{"id":158191,"date":"2024-11-03T00:46:22","date_gmt":"2024-11-02T16:46:22","guid":{"rendered":"https:\/\/server.hk\/cnblog\/158191\/"},"modified":"2024-11-03T00:46:23","modified_gmt":"2024-11-02T16:46:23","slug":"%e9%ab%98%e6%95%88%e5%af%a6%e7%8f%be%e6%95%b8%e6%93%9a%e5%a4%9a%e6%a2%9d%e4%bb%b6%e7%b5%b1%e8%a8%88%e4%b8%8d%e9%87%8d%e8%a4%87%ef%bc%88%e5%a4%9a%e6%a2%9d%e4%bb%b6%e7%b5%b1%e8%a8%88%e4%b8%8d%e9%87%8d","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/158191\/","title":{"rendered":"\u9ad8\u6548\u5be6\u73fe\u6578\u64da\u591a\u689d\u4ef6\u7d71\u8a08\u4e0d\u91cd\u8907\uff08\u591a\u689d\u4ef6\u7d71\u8a08\u4e0d\u91cd\u8907\u6578\u64da\u5eab\uff09"},"content":{"rendered":"

\u9ad8\u6548\u5be6\u73fe\u6578\u64da\u591a\u689d\u4ef6\u7d71\u8a08\u4e0d\u91cd\u8907\uff08\u591a\u689d\u4ef6\u7d71\u8a08\u4e0d\u91cd\u8907\u6578\u64da\u5eab\uff09<\/h1>\n

\u5728\u7576\u4eca\u6578\u64da\u9a45\u52d5\u7684\u4e16\u754c\u4e2d\uff0c\u4f01\u696d\u548c\u7d44\u7e54\u9700\u8981\u6709\u6548\u5730\u7ba1\u7406\u548c\u5206\u6790\u5927\u91cf\u6578\u64da\u3002\u5c24\u5176\u662f\u5728\u9032\u884c\u591a\u689d\u4ef6\u7d71\u8a08\u6642\uff0c\u5982\u4f55\u78ba\u4fdd\u6578\u64da\u7684\u6e96\u78ba\u6027\u548c\u4e0d\u91cd\u8907\u6027\u6210\u70ba\u4e86\u4e00\u500b\u91cd\u8981\u7684\u6311\u6230\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u9ad8\u6548\u5be6\u73fe\u6578\u64da\u7684\u591a\u689d\u4ef6\u7d71\u8a08\u4e0d\u91cd\u8907\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u6280\u8853\u548c\u793a\u4f8b\u3002<\/p>\n

\u591a\u689d\u4ef6\u7d71\u8a08\u7684\u6982\u5ff5<\/h2>\n

\u591a\u689d\u4ef6\u7d71\u8a08\u662f\u6307\u5728\u6578\u64da\u5eab\u4e2d\u6839\u64da\u591a\u500b\u689d\u4ef6\u9032\u884c\u6578\u64da\u7be9\u9078\u548c\u7d71\u8a08\u7684\u904e\u7a0b\u3002\u9019\u4e9b\u689d\u4ef6\u53ef\u4ee5\u662f\u6578\u64da\u7684\u4e0d\u540c\u5c6c\u6027\uff0c\u4f8b\u5982\u65e5\u671f\u7bc4\u570d\u3001\u985e\u5225\u3001\u5730\u5340\u7b49\u3002\u901a\u904e\u9019\u7a2e\u65b9\u5f0f\uff0c\u4f7f\u7528\u8005\u53ef\u4ee5\u7372\u5f97\u66f4\u5177\u91dd\u5c0d\u6027\u7684\u6578\u64da\u5206\u6790\u7d50\u679c\u3002<\/p>\n

\u6578\u64da\u4e0d\u91cd\u8907\u7684\u91cd\u8981\u6027<\/h2>\n

\u5728\u9032\u884c\u6578\u64da\u7d71\u8a08\u6642\uff0c\u91cd\u8907\u6578\u64da\u6703\u5c0e\u81f4\u7d71\u8a08\u7d50\u679c\u7684\u4e0d\u6e96\u78ba\uff0c\u5f9e\u800c\u5f71\u97ff\u6c7a\u7b56\u7684\u6709\u6548\u6027\u3002\u56e0\u6b64\uff0c\u78ba\u4fdd\u6578\u64da\u7684\u552f\u4e00\u6027\u662f\u9032\u884c\u591a\u689d\u4ef6\u7d71\u8a08\u7684\u524d\u63d0\u3002\u9019\u901a\u5e38\u9700\u8981\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u548c\u67e5\u8a62\u6642\u8003\u616e\u5230\u6578\u64da\u7684\u53bb\u91cd\u7b56\u7565\u3002<\/p>\n

\u5be6\u73fe\u591a\u689d\u4ef6\u7d71\u8a08\u4e0d\u91cd\u8907\u7684\u6280\u8853<\/h2>\n

1. \u6578\u64da\u5eab\u8a2d\u8a08<\/h3>\n

\u5728\u6578\u64da\u5eab\u8a2d\u8a08\u968e\u6bb5\uff0c\u61c9\u8a72\u8003\u616e\u4f7f\u7528\u4e3b\u9375\u6216\u552f\u4e00\u7d22\u5f15\u4f86\u78ba\u4fdd\u6578\u64da\u7684\u552f\u4e00\u6027\u3002\u4f8b\u5982\uff0c\u5728\u4e00\u500b\u7528\u6236\u6578\u64da\u8868\u4e2d\uff0c\u53ef\u4ee5\u5c07\u7528\u6236ID\u8a2d\u7f6e\u70ba\u4e3b\u9375\uff0c\u9019\u6a23\u53ef\u4ee5\u9632\u6b62\u91cd\u8907\u7684\u7528\u6236\u6578\u64da\u88ab\u63d2\u5165\u3002<\/p>\n

CREATE TABLE users (\n    user_id INT PRIMARY KEY,\n    username VARCHAR(50) UNIQUE,\n    email VARCHAR(100) UNIQUE\n);<\/code><\/pre>\n
2. \u4f7f\u7528SQL\u67e5\u8a62\u9032\u884c\u53bb\u91cd<\/h3>\n
\u5728\u9032\u884c\u591a\u689d\u4ef6\u7d71\u8a08\u6642\uff0c\u53ef\u4ee5\u4f7f\u7528SQL\u7684DISTINCT\u95dc\u9375\u5b57\u4f86\u53bb\u9664\u91cd\u8907\u7684\u6578\u64da\u3002\u4f8b\u5982\uff0c\u4ee5\u4e0b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u4e0d\u91cd\u8907\u7684\u7528\u6236\u540d\u548c\u96fb\u5b50\u90f5\u4ef6\uff1a<\/p>\n
SELECT DISTINCT username, email \nFROM users \nWHERE registration_date BETWEEN '2023-01-01' AND '2023-12-31';<\/code><\/pre>\n
3. \u6578\u64da\u8655\u7406\u6846\u67b6<\/h3>\n
\u5728\u8655\u7406\u5927\u6578\u64da\u6642\uff0c\u4f7f\u7528\u6578\u64da\u8655\u7406\u6846\u67b6\uff08\u5982Apache Spark\u6216Hadoop\uff09\u53ef\u4ee5\u6709\u6548\u5730\u9032\u884c\u591a\u689d\u4ef6\u7d71\u8a08\u548c\u53bb\u91cd\u64cd\u4f5c\u3002\u9019\u4e9b\u6846\u67b6\u63d0\u4f9b\u4e86\u5f37\u5927\u7684\u6578\u64da\u8655\u7406\u80fd\u529b\uff0c\u80fd\u5920\u5728\u5206\u4f48\u5f0f\u74b0\u5883\u4e2d\u9ad8\u6548\u5730\u8655\u7406\u6578\u64da\u3002<\/p>\n
val distinctUsers = users\n    .filter($\"registration_date\" >= \"2023-01-01\" && $\"registration_date\" <= "2023-12-31")\n    .distinct()<\/code><\/pre>\n
\u5be6\u969b\u6848\u4f8b\u5206\u6790<\/h2>\n
\u5047\u8a2d\u4e00\u5bb6\u516c\u53f8\u5e0c\u671b\u5206\u6790\u5176\u7528\u6236\u5728\u7279\u5b9a\u6642\u9593\u7bc4\u570d\u5167\u7684\u8a3b\u518a\u60c5\u6cc1\uff0c\u4e26\u78ba\u4fdd\u4e0d\u91cd\u8907\u8a08\u7b97\u540c\u4e00\u7528\u6236\u3002\u901a\u904e\u8a2d\u8a08\u5408\u9069\u7684\u6578\u64da\u5eab\u7d50\u69cb\u548c\u4f7f\u7528SQL\u67e5\u8a62\uff0c\u4ed6\u5011\u53ef\u4ee5\u8f15\u9b06\u7372\u5f97\u6240\u9700\u7684\u7d71\u8a08\u6578\u64da\u3002<\/p>\n
\u4f8b\u5982\uff0c\u8a72\u516c\u53f8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bSQL\u67e5\u8a62\u4f86\u7372\u53d62023\u5e74\u5167\u6240\u6709\u4e0d\u91cd\u8907\u7684\u7528\u6236\u8a3b\u518a\u6578\u91cf\uff1a<\/p>\n
SELECT COUNT(DISTINCT user_id) \nFROM users \nWHERE registration_date BETWEEN '2023-01-01' AND '2023-12-31';<\/code><\/pre>\n
\u7d50\u8ad6<\/h2>\n
\u9ad8\u6548\u5be6\u73fe\u6578\u64da\u7684\u591a\u689d\u4ef6\u7d71\u8a08\u4e0d\u91cd\u8907\u662f\u4e00\u500b\u95dc\u9375\u7684\u6280\u8853\u6311\u6230\u3002\u901a\u904e\u5408\u7406\u7684\u6578\u64da\u5eab\u8a2d\u8a08\u3001\u6709\u6548\u7684SQL\u67e5\u8a62\u548c\u5148\u9032\u7684\u6578\u64da\u8655\u7406\u6846\u67b6\uff0c\u4f01\u696d\u53ef\u4ee5\u78ba\u4fdd\u5176\u6578\u64da\u5206\u6790\u7684\u6e96\u78ba\u6027\u548c\u53ef\u9760\u6027\u3002\u9019\u4e0d\u50c5\u6709\u52a9\u65bc\u63d0\u9ad8\u6c7a\u7b56\u7684\u6709\u6548\u6027\uff0c\u9084\u80fd\u4fc3\u9032\u696d\u52d9\u7684\u6301\u7e8c\u589e\u9577\u3002<\/p>\n
\u5982\u9700\u4e86\u89e3\u66f4\u591a\u95dc\u65bc\u6578\u64da\u7ba1\u7406\u548c\u5206\u6790\u7684\u89e3\u6c7a\u65b9\u6848\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9 Server.HK<\/a>\uff0c\u63a2\u7d22\u6211\u5011\u7684 VPS<\/a> \u548c \u9999\u6e2f\u4f3a\u670d\u5668<\/a> \u670d\u52d9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
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