b\u4e2d\u3002\u6570\u636e\u5e93\u5e94\u66f4\u591a\u5730\u4e13\u6ce8\u4e8e\u6570\u636e\u5b58\u50a8\u548c\u67e5\u8be2\u4f18\u5316\u3002<\/li>\n\n\n\n<li><strong>\u4f18\u5316\u5b58\u50a8\u8fc7\u7a0b<\/strong>\uff1a\u5982\u679c\u5fc5\u987b\u4f7f\u7528\u5b58\u50a8\u8fc7\u7a0b\uff0c\u786e\u4fdd\u5176\u9ad8\u6548\uff0c\u907f\u514d\u590d\u6742\u7684\u5faa\u73af\u3001\u5d4c\u5957\u67e5\u8be2\u7b49\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4f18\u5316\u5b58\u50a8\u8fc7\u7a0b\u7684\u793a\u4f8b\uff0c\u907f\u514d\u590d\u6742\u7684\u5faa\u73af\u548c\u91cd\u590d\u64cd\u4f5c\nCREATE PROCEDURE GetEmployeeDetails\n    @EmployeeID INT\nAS\nBEGIN\n    SELECT Name, Department FROM Employees WHERE EmployeeID = @EmployeeID;\nEND;<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">12. <strong>\u6ca1\u6709\u4f7f\u7528\u4e8b\u52a1\u7ba1\u7406\u5904\u7406\u5931\u8d25\u548c\u56de\u6eda<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u8fdb\u884c\u591a\u6b21\u6570\u636e\u64cd\u4f5c\u65f6\uff0c\u5ffd\u89c6\u4f7f\u7528\u4e8b\u52a1\u53ef\u80fd\u5bfc\u81f4\u6570\u636e\u4e0d\u4e00\u81f4\u3002\u4f8b\u5982\uff0c\u5728\u63d2\u5165\u3001\u66f4\u65b0\u6216\u5220\u9664\u591a\u5f20\u8868\u7684\u6570\u636e\u65f6\uff0c\u5982\u679c\u67d0\u4e00\u6b65\u5931\u8d25\uff0c\u5176\u4ed6\u6b65\u9aa4\u53ef\u80fd\u5df2\u7ecf\u4fee\u6539\u4e86\u6570\u636e\uff0c\u5bfc\u81f4\u6570\u636e\u5e93\u5904\u4e8e\u4e0d\u4e00\u81f4\u7684\u72b6\u6001\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4e8b\u52a1\u7ba1\u7406<\/strong>\uff1a\u5728\u591a\u6b65\u9aa4\u64cd\u4f5c\u4e2d\u4f7f\u7528\u4e8b\u52a1\uff0c\u4ee5\u786e\u4fdd\u64cd\u4f5c\u8981\u4e48\u5168\u90e8\u6210\u529f\uff0c\u8981\u4e48\u5931\u8d25\u65f6\u80fd\u591f\u56de\u6eda\u6240\u6709\u64cd\u4f5c\u3002\u786e\u4fdd\u6570\u636e\u7684\u4e00\u81f4\u6027\u548c\u539f\u5b50\u6027\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u5728 C# \u4e2d\u4f7f\u7528\u4e8b\u52a1\nusing (var transaction = connection.BeginTransaction())\n{\n    try\n    {\n        var command1 = new SqlCommand(\"UPDATE Products SET Price = Price * 1.1 WHERE Category = 'Electronics'\", connection, transaction);\n        command1.ExecuteNonQuery();\n\n        var command2 = new SqlCommand(\"UPDATE Sales SET Total = Total * 1.1 WHERE ProductCategory = 'Electronics'\", connection, transaction);\n        command2.ExecuteNonQuery();\n\n        \/\/ \u63d0\u4ea4\u4e8b\u52a1\n        transaction.Commit();\n    }\n    catch\n    {\n        \/\/ \u5982\u679c\u51fa\u73b0\u4efb\u4f55\u9519\u8bef\uff0c\u5219\u56de\u6eda\u4e8b\u52a1\n        transaction.Rollback();\n    }\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">13. <strong>\u8fc7\u5ea6\u4f7f\u7528 <code>DISTINCT<\/code><\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u67e5\u8be2\u4e2d\u4f7f\u7528 <code>DISTINCT<\/code> \u53ef\u80fd\u4f1a\u5bfc\u81f4\u6027\u80fd\u4e0b\u964d\uff0c\u5c24\u5176\u662f\u5f53\u6ca1\u6709\u5fc5\u8981\u53bb\u91cd\u65f6\u3002<code>DISTINCT<\/code> \u64cd\u4f5c\u9700\u8981\u6392\u5e8f\u6216\u989d\u5916\u7684\u8ba1\u7b97\uff0c\u8fd9\u4f1a\u589e\u52a0\u67e5\u8be2\u7684\u5f00\u9500\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u53bb\u9664\u4e0d\u5fc5\u8981\u7684 <code>DISTINCT<\/code><\/strong>\uff1a\u4ec5\u5728\u660e\u786e\u9700\u8981\u53bb\u9664\u91cd\u590d\u6570\u636e\u65f6\u624d\u4f7f\u7528 <code>DISTINCT<\/code>\u3002\u5982\u679c\u6570\u636e\u5e93\u8868\u5df2\u7ecf\u4fdd\u8bc1\u6570\u636e\u552f\u4e00\u6027\u6216\u67e5\u8be2\u6761\u4ef6\u9650\u5236\u4e86\u6570\u636e\u96c6\uff0c<code>DISTINCT<\/code> \u662f\u4e0d\u5fc5\u8981\u7684\u3002<\/li>\n\n\n\n<li><strong>\u8c03\u6574\u6570\u636e\u6a21\u578b<\/strong>\uff1a\u5982\u679c\u67e5\u8be2\u4e2d\u9891\u7e41\u9700\u8981 <code>DISTINCT<\/code>\uff0c\u53ef\u80fd\u9700\u8981\u91cd\u65b0\u8bbe\u8ba1\u6570\u636e\u6a21\u578b\uff0c\u907f\u514d\u5197\u4f59\u6570\u636e\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4e0d\u63a8\u8350\uff1a\u4e0d\u5fc5\u8981\u7684 DISTINCT\nSELECT DISTINCT Name, Department FROM Employees;\n\n-- \u63a8\u8350\uff1a\u53ea\u5728\u9700\u8981\u65f6\u4f7f\u7528 DISTINCT\nSELECT Name, Department FROM Employees WHERE Department = 'Sales';<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">14. <strong>\u6ee5\u7528\u89e6\u53d1\u5668<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u89e6\u53d1\u5668\uff08Triggers\uff09\u53ef\u4ee5\u5728\u6570\u636e\u66f4\u6539\u65f6\u81ea\u52a8\u6267\u884c\uff0c\u4f46\u5982\u679c\u6ee5\u7528\u89e6\u53d1\u5668\uff0c\u4f1a\u5bfc\u81f4\u590d\u6742\u7684\u4f9d\u8d56\u5173\u7cfb\u3001\u6027\u80fd\u95ee\u9898\u4ee5\u53ca\u96be\u4ee5\u8c03\u8bd5\u7684\u60c5\u51b5\u3002\u7279\u522b\u662f\u5f53\u89e6\u53d1\u5668\u6267\u884c\u5176\u4ed6\u67e5\u8be2\u65f6\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u989d\u5916\u7684\u6570\u636e\u5e93\u8d1f\u62c5\uff0c\u5f71\u54cd\u7cfb\u7edf\u7684\u6027\u80fd\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u907f\u514d\u8fc7\u591a\u7684\u89e6\u53d1\u5668<\/strong>\uff1a\u4ec5\u5728\u786e\u5b9e\u9700\u8981\u65f6\u4f7f\u7528\u89e6\u53d1\u5668\uff0c\u907f\u514d\u5728\u8868\u4e0a\u521b\u5efa\u8fc7\u591a\u7684\u89e6\u53d1\u5668\u3002\u4f7f\u7528\u89e6\u53d1\u5668\u65f6\uff0c\u786e\u4fdd\u5b83\u4eec\u662f\u9ad8\u6548\u7684\uff0c\u5e76\u4e14\u6ca1\u6709\u5bfc\u81f4\u4e0d\u5fc5\u8981\u7684\u9012\u5f52\u6216\u8054\u52a8\u3002<\/li>\n\n\n\n<li><strong>\u4f7f\u7528\u5e94\u7528\u7a0b\u5e8f\u903b\u8f91\u4ee3\u66ff\u89e6\u53d1\u5668<\/strong>\uff1a\u5728\u4e00\u4e9b\u573a\u666f\u4e0b\uff0c\u4e1a\u52a1\u903b\u8f91\u53ef\u4ee5\u653e\u5728\u5e94\u7528\u7a0b\u5e8f\u5c42\uff0c\u800c\u4e0d\u662f\u6570\u636e\u5e93\u5c42\u3002\u8fd9\u6837\u53ef\u4ee5\u63d0\u9ad8\u53ef\u7ef4\u62a4\u6027\u548c\u7075\u6d3b\u6027\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4e0d\u63a8\u8350\uff1a\u5728\u6bcf\u6b21\u63d2\u5165\u6570\u636e\u65f6\u6267\u884c\u590d\u6742\u64cd\u4f5c\u7684\u89e6\u53d1\u5668\nCREATE TRIGGER trg_AfterInsert \nON Orders\nFOR INSERT\nAS\nBEGIN\n    -- \u8fdb\u884c\u590d\u6742\u7684\u8ba1\u7b97\u6216\u6570\u636e\u63d2\u5165\nEND;\n\n-- \u63a8\u8350\uff1a\u5c06\u4e1a\u52a1\u903b\u8f91\u79fb\u81f3\u5e94\u7528\u5c42\u5904\u7406<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">15. <strong>\u6ca1\u6709\u9002\u5f53\u7684\u6570\u636e\u6e05\u7406\u7b56\u7565<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u957f\u671f\u79ef\u7d2f\u7684\u6570\u636e\u5982\u679c\u6ca1\u6709\u5b9a\u671f\u6e05\u7406\uff0c\u53ef\u80fd\u5bfc\u81f4\u6570\u636e\u5e93\u81a8\u80c0\uff0c\u5f71\u54cd\u67e5\u8be2\u6027\u80fd\u3002\u5c24\u5176\u662f\u5f53\u67d0\u4e9b\u8868\u4e0d\u518d\u4f7f\u7528\u65f6\uff0c\u5b83\u4eec\u4ecd\u7136\u5360\u636e\u6570\u636e\u5e93\u7684\u7a7a\u95f4\uff0c\u589e\u52a0\u4e86\u5b58\u50a8\u6210\u672c\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5b9a\u671f\u6e05\u7406\u5386\u53f2\u6570\u636e<\/strong>\uff1a\u5236\u5b9a\u6570\u636e\u6e05\u7406\u7b56\u7565\uff0c\u5bf9\u4e8e\u4e0d\u518d\u4f7f\u7528\u7684\u6570\u636e\uff0c\u5b9a\u671f\u5c06\u5176\u5220\u9664\u6216\u5f52\u6863\u5230\u5176\u4ed6\u5730\u65b9\u3002<\/li>\n\n\n\n<li><strong>\u5206\u533a\u8868<\/strong>\uff1a\u5bf9\u4e8e\u975e\u5e38\u5927\u7684\u8868\uff0c\u4f7f\u7528\u5206\u533a\u7b56\u7565\uff0c\u5c06\u6570\u636e\u5206\u5272\u4e3a\u591a\u4e2a\u903b\u8f91\u90e8\u5206\uff0c\u63d0\u9ad8\u67e5\u8be2\u6027\u80fd\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4f7f\u7528\u5206\u533a\u6765\u7ba1\u7406\u5927\u6570\u636e\u8868\nCREATE PARTITION FUNCTION MyPartitionFunction (int)\nAS RANGE LEFT FOR VALUES (1000, 2000, 3000);\n\nCREATE PARTITION SCHEME MyPartitionScheme\nAS PARTITION MyPartitionFunction\nTO (fg1, fg2, fg3);<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">16. <strong>\u5ffd\u7565 SQL Server \u7684\u5e76\u53d1\u63a7\u5236\u673a\u5236<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u4e0d\u5904\u7406\u5e76\u53d1\u95ee\u9898\uff0c\u53ef\u80fd\u5bfc\u81f4\u6570\u636e\u7684\u4e0d\u4e00\u81f4\u6027\u548c\u7ade\u4e89\u6761\u4ef6\u3002\u4f8b\u5982\uff0c\u5f53\u591a\u4e2a\u7528\u6237\u540c\u65f6\u66f4\u65b0\u76f8\u540c\u7684\u6570\u636e\u65f6\uff0c\u53ef\u80fd\u5bfc\u81f4\u6570\u636e\u4e22\u5931\u6216\u51b2\u7a81\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4f7f\u7528\u4e50\u89c2\u9501\u5b9a\u548c\u60b2\u89c2\u9501\u5b9a<\/strong>\uff1a\u4f7f\u7528\u5408\u9002\u7684\u5e76\u53d1\u63a7\u5236\u7b56\u7565\uff0c\u786e\u4fdd\u5728\u5e76\u53d1\u60c5\u51b5\u4e0b\u6570\u636e\u7684\u4e00\u81f4\u6027\u3002<\/li>\n\n\n\n<li><strong>\u4e50\u89c2\u9501\u5b9a<\/strong>\uff1a\u9002\u7528\u4e8e\u8bfb\u591a\u5199\u5c11\u7684\u573a\u666f\uff0c\u901a\u5e38\u901a\u8fc7\u7248\u672c\u53f7\u6216\u65f6\u95f4\u6233\u6765\u5b9e\u73b0\u3002<\/li>\n\n\n\n<li><strong>\u60b2\u89c2\u9501\u5b9a<\/strong>\uff1a\u9002\u7528\u4e8e\u5199\u591a\u7684\u573a\u666f\uff0c\u4f7f\u7528\u9501\u6765\u786e\u4fdd\u5728\u5904\u7406\u6570\u636e\u65f6\u5176\u4ed6\u64cd\u4f5c\u65e0\u6cd5\u4fee\u6539\u76f8\u540c\u7684\u6570\u636e\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4e50\u89c2\u9501\u5b9a\u793a\u4f8b\uff1a\u4f7f\u7528\u7248\u672c\u53f7\nUPDATE Employees\nSET Salary = 5000\nWHERE EmployeeID = @EmployeeID AND Version = @Version;\n\n-- \u60b2\u89c2\u9501\u5b9a\u793a\u4f8b\uff1a\u5728 SELECT \u67e5\u8be2\u65f6\u4f7f\u7528\u9501\nSELECT * \nFROM Employees WITH (ROWLOCK)\nWHERE EmployeeID = @EmployeeID;<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">17. <strong>\u4f4e\u6548\u7684\u66f4\u65b0\u64cd\u4f5c<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u95ee\u9898\uff1a<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u66f4\u65b0\u5927\u91cf\u8bb0\u5f55\u65f6\uff0c\u5982\u679c\u6ca1\u6709\u9002\u5f53\u7684\u6761\u4ef6\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u5168\u8868\u66f4\u65b0\uff0c\u6781\u5927\u5730\u5f71\u54cd\u6027\u80fd\u3002\u5c24\u5176\u662f\u5728\u6570\u636e\u91cf\u5927\u7684\u60c5\u51b5\u4e0b\uff0c\u6267\u884c\u66f4\u65b0\u65f6\u8981\u5c0f\u5fc3\u907f\u514d\u65e0\u8c13\u7684\u66f4\u65b0\u64cd\u4f5c\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u89e3\u51b3\u65b9\u6848\uff1a<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7cbe\u786e\u7684\u6761\u4ef6\u66f4\u65b0<\/strong>\uff1a\u786e\u4fdd\u5728 <code>UPDATE<\/code> \u8bed\u53e5\u4e2d\u4f7f\u7528\u9002\u5f53\u7684\u6761\u4ef6\uff0c\u4ee5\u4ec5\u66f4\u65b0\u9700\u8981\u66f4\u65b0\u7684\u8bb0\u5f55\u3002<\/li>\n\n\n\n<li><strong>\u6279\u91cf\u66f4\u65b0<\/strong>\uff1a\u5bf9\u4e8e\u5927\u91cf\u66f4\u65b0\uff0c\u8003\u8651\u5206\u6279\u5904\u7406\uff0c\u6bcf\u6b21\u66f4\u65b0\u5c11\u91cf\u8bb0\u5f55\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>-- \u4e0d\u63a8\u8350\uff1a\u5168\u8868\u66f4\u65b0\nUPDATE Employees SET Salary = 5000;\n\n-- \u63a8\u8350\uff1a\u7cbe\u786e\u66f4\u65b0\nUPDATE Employees SET Salary = 5000 WHERE Department = 'Sales';<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">\u603b\u7ed3<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u907f\u514d SQL \u53cd\u6a21\u5f0f\u80fd\u591f\u663e\u8457\u63d0\u5347\u7cfb\u7edf\u7684\u6027\u80fd\u3001\u53ef\u7ef4\u62a4\u6027\u548c\u5b89\u5168\u6027\u3002\u4ee5\u4e0b\u662f\u4e00\u4e9b\u91cd\u8981\u7684\u6700\u4f73\u5b9e\u8df5\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4f18\u5316\u67e5\u8be2<\/strong>\uff0c\u907f\u514d\u4e0d\u5fc5\u8981\u7684 <code>JOIN<\/code>\u3001<code>DISTINCT<\/code> \u548c\u5b50\u67e5\u8be2\u3002<\/li>\n\n\n\n<li><strong>\u4f7f\u7528\u4e8b\u52a1<\/strong> \u786e\u4fdd\u6570\u636e\u4e00\u81f4\u6027\u3002<\/li>\n\n\n\n<li><strong>\u907f\u514d\u786c\u7f16\u7801 SQL<\/strong>\uff0c\u4f7f\u7528\u53c2\u6570\u5316\u67e5\u8be2\u3002<\/li>\n\n\n\n<li><strong>\u8003\u8651\u5e76\u53d1\u63a7\u5236<\/strong>\uff0c\u907f\u514d\u7ade\u4e89\u6761\u4ef6\u3002<\/li>\n\n\n\n<li><strong>\u5b9a\u671f\u6e05\u7406\u6570\u636e<\/strong>\uff0c\u907f\u514d\u6570\u636e\u5e93\u81a8\u80c0\u3002<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u8fc7\u8fd9\u4e9b\u63aa\u65bd\uff0c\u4f60\u53ef\u4ee5\u786e\u4fdd\u6570\u636e\u5e93\u67e5\u8be2\u548c\u64cd\u4f5c\u4e0d\u4ec5\u9ad8\u6548\uff0c\u8fd8\u80fd\u4fdd\u6301\u6570\u636e\u7684\u5b8c\u6574\u6027\u548c\u5b89\u5168\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5728\u6570\u636e\u8bbf\u95ee\u5c42\u4e2d\uff0c\u907f\u514d\u5e38\u89c1\u7684 SQL \u53cd\u6a21\u5f0f\u5bf9\u4e8e\u63d0\u9ad8\u5e94\u7528\u7a0b\u5e8f\u7684\u6027\u80fd\u3001\u5b89\u5168\u6027\u3001\u53ef\u7ef4\u62a4\u6027\u548c\u53ef\u6269\u5c55\u6027\u81f3\u5173\u91cd\u8981\u3002SQL  [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[],"class_list":["post-806","post","type-post","status-publish","format-standard","hentry","category-mysql"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/806","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=806"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/806\/revisions"}],"predecessor-version":[{"id":807,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/806\/revisions\/807"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=806"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=806"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=806"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}