{"id":196195,"date":"2024-11-13T21:16:24","date_gmt":"2024-11-13T13:16:24","guid":{"rendered":"https:\/\/server.hk\/cnblog\/196195\/"},"modified":"2024-11-13T21:16:25","modified_gmt":"2024-11-13T13:16:25","slug":"%e6%8e%8c%e6%8f%a1%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8%e9%80%a3%e6%8e%a5%e7%9a%84%e8%aa%9e%e5%8f%a5%ef%bc%8c%e8%bc%95%e9%ac%86%e5%af%a6%e7%8f%be%e6%95%b8%e6%93%9a%e6%9f%a5%e8%a9%a2%e3%80%81%e5%88%86","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/196195\/","title":{"rendered":"\u638c\u63e1\u6578\u64da\u5eab\u8868\u9023\u63a5\u7684\u8a9e\u53e5\uff0c\u8f15\u9b06\u5be6\u73fe\u6578\u64da\u67e5\u8a62\u3001\u5206\u6790\u8207\u8655\u7406 (\u6578\u64da\u5eab\u5169\u5f35\u8868\u9023\u63a5\u7684\u8a9e\u53e5)"},"content":{"rendered":"<h1 id=\"%e6%8e%8c%e6%8f%a1%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8%e9%80%a3%e6%8e%a5%e7%9a%84%e8%aa%9e%e5%8f%a5%ef%bc%8c%e8%bc%95%e9%ac%86%e5%af%a6%e7%8f%be%e6%95%b8%e6%93%9a%e6%9f%a5%e8%a9%a2%e3%80%81%e5%88%86-UvnPuCvExL\">\u638c\u63e1\u6578\u64da\u5eab\u8868\u9023\u63a5\u7684\u8a9e\u53e5\uff0c\u8f15\u9b06\u5be6\u73fe\u6578\u64da\u67e5\u8a62\u3001\u5206\u6790\u8207\u8655\u7406<\/h1>\n<p>\u5728\u73fe\u4ee3\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u6578\u64da\u7684\u67e5\u8a62\u3001\u5206\u6790\u8207\u8655\u7406\u662f\u81f3\u95dc\u91cd\u8981\u7684\uff0c\u800c\u8868\u4e4b\u9593\u7684\u9023\u63a5\u5247\u662f\u5be6\u73fe\u9019\u4e9b\u64cd\u4f5c\u7684\u95dc\u9375\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528 SQL \u8a9e\u53e5\u4f86\u9023\u63a5\u5169\u5f35\u8868\uff0c\u4e26\u63d0\u4f9b\u5be6\u7528\u7684\u7bc4\u4f8b\u548c\u4ee3\u78bc\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u597d\u5730\u7406\u89e3\u9019\u4e00\u904e\u7a0b\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8%e9%80%a3%e6%8e%a5%ef%bc%9f-UvnPuCvExL\">\u4ec0\u9ebc\u662f\u6578\u64da\u5eab\u8868\u9023\u63a5\uff1f<\/h2>\n<p>\u6578\u64da\u5eab\u8868\u9023\u63a5\u662f\u6307\u5728\u67e5\u8a62\u4e2d\u5c07\u5169\u5f35\u6216\u591a\u5f35\u8868\u7684\u6578\u64da\u6839\u64da\u67d0\u4e9b\u689d\u4ef6\u9032\u884c\u7d44\u5408\u7684\u904e\u7a0b\u3002\u9019\u7a2e\u64cd\u4f5c\u901a\u5e38\u7528\u65bc\u7372\u53d6\u66f4\u5168\u9762\u7684\u6578\u64da\u8996\u5716\uff0c\u5f9e\u800c\u652f\u6301\u66f4\u8907\u96dc\u7684\u67e5\u8a62\u548c\u5206\u6790\u3002\u5e38\u898b\u7684\u9023\u63a5\u985e\u578b\u5305\u62ec\u5167\u9023\u63a5\uff08INNER JOIN\uff09\u3001\u5916\u9023\u63a5\uff08OUTER JOIN\uff09\u3001\u4ea4\u53c9\u9023\u63a5\uff08CROSS JOIN\uff09\u7b49\u3002<\/p>\n<h2 id=\"%e5%85%a7%e9%80%a3%e6%8e%a5%ef%bc%88inner-join%ef%bc%89-UvnPuCvExL\">\u5167\u9023\u63a5\uff08INNER JOIN\uff09<\/h2>\n<p>\u5167\u9023\u63a5\u662f\u6700\u5e38\u7528\u7684\u9023\u63a5\u985e\u578b\uff0c\u5b83\u53ea\u8fd4\u56de\u5169\u5f35\u8868\u4e2d\u5339\u914d\u7684\u884c\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>SELECT a.name, b.order_date\nFROM customers a\nINNER JOIN orders b ON a.customer_id = b.customer_id;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u5f9e <code>customers<\/code> \u8868\u548c <code>orders<\/code> \u8868\u4e2d\u9078\u53d6\u5ba2\u6236\u540d\u7a31\u548c\u8a02\u55ae\u65e5\u671f\uff0c\u4e26\u901a\u904e <code>customer_id<\/code> \u9032\u884c\u9023\u63a5\u3002\u53ea\u6709\u90a3\u4e9b\u5728\u5169\u5f35\u8868\u4e2d\u90fd\u6709\u7684\u5ba2\u6236\u548c\u8a02\u55ae\u624d\u6703\u88ab\u8fd4\u56de\u3002<\/p>\n<h2 id=\"%e5%a4%96%e9%80%a3%e6%8e%a5%ef%bc%88outer-join%ef%bc%89-UvnPuCvExL\">\u5916\u9023\u63a5\uff08OUTER JOIN\uff09<\/h2>\n<p>\u5916\u9023\u63a5\u5247\u6703\u8fd4\u56de\u81f3\u5c11\u4e00\u5f35\u8868\u4e2d\u7684\u6240\u6709\u884c\uff0c\u5373\u4f7f\u5728\u53e6\u4e00\u5f35\u8868\u4e2d\u6c92\u6709\u5339\u914d\u7684\u884c\u3002\u5916\u9023\u63a5\u53c8\u5206\u70ba\u5de6\u5916\u9023\u63a5\uff08LEFT JOIN\uff09\u548c\u53f3\u5916\u9023\u63a5\uff08RIGHT JOIN\uff09\u3002\u4ee5\u4e0b\u662f\u5de6\u5916\u9023\u63a5\u7684\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>SELECT a.name, b.order_date\nFROM customers a\nLEFT JOIN orders b ON a.customer_id = b.customer_id;<\/code><\/pre>\n<p>\u9019\u6bb5\u4ee3\u78bc\u5c07\u8fd4\u56de\u6240\u6709\u5ba2\u6236\u7684\u540d\u7a31\uff0c\u5373\u4f7f\u67d0\u4e9b\u5ba2\u6236\u6c92\u6709\u8a02\u55ae\u3002\u5728\u9019\u7a2e\u60c5\u6cc1\u4e0b\uff0c<code>order_date<\/code> \u5c07\u986f\u793a\u70ba <code>NULL<\/code>\u3002<\/p>\n<h2 id=\"%e4%ba%a4%e5%8f%89%e9%80%a3%e6%8e%a5%ef%bc%88cross-join%ef%bc%89-UvnPuCvExL\">\u4ea4\u53c9\u9023\u63a5\uff08CROSS JOIN\uff09<\/h2>\n<p>\u4ea4\u53c9\u9023\u63a5\u6703\u8fd4\u56de\u5169\u5f35\u8868\u7684\u7b1b\u5361\u723e\u7a4d\uff0c\u5373\u6bcf\u4e00\u884c\u90fd\u6703\u8207\u53e6\u4e00\u5f35\u8868\u7684\u6bcf\u4e00\u884c\u9032\u884c\u7d44\u5408\u3002\u9019\u7a2e\u9023\u63a5\u901a\u5e38\u4e0d\u5e38\u7528\uff0c\u4f46\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\u53ef\u80fd\u6703\u6709\u7528\u3002\u4ee5\u4e0b\u662f\u4ea4\u53c9\u9023\u63a5\u7684\u7bc4\u4f8b\uff1a<\/p>\n<pre><code>SELECT a.name, b.product_name\nFROM customers a\nCROSS JOIN products b;<\/code><\/pre>\n<p>\u9019\u6bb5\u4ee3\u78bc\u5c07\u8fd4\u56de\u6240\u6709\u5ba2\u6236\u8207\u6240\u6709\u7522\u54c1\u7684\u7d44\u5408\uff0c\u751f\u6210\u4e00\u500b\u5305\u542b\u6240\u6709\u53ef\u80fd\u914d\u5c0d\u7684\u7d50\u679c\u96c6\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8%e9%80%a3%e6%8e%a5%e7%9a%84%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-UvnPuCvExL\">\u4f7f\u7528\u9023\u63a5\u7684\u6ce8\u610f\u4e8b\u9805<\/h2>\n<ul>\n<li><strong>\u6027\u80fd\u8003\u91cf\uff1a<\/strong>\u5728\u8655\u7406\u5927\u578b\u6578\u64da\u96c6\u6642\uff0c\u9023\u63a5\u64cd\u4f5c\u53ef\u80fd\u6703\u5f71\u97ff\u67e5\u8a62\u6027\u80fd\uff0c\u56e0\u6b64\u61c9\u8b39\u614e\u4f7f\u7528\u3002<\/li>\n<li><strong>\u7d22\u5f15\uff1a<\/strong>\u70ba\u9023\u63a5\u7684\u5217\u5efa\u7acb\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\u3002<\/li>\n<li><strong>\u6578\u64da\u5b8c\u6574\u6027\uff1a<\/strong>\u78ba\u4fdd\u9023\u63a5\u7684\u5217\u5177\u6709\u6b63\u78ba\u7684\u6578\u64da\u985e\u578b\u548c\u7d04\u675f\uff0c\u4ee5\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u932f\u8aa4\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-UvnPuCvExL\">\u7e3d\u7d50<\/h2>\n<p>\u638c\u63e1\u6578\u64da\u5eab\u8868\u9023\u63a5\u7684\u8a9e\u53e5\u5c0d\u65bc\u6578\u64da\u67e5\u8a62\u3001\u5206\u6790\u8207\u8655\u7406\u81f3\u95dc\u91cd\u8981\u3002\u901a\u904e\u5167\u9023\u63a5\u3001\u5916\u9023\u63a5\u548c\u4ea4\u53c9\u9023\u63a5\u7b49\u4e0d\u540c\u7684\u9023\u63a5\u65b9\u5f0f\uff0c\u60a8\u53ef\u4ee5\u9748\u6d3b\u5730\u7372\u53d6\u6240\u9700\u7684\u6578\u64da\u3002\u7121\u8ad6\u662f\u5728\u958b\u767c\u61c9\u7528\u7a0b\u5e8f\u9084\u662f\u9032\u884c\u6578\u64da\u5206\u6790\uff0c\u9019\u4e9b\u6280\u80fd\u90fd\u5c07\u5e6b\u52a9\u60a8\u66f4\u6709\u6548\u5730\u7ba1\u7406\u548c\u5229\u7528\u6578\u64da\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4f86\u652f\u6301\u60a8\u7684\u6578\u64da\u5eab\u64cd\u4f5c\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\">\u9999\u6e2fVPS<\/a> 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