{"id":75802,"date":"2024-10-16T01:21:15","date_gmt":"2024-10-15T17:21:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/75802\/"},"modified":"2024-10-16T01:21:15","modified_gmt":"2024-10-15T17:21:15","slug":"mysql-%e6%9f%a5%e8%a9%a2%e5%88%86%e9%a0%81%e7%9a%84%e5%84%aa%e5%8c%96","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/75802\/","title":{"rendered":"MySQL \u67e5\u8a62\u5206\u9801\u7684\u512a\u5316"},"content":{"rendered":"

MySQL \u67e5\u8a62\u5206\u9801\u7684\u512a\u5316<\/h1>\n

\u5728\u73fe\u4ee3\u7684\u7db2\u7d61\u61c9\u7528\u4e2d\uff0c\u6578\u64da\u7684\u67e5\u8a62\u548c\u986f\u793a\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u5c24\u5176\u662f\u5728\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\uff0c\u5982\u4f55\u6709\u6548\u5730\u9032\u884c\u5206\u9801\u67e5\u8a62\u6210\u70ba\u4e86\u958b\u767c\u8005\u9700\u8981\u9762\u5c0d\u7684\u4e00\u500b\u6311\u6230\u3002\u672c\u6587\u5c07\u63a2\u8a0e MySQL \u67e5\u8a62\u5206\u9801\u7684\u512a\u5316\u65b9\u6cd5\uff0c\u5e6b\u52a9\u958b\u767c\u8005\u63d0\u9ad8\u6578\u64da\u67e5\u8a62\u7684\u6548\u7387\u3002<\/p>\n

\u5206\u9801\u67e5\u8a62\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n

\u5206\u9801\u67e5\u8a62\u662f\u6307\u5c07\u67e5\u8a62\u7d50\u679c\u5206\u6210\u591a\u500b\u9801\u9762\u986f\u793a\uff0c\u901a\u5e38\u4f7f\u7528 LIMIT \u548c OFFSET \u4f86\u5be6\u73fe\u3002\u4f8b\u5982\uff0c\u4ee5\u4e0b SQL \u67e5\u8a62\u5c07\u8fd4\u56de\u7b2c 2 \u9801\u7684 10 \u689d\u8a18\u9304\uff1a<\/p>\n

SELECT * FROM users LIMIT 10 OFFSET 10;<\/code><\/pre>\n
\u9019\u6a23\u7684\u67e5\u8a62\u5728\u6578\u64da\u91cf\u8f03\u5c0f\u7684\u60c5\u6cc1\u4e0b\u8868\u73fe\u826f\u597d\uff0c\u4f46\u96a8\u8457\u6578\u64da\u91cf\u7684\u589e\u52a0\uff0c\u6027\u80fd\u6703\u9010\u6f38\u4e0b\u964d\u3002<\/p>\n
\u70ba\u4ec0\u9ebc\u5206\u9801\u67e5\u8a62\u6703\u8b8a\u6162<\/h2>\n
\u7576\u6578\u64da\u8868\u4e2d\u7684\u8a18\u9304\u6578\u91cf\u589e\u9577\u6642\uff0c\u4f7f\u7528 OFFSET \u7684\u67e5\u8a62\u6703\u8b8a\u5f97\u8d8a\u4f86\u8d8a\u6162\u3002\u9019\u662f\u56e0\u70ba MySQL \u5728\u57f7\u884c\u67e5\u8a62\u6642\u9700\u8981\u8df3\u904e OFFSET \u6307\u5b9a\u7684\u8a18\u9304\u6578\uff0c\u9019\u610f\u5473\u8457\u5b83\u4ecd\u7136\u9700\u8981\u6383\u63cf\u6574\u500b\u8868\u4f86\u627e\u5230\u6240\u9700\u7684\u8a18\u9304\u3002\u9019\u7a2e\u60c5\u6cc1\u4e0b\uff0c\u67e5\u8a62\u7684\u6027\u80fd\u6703\u53d7\u5230\u5f71\u97ff\uff0c\u7279\u5225\u662f\u5728\u6578\u64da\u91cf\u9054\u5230\u6578\u5341\u842c\u751a\u81f3\u6578\u767e\u842c\u689d\u6642\u3002<\/p>\n
\u512a\u5316\u5206\u9801\u67e5\u8a62\u7684\u65b9\u6cd5<\/h2>\n
1. \u4f7f\u7528\u7d22\u5f15<\/h3>\n
\u78ba\u4fdd\u67e5\u8a62\u4e2d\u4f7f\u7528\u7684\u5b57\u6bb5\u6709\u9069\u7576\u7684\u7d22\u5f15\u3002\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\uff0c\u7279\u5225\u662f\u5728\u9032\u884c\u6392\u5e8f\u548c\u904e\u6ffe\u6642\u3002\u4f8b\u5982\uff0c\u5982\u679c\u6211\u5011\u7d93\u5e38\u6839\u64da\u7528\u6236\u7684\u5275\u5efa\u6642\u9593\u9032\u884c\u67e5\u8a62\uff0c\u53ef\u4ee5\u5728\u5275\u5efa\u6642\u9593\u5b57\u6bb5\u4e0a\u5efa\u7acb\u7d22\u5f15\uff1a<\/p>\n
CREATE INDEX idx_created_at ON users(created_at);<\/code><\/pre>\n
2. \u4f7f\u7528\u4e3b\u9375\u6216\u552f\u4e00\u7d22\u5f15\u9032\u884c\u5206\u9801<\/h3>\n
\u53e6\u4e00\u7a2e\u512a\u5316\u65b9\u6cd5\u662f\u4f7f\u7528\u4e3b\u9375\u6216\u552f\u4e00\u7d22\u5f15\u4f86\u9032\u884c\u5206\u9801\uff0c\u800c\u4e0d\u662f\u4f7f\u7528 OFFSET\u3002\u9019\u7a2e\u65b9\u6cd5\u53ef\u4ee5\u907f\u514d\u5168\u8868\u6383\u63cf\u3002\u4f8b\u5982\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\u4f86\u7372\u53d6\u4e0b\u4e00\u9801\u7684\u6578\u64da\uff1a<\/p>\n
SELECT * FROM users WHERE id > last_seen_id ORDER BY id LIMIT 10;<\/code><\/pre>\n
\u9019\u6a23\u7684\u67e5\u8a62\u53ea\u9700\u67e5\u627e\u5927\u65bc\u6700\u5f8c\u4e00\u689d\u8a18\u9304\u7684\u6578\u64da\uff0c\u6027\u80fd\u6703\u66f4\u597d\u3002<\/p>\n
3. \u4f7f\u7528\u5b50\u67e5\u8a62<\/h3>\n
\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u53ef\u4ee5\u4f7f\u7528\u5b50\u67e5\u8a62\u4f86\u512a\u5316\u5206\u9801\u67e5\u8a62\u3002\u4f8b\u5982\uff0c\u9996\u5148\u67e5\u8a62\u51fa\u9700\u8981\u7684 ID\uff0c\u7136\u5f8c\u518d\u6839\u64da\u9019\u4e9b ID \u67e5\u8a62\u5177\u9ad4\u7684\u6578\u64da\uff1a<\/p>\n
SELECT * FROM users WHERE id IN (SELECT id FROM users ORDER BY created_at LIMIT 10 OFFSET 10);<\/code><\/pre>\n
4. \u4f7f\u7528\u6301\u4e45\u5316\u7684\u5206\u9801\u72c0\u614b<\/h3>\n
\u5982\u679c\u7528\u6236\u7d93\u5e38\u67e5\u770b\u76f8\u540c\u7684\u6578\u64da\u96c6\uff0c\u53ef\u4ee5\u8003\u616e\u5c07\u67e5\u8a62\u7d50\u679c\u7de9\u5b58\uff0c\u9019\u6a23\u53ef\u4ee5\u6e1b\u5c11\u5c0d\u6578\u64da\u5eab\u7684\u67e5\u8a62\u6b21\u6578\u3002\u4f7f\u7528 Redis \u6216 Memcached \u7b49\u7de9\u5b58\u6280\u8853\uff0c\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u6027\u80fd\u3002<\/p>\n
\u7d50\u8ad6<\/h2>\n
\u512a\u5316 MySQL \u67e5\u8a62\u5206\u9801\u662f\u4e00\u500b\u91cd\u8981\u7684\u8ab2\u984c\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u91cf\u6578\u64da\u6642\u3002\u901a\u904e\u4f7f\u7528\u7d22\u5f15\u3001\u4e3b\u9375\u5206\u9801\u3001\u5b50\u67e5\u8a62\u548c\u7de9\u5b58\u7b49\u6280\u8853\uff0c\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002\u9019\u4e0d\u50c5\u80fd\u6539\u5584\u7528\u6236\u9ad4\u9a57\uff0c\u9084\u80fd\u6e1b\u5c11\u4f3a\u670d\u5668\u7684\u8ca0\u64d4\u3002<\/p>\n
\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 \u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0cServer.HK \u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\uff0c\u5e6b\u52a9\u60a8\u8f15\u9b06\u7ba1\u7406\u6578\u64da\u5eab\u548c\u61c9\u7528\u7a0b\u5e8f\u3002\u7121\u8ad6\u662f \u4e91\u4f3a\u670d\u5668<\/a> \u9084\u662f \u9999\u6e2f\u4f3a\u670d\u5668<\/a>\uff0c\u6211\u5011\u90fd\u80fd\u6eff\u8db3\u60a8\u7684\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u63a2\u7d22 MySQL \u67e5\u8a62\u5206\u9801\u7684\u6700\u4f73\u5be6\u8e10\u8207\u512a\u5316\u6280\u5de7\uff0c\u63d0\u9ad8\u6578\u64da\u6aa2\u7d22\u6548\u7387\uff0c\u63d0\u5347\u61c9\u7528\u6027\u80fd\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-75802","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75802","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=75802"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75802\/revisions"}],"predecessor-version":[{"id":75803,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/75802\/revisions\/75803"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=75802"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=75802"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=75802"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}