{"id":171139,"date":"2024-11-07T00:15:20","date_gmt":"2024-11-06T16:15:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/171139\/"},"modified":"2024-11-07T00:15:20","modified_gmt":"2024-11-06T16:15:20","slug":"%e5%a5%87%e6%8a%80%e5%b7%a7%e5%a4%9a%ef%bc%81-%e6%95%b8%e6%93%9a%e5%ba%ab%e6%8e%92%e5%ba%8f%e8%a6%8f%e5%89%87%e6%98%af%e7%a5%9e","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/171139\/","title":{"rendered":"\u5947\u6280\u5de7\u591a\uff01 (\u6578\u64da\u5eab\u6392\u5e8f\u898f\u5247\u662f\u795e)"},"content":{"rendered":"

\u5947\u6280\u5de7\u591a\uff01(\u6578\u64da\u5eab\u6392\u5e8f\u898f\u5247\u662f\u795e)<\/h1>\n

\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u6392\u5e8f\u662f\u4e00\u500b\u81f3\u95dc\u91cd\u8981\u7684\u64cd\u4f5c\u3002\u7121\u8ad6\u662f\u67e5\u8a62\u7d50\u679c\u7684\u986f\u793a\uff0c\u9084\u662f\u6578\u64da\u7684\u5206\u6790\uff0c\u6392\u5e8f\u90fd\u80fd\u5e6b\u52a9\u6211\u5011\u66f4\u597d\u5730\u7406\u89e3\u548c\u5229\u7528\u6578\u64da\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u6578\u64da\u5eab\u4e2d\u7684\u6392\u5e8f\u898f\u5247\uff0c\u4e26\u5206\u4eab\u4e00\u4e9b\u5be6\u7528\u7684\u6280\u5de7\uff0c\u8b93\u4f60\u5728\u6578\u64da\u8655\u7406\u4e0a\u5982\u864e\u6dfb\u7ffc\u3002<\/p>\n

\u6578\u64da\u5eab\u6392\u5e8f\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n

\u6578\u64da\u5eab\u4e2d\u7684\u6392\u5e8f\u901a\u5e38\u662f\u6307\u6839\u64da\u67d0\u4e00\u6216\u591a\u500b\u5b57\u6bb5\u7684\u503c\u5c0d\u67e5\u8a62\u7d50\u679c\u9032\u884c\u6392\u5217\u3002\u6700\u5e38\u898b\u7684\u6392\u5e8f\u65b9\u5f0f\u662f\u5347\u5e8f\uff08ASC\uff09\u548c\u964d\u5e8f\uff08DESC\uff09\u3002\u4f8b\u5982\uff0c\u7576\u6211\u5011\u67e5\u8a62\u4e00\u500b\u7528\u6236\u8868\u6642\uff0c\u53ef\u4ee5\u6839\u64da\u7528\u6236\u7684\u8a3b\u518a\u6642\u9593\u9032\u884c\u6392\u5e8f\uff0c\u9019\u6a23\u53ef\u4ee5\u5feb\u901f\u627e\u5230\u6700\u65b0\u6216\u6700\u820a\u7684\u7528\u6236\u3002<\/p>\n

SELECT * FROM users ORDER BY registration_date ASC;<\/code><\/pre>\n
\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u67e5\u8a62\u7d50\u679c\u5c07\u6839\u64da\u8a3b\u518a\u65e5\u671f\u5f9e\u6700\u65e9\u5230\u6700\u65b0\u9032\u884c\u6392\u5217\u3002\u76f8\u53cd\uff0c\u5982\u679c\u6211\u5011\u5e0c\u671b\u67e5\u770b\u6700\u65b0\u7684\u7528\u6236\uff0c\u53ef\u4ee5\u4f7f\u7528\u964d\u5e8f\u6392\u5e8f\uff1a<\/p>\n
SELECT * FROM users ORDER BY registration_date DESC;<\/code><\/pre>\n
\u8907\u96dc\u6392\u5e8f\u7684\u61c9\u7528<\/h2>\n
\u9664\u4e86\u57fa\u672c\u7684\u5347\u5e8f\u548c\u964d\u5e8f\u6392\u5e8f\uff0c\u6578\u64da\u5eab\u9084\u652f\u6301\u8907\u96dc\u7684\u6392\u5e8f\u898f\u5247\u3002\u4f8b\u5982\uff0c\u6211\u5011\u53ef\u4ee5\u6839\u64da\u591a\u500b\u5b57\u6bb5\u9032\u884c\u6392\u5e8f\u3002\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u7522\u54c1\u8868\uff0c\u4e26\u5e0c\u671b\u6839\u64da\u985e\u5225\u548c\u50f9\u683c\u9032\u884c\u6392\u5e8f\uff0c\u53ef\u4ee5\u9019\u6a23\u5beb\uff1a<\/p>\n
SELECT * FROM products ORDER BY category ASC, price DESC;<\/code><\/pre>\n
\u9019\u6a23\u7684\u67e5\u8a62\u5c07\u9996\u5148\u6839\u64da\u7522\u54c1\u985e\u5225\u9032\u884c\u5347\u5e8f\u6392\u5217\uff0c\u7136\u5f8c\u5728\u6bcf\u500b\u985e\u5225\u5167\u90e8\u6839\u64da\u50f9\u683c\u9032\u884c\u964d\u5e8f\u6392\u5217\u3002\u9019\u7a2e\u591a\u5c64\u6b21\u7684\u6392\u5e8f\u65b9\u5f0f\u80fd\u5920\u5e6b\u52a9\u7528\u6236\u66f4\u5feb\u5730\u627e\u5230\u6240\u9700\u7684\u7522\u54c1\u3002<\/p>\n
\u4f7f\u7528\u6392\u5e8f\u7684\u6280\u5de7<\/h2>\n
1. \u5229\u7528\u7d22\u5f15\u63d0\u9ad8\u6392\u5e8f\u6548\u7387<\/h3>\n
\u5728\u5927\u578b\u6578\u64da\u5eab\u4e2d\uff0c\u6392\u5e8f\u64cd\u4f5c\u53ef\u80fd\u6703\u6d88\u8017\u5927\u91cf\u8cc7\u6e90\u3002\u70ba\u4e86\u63d0\u9ad8\u6392\u5e8f\u7684\u6548\u7387\uff0c\u53ef\u4ee5\u8003\u616e\u5728\u6392\u5e8f\u5b57\u6bb5\u4e0a\u5efa\u7acb\u7d22\u5f15\u3002\u7d22\u5f15\u80fd\u5920\u52a0\u901f\u67e5\u8a62\u548c\u6392\u5e8f\u7684\u904e\u7a0b\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\u3002<\/p>\n
CREATE INDEX idx_registration_date ON users (registration_date);<\/code><\/pre>\n
2. \u907f\u514d\u4e0d\u5fc5\u8981\u7684\u6392\u5e8f<\/h3>\n
\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u6392\u5e8f\u53ef\u80fd\u662f\u591a\u9918\u7684\u3002\u4f8b\u5982\uff0c\u5982\u679c\u67e5\u8a62\u7d50\u679c\u672c\u8eab\u5df2\u7d93\u662f\u6709\u5e8f\u7684\uff0c\u5247\u4e0d\u9700\u8981\u518d\u6b21\u9032\u884c\u6392\u5e8f\u3002\u9019\u6a23\u53ef\u4ee5\u7bc0\u7701\u8cc7\u6e90\uff0c\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002<\/p>\n
3. \u4f7f\u7528LIMIT\u9650\u5236\u7d50\u679c\u96c6<\/h3>\n
\u7576\u67e5\u8a62\u7d50\u679c\u96c6\u975e\u5e38\u9f90\u5927\u6642\uff0c\u53ef\u4ee5\u4f7f\u7528LIMIT\u8a9e\u53e5\u4f86\u9650\u5236\u8fd4\u56de\u7684\u884c\u6578\u3002\u9019\u6a23\u4e0d\u50c5\u80fd\u63d0\u9ad8\u6027\u80fd\uff0c\u9084\u80fd\u8b93\u7528\u6236\u66f4\u5feb\u5730\u7372\u5f97\u6240\u9700\u7684\u4fe1\u606f\u3002\u4f8b\u5982\uff1a<\/p>\n
SELECT * FROM products ORDER BY price ASC LIMIT 10;<\/code><\/pre>\n
\u9019\u6a23\u7684\u67e5\u8a62\u5c07\u8fd4\u56de\u50f9\u683c\u6700\u4f4e\u7684\u524d\u5341\u500b\u7522\u54c1\uff0c\u907f\u514d\u4e86\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u8655\u7406\u3002<\/p>\n
\u7d50\u8ad6<\/h2>\n
\u6578\u64da\u5eab\u7684\u6392\u5e8f\u898f\u5247\u5728\u6578\u64da\u7ba1\u7406\u4e2d\u626e\u6f14\u8457\u91cd\u8981\u89d2\u8272\u3002\u901a\u904e\u5408\u7406\u5229\u7528\u6392\u5e8f\u6280\u5de7\uff0c\u6211\u5011\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\uff0c\u512a\u5316\u6578\u64da\u8655\u7406\u904e\u7a0b\u3002\u7121\u8ad6\u662f\u5728\u65e5\u5e38\u7684\u6578\u64da\u5206\u6790\u9084\u662f\u5927\u578b\u6578\u64da\u8655\u7406\u4e2d\uff0c\u638c\u63e1\u9019\u4e9b\u6392\u5e8f\u6280\u5de7\u90fd\u80fd\u8b93\u6211\u5011\u4e8b\u534a\u529f\u500d\u3002<\/p>\n
\u5982\u679c\u4f60\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u6216\u5176\u4ed6\u6280\u8853\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\u3002\u6211\u5011\u63d0\u4f9b\u5404\u7a2e VPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0c\u5e6b\u52a9\u4f60\u66f4\u597d\u5730\u7ba1\u7406\u548c\u904b\u7528\u4f60\u7684\u6578\u64da\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u63a2\u7d22\u5947\u6280\u5de7\u591a\uff01\u63ed\u793a\u6578\u64da\u5eab\u6392\u5e8f\u898f\u5247\u7684\u5967\u79d8\uff0c\u8b93\u4f60\u8f15\u9b06\u638c\u63e1\u6578\u64da\u7ba1\u7406\u7684\u795e\u5947\u65b9\u6cd5\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-171139","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/171139","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=171139"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/171139\/revisions"}],"predecessor-version":[{"id":171140,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/171139\/revisions\/171140"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=171139"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=171139"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=171139"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}