{"id":168395,"date":"2024-11-06T12:01:26","date_gmt":"2024-11-06T04:01:26","guid":{"rendered":"https:\/\/server.hk\/cnblog\/168395\/"},"modified":"2024-11-06T12:01:27","modified_gmt":"2024-11-06T04:01:27","slug":"sql-%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f%e5%b0%8e%e8%87%b4%e7%84%a1%e6%b3%95%e6%b7%bb%e5%8a%a0%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8-%e5%a6%82%e4%bd%95%e8%a7%a3%e6%b1%ba%ef%bc%9f-sql","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/168395\/","title":{"rendered":"SQL \u5916\u9375\u7d04\u675f\u5c0e\u81f4\u7121\u6cd5\u6dfb\u52a0\u6578\u64da\u5eab\u8868 \u2013 \u5982\u4f55\u89e3\u6c7a\uff1f (sql \u8a2d\u7f6e\u5916\u9375\u5f8c\u6dfb\u52a0\u4e0d\u4e86\u6578\u64da\u5eab)"},"content":{"rendered":"<h1 id=\"sql-%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f%e5%b0%8e%e8%87%b4%e7%84%a1%e6%b3%95%e6%b7%bb%e5%8a%a0%e6%95%b8%e6%93%9a%e5%ba%ab%e8%a1%a8-%e5%a6%82%e4%bd%95%e8%a7%a3%e6%b1%ba%ef%bc%9f-ypGYDVHwuk\">SQL \u5916\u9375\u7d04\u675f\u5c0e\u81f4\u7121\u6cd5\u6dfb\u52a0\u6578\u64da\u5eab\u8868 \u2013 \u5982\u4f55\u89e3\u6c7a\uff1f<\/h1>\n<p>\u5728\u4f7f\u7528 SQL \u6578\u64da\u5eab\u6642\uff0c\u5916\u9375\u7d04\u675f\u662f\u4e00\u500b\u91cd\u8981\u7684\u529f\u80fd\uff0c\u5b83\u80fd\u5920\u78ba\u4fdd\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u4e00\u81f4\u6027\u3002\u7136\u800c\uff0c\u7576\u6211\u5011\u5728\u8a2d\u7f6e\u5916\u9375\u7d04\u675f\u5f8c\uff0c\u53ef\u80fd\u6703\u9047\u5230\u7121\u6cd5\u6dfb\u52a0\u6578\u64da\u7684\u60c5\u6cc1\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5916\u9375\u7d04\u675f\u7684\u5de5\u4f5c\u539f\u7406\uff0c\u5e38\u898b\u7684\u554f\u984c\u53ca\u5176\u89e3\u6c7a\u65b9\u6848\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f%ef%bc%9f-ypGYDVHwuk\">\u4ec0\u9ebc\u662f\u5916\u9375\u7d04\u675f\uff1f<\/h2>\n<p>\u5916\u9375\u7d04\u675f\u662f\u4e00\u7a2e\u6578\u64da\u5eab\u7d04\u675f\uff0c\u7528\u65bc\u5efa\u7acb\u548c\u5f37\u5316\u5169\u500b\u8868\u4e4b\u9593\u7684\u95dc\u806f\u3002\u7576\u4e00\u500b\u8868\u4e2d\u7684\u67d0\u500b\u5b57\u6bb5\uff08\u5916\u9375\uff09\u5f15\u7528\u53e6\u4e00\u500b\u8868\u4e2d\u7684\u4e3b\u9375\u6642\uff0c\u5c31\u6703\u5f62\u6210\u5916\u9375\u7d04\u675f\u3002\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u5728\u5916\u9375\u8868\u4e2d\u63d2\u5165\u7684\u6578\u64da\u5fc5\u9808\u5728\u4e3b\u9375\u8868\u4e2d\u5b58\u5728\uff0c\u5f9e\u800c\u7dad\u8b77\u6578\u64da\u7684\u5b8c\u6574\u6027\u3002<\/p>\n<h2 id=\"%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f%e5%b0%8e%e8%87%b4%e7%84%a1%e6%b3%95%e6%b7%bb%e5%8a%a0%e6%95%b8%e6%93%9a%e7%9a%84%e5%8e%9f%e5%9b%a0-ypGYDVHwuk\">\u5916\u9375\u7d04\u675f\u5c0e\u81f4\u7121\u6cd5\u6dfb\u52a0\u6578\u64da\u7684\u539f\u56e0<\/h2>\n<p>\u7576\u4f60\u5617\u8a66\u5728\u8a2d\u7f6e\u4e86\u5916\u9375\u7d04\u675f\u7684\u8868\u4e2d\u6dfb\u52a0\u6578\u64da\u6642\uff0c\u53ef\u80fd\u6703\u9047\u5230\u4ee5\u4e0b\u5e7e\u7a2e\u60c5\u6cc1\uff1a<\/p>\n<ul>\n<li><strong>\u53c3\u8003\u7684\u4e3b\u9375\u4e0d\u5b58\u5728\uff1a<\/strong>\u5982\u679c\u4f60\u5617\u8a66\u63d2\u5165\u7684\u5916\u9375\u503c\u5728\u4e3b\u9375\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c\u6578\u64da\u5eab\u5c07\u62d2\u7d55\u9019\u500b\u64cd\u4f5c\u3002<\/li>\n<li><strong>\u6578\u64da\u985e\u578b\u4e0d\u5339\u914d\uff1a<\/strong>\u5916\u9375\u548c\u4e3b\u9375\u7684\u6578\u64da\u985e\u578b\u5fc5\u9808\u4e00\u81f4\u3002\u5982\u679c\u4e0d\u4e00\u81f4\uff0c\u5c07\u7121\u6cd5\u6210\u529f\u63d2\u5165\u6578\u64da\u3002<\/li>\n<li><strong>\u9055\u53cd\u552f\u4e00\u6027\u7d04\u675f\uff1a<\/strong>\u5982\u679c\u5916\u9375\u8868\u4e2d\u5df2\u7d93\u5b58\u5728\u76f8\u540c\u7684\u5916\u9375\u503c\uff0c\u5247\u7121\u6cd5\u518d\u6b21\u63d2\u5165\u76f8\u540c\u7684\u503c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%a6%82%e4%bd%95%e8%a7%a3%e6%b1%ba%e5%a4%96%e9%8d%b5%e7%b4%84%e6%9d%9f%e5%b0%8e%e8%87%b4%e7%9a%84%e5%95%8f%e9%a1%8c-ypGYDVHwuk\">\u5982\u4f55\u89e3\u6c7a\u5916\u9375\u7d04\u675f\u5c0e\u81f4\u7684\u554f\u984c<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e9b\u89e3\u6c7a\u5916\u9375\u7d04\u675f\u554f\u984c\u7684\u5e38\u898b\u65b9\u6cd5\uff1a<\/p>\n<h3 id=\"1-%e7%a2%ba%e4%bf%9d%e4%b8%bb%e9%8d%b5%e5%ad%98%e5%9c%a8-ypGYDVHwuk\">1. \u78ba\u4fdd\u4e3b\u9375\u5b58\u5728<\/h3>\n<p>\u5728\u63d2\u5165\u5916\u9375\u6578\u64da\u4e4b\u524d\uff0c\u9996\u5148\u8981\u78ba\u4fdd\u4e3b\u9375\u8868\u4e2d\u5df2\u7d93\u5b58\u5728\u76f8\u61c9\u7684\u4e3b\u9375\u503c\u3002\u4f8b\u5982\uff0c\u5047\u8a2d\u6709\u5169\u500b\u8868\uff1a<code>users<\/code> \u548c <code>orders<\/code>\uff0c\u5176\u4e2d <code>orders<\/code> \u8868\u7684 <code>user_id<\/code> \u662f\u5916\u9375\uff0c\u5f15\u7528 <code>users<\/code> \u8868\u7684 <code>id<\/code>\u3002\u5728\u63d2\u5165\u4e00\u689d\u8a02\u55ae\u4e4b\u524d\uff0c\u5fc5\u9808\u78ba\u4fdd\u8a72\u7528\u6236\u5df2\u7d93\u5b58\u5728\u65bc <code>users<\/code> \u8868\u4e2d\u3002<\/p>\n<pre><code>INSERT INTO users (id, name) VALUES (1, 'Alice');\nINSERT INTO orders (order_id, user_id) VALUES (101, 1);<\/code><\/pre>\n<h3 id=\"2-%e6%aa%a2%e6%9f%a5%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b-ypGYDVHwuk\">2. \u6aa2\u67e5\u6578\u64da\u985e\u578b<\/h3>\n<p>\u78ba\u4fdd\u5916\u9375\u548c\u4e3b\u9375\u7684\u6578\u64da\u985e\u578b\u4e00\u81f4\u3002\u4f8b\u5982\uff0c\u5982\u679c <code>users.id<\/code> \u662f\u6574\u6578\u985e\u578b\uff0c\u90a3\u9ebc <code>orders.user_id<\/code> \u4e5f\u5fc5\u9808\u662f\u6574\u6578\u985e\u578b\u3002\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u67e5\u8a62\u4f86\u6aa2\u67e5\u8868\u7d50\u69cb\uff1a<\/p>\n<pre><code>DESCRIBE users;\nDESCRIBE orders;<\/code><\/pre>\n<h3 id=\"3-%e8%99%95%e7%90%86%e5%94%af%e4%b8%80%e6%80%a7%e7%b4%84%e6%9d%9f-ypGYDVHwuk\">3. \u8655\u7406\u552f\u4e00\u6027\u7d04\u675f<\/h3>\n<p>\u5982\u679c\u5916\u9375\u8868\u4e2d\u5df2\u7d93\u5b58\u5728\u76f8\u540c\u7684\u5916\u9375\u503c\uff0c\u5247\u9700\u8981\u8003\u616e\u662f\u5426\u9700\u8981\u66f4\u65b0\u73fe\u6709\u8a18\u9304\u6216\u522a\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u67e5\u8a62\u4f86\u6aa2\u67e5\u91cd\u8907\u7684\u5916\u9375\u503c\uff1a<\/p>\n<pre><code>SELECT user_id, COUNT(*) \nFROM orders \nGROUP BY user_id \nHAVING COUNT(*) &gt; 1;<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-ypGYDVHwuk\">\u7e3d\u7d50<\/h2>\n<p>\u5916\u9375\u7d04\u675f\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u4e2d\u626e\u6f14\u8457\u91cd\u8981\u89d2\u8272\uff0c\u80fd\u5920\u5e6b\u52a9\u7dad\u8b77\u6578\u64da\u7684\u5b8c\u6574\u6027\u3002\u7136\u800c\uff0c\u7576\u9047\u5230\u7121\u6cd5\u6dfb\u52a0\u6578\u64da\u7684\u60c5\u6cc1\u6642\uff0c\u4e86\u89e3\u5916\u9375\u7d04\u675f\u7684\u5de5\u4f5c\u539f\u7406\u53ca\u5176\u5e38\u898b\u554f\u984c\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u901a\u904e\u78ba\u4fdd\u4e3b\u9375\u5b58\u5728\u3001\u6aa2\u67e5\u6578\u64da\u985e\u578b\u548c\u8655\u7406\u552f\u4e00\u6027\u7d04\u675f\uff0c\u53ef\u4ee5\u6709\u6548\u89e3\u6c7a\u9019\u4e9b\u554f\u984c\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\u60a8\u7684\u9700\u6c42\u3002\u7121\u8ad6\u662f\u6578\u64da\u5eab\u7ba1\u7406\u9084\u662f\u5176\u4ed6\u61c9\u7528\uff0c\u9078\u64c7\u5408\u9069\u7684 <a href=\"https:\/\/server.hk\">\u4f3a\u670d\u5668<\/a> \u5c07\u6709\u52a9\u65bc\u63d0\u5347\u60a8\u7684\u696d\u52d9\u6548\u7387\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u89e3\u6c7a SQL \u5916\u9375\u7d04\u675f\u5c0e\u81f4\u7121\u6cd5\u6dfb\u52a0\u6578\u64da\u5eab\u8868\u7684\u554f\u984c\uff0c\u78ba\u4fdd\u6578\u64da\u5b8c\u6574\u6027\u8207\u6b63\u78ba\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-168395","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/168395","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=168395"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/168395\/revisions"}],"predecessor-version":[{"id":168396,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/168395\/revisions\/168396"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=168395"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=168395"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=168395"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}