{"id":7452,"date":"2024-11-14T16:04:28","date_gmt":"2024-11-14T08:04:28","guid":{"rendered":"https:\/\/fwq.ai\/blog\/7452\/"},"modified":"2024-11-14T16:04:28","modified_gmt":"2024-11-14T08:04:28","slug":"%e5%a6%82%e4%bd%95%e9%ab%98%e6%95%88%e5%9c%b0%e4%bb%8e%e5%a4%a7%e5%9e%8b-mysql-%e8%a1%a8%e4%b8%ad%e6%9f%a5%e8%af%a2%e6%8c%87%e5%ae%9a%e6%97%b6%e9%97%b4%e5%b7%ae%e7%9a%84%e6%95%b0%e6%8d%ae%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/7452\/","title":{"rendered":"\u5982\u4f55\u9ad8\u6548\u5730\u4ece\u5927\u578b MySQL \u8868\u4e2d\u67e5\u8be2\u6307\u5b9a\u65f6\u95f4\u5dee\u7684\u6570\u636e\uff1f"},"content":{"rendered":"

\"\u5982\u4f55\u9ad8\u6548\u5730\u4ece\u5927\u578b<\/p>\n

\u67e5\u8be2\u6307\u5b9a\u65f6\u95f4\u5dee\u7684\u6570\u636e<\/strong><\/p>\n

\u5f53\u5904\u7406\u5927\u578b\u8868\u65f6\uff0c\u627e\u51fa\u5b58\u5728\u65f6\u95f4\u5dee\u7684\u6570\u636e\u53ef\u80fd\u9887\u5177\u6311\u6218\u3002\u5982\u679c\u6ca1\u6709\u4fbf\u6377\u7684\u5f00\u7a97\u51fd\u6570\u53ef\u7528\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u65b9\u6cd5\uff1a<\/p>\n

\u65b9\u6cd5 1\uff1a\u4f7f\u7528\u4e34\u65f6\u53d8\u91cf<\/strong><\/p>\n

set @tmp = '2000-1-1';\nselect * from (\n    select *,\n    timestampdiff(second, @tmp, time) as diff,\n    @tmp := time\n    from \u8868\u540d\n) as t1\nwhere diff > 300;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u6b64\u65b9\u6cd5\u901a\u8fc7\u4f7f\u7528\u4e34\u65f6\u53d8\u91cf @tmp \u4fdd\u5b58\u4e0a\u4e00\u6761\u8bb0\u5f55\u7684\u65f6\u95f4\u5e76\u8ba1\u7b97\u5176\u4e0e\u5f53\u524d\u8bb0\u5f55\u7684\u65f6\u95f4\u5dee\u6765\u5b9e\u73b0\u3002<\/p>\n
\u65b9\u6cd5 2\uff1a\u4ea4\u53c9\u8fde\u63a5<\/strong><\/p>\n
\u5982\u679c\u53ef\u4ee5\u751f\u6210\u65b0\u8868\uff0c\u5219\u53ef\u4ee5\u521b\u5efa\u81ea\u52a8\u589e\u91cf\u4e3b\u952e\u5b57\u6bb5\uff0c\u7136\u540e\u4f7f\u7528\u4ea4\u53c9\u8fde\u63a5\uff1a<\/p>\n
select *\nfrom \u8868 as a\nleft join \u8868 as b\non a.\u4e3b\u952e = b.\u4e3b\u952e + 1\nwhere timestampdiff(second, a.time, b.time) > 300;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u6b64\u65b9\u6cd5\u5c06\u5f53\u524d\u8bb0\u5f55\u4e0e\u540e\u7eed\u8bb0\u5f55\u4ea4\u53c9\u8fde\u63a5\uff0c\u5e76\u6bd4\u8f83\u65f6\u95f4\u5dee\u3002<\/p>\n
\u65b9\u6cd5 3\uff1a\u4f7f\u7528 lag \u53d8\u91cf<\/strong><\/p>\n
\u867d\u7136\u539f\u59cb\u95ee\u9898\u4e2d\u6307\u51fa\u4e0d\u652f\u6301 lag \u5f00\u7a97\u51fd\u6570\uff0c\u4f46\u4ecd\u53ef\u901a\u8fc7\u590d\u5236\u8868\u6765\u5b9e\u73b0\u7c7b\u4f3c\u529f\u80fd\uff1a<\/p>\n
set @i = 0; set @j = 0;\nselect *, a2 - a1\nfrom (\n    select *, @i := @i + 1 as a1\n    from lag1\n) as t1\nleft join (\n    select *, @j := @j + 1 as a2\n    from lag1\n) as t2\non t1.a1 + 1 = t2.a2 ;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u6b64\u65b9\u6cd5\u901a\u8fc7\u751f\u6210\u4e24\u4e2a\u8f85\u52a9\u8868\u5e76\u4f7f\u7528\u8fde\u63a5\u6765\u6a21\u62df lag \u53d8\u91cf\u6765\u5b9e\u73b0\u3002<\/p>\n
\u4ee5\u4e0a\u5c31\u662f\u5982\u4f55\u9ad8\u6548\u5730\u4ece\u5927\u578b MySQL \u8868\u4e2d\u67e5\u8be2\u6307\u5b9a\u65f6\u95f4\u5dee\u7684\u6570\u636e\uff1f\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u7f51\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u67e5\u8be2\u6307\u5b9a\u65f6\u95f4\u5dee\u7684\u6570\u636e \u5f53\u5904\u7406\u5927\u578b\u8868\u65f6\uff0c\u627e\u51fa\u5b58\u5728\u65f6\u95f4\u5dee\u7684\u6570\u636e\u53ef\u80fd\u9887\u5177\u6311\u6218\u3002\u5982\u679c\u6ca1\u6709\u4fbf\u6377\u7684\u5f00\u7a97\u51fd\u6570\u53ef\u7528\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u65b9\u6cd5\uff1a \u65b9\u6cd5 1\uff1a\u4f7f\u7528\u4e34\u65f6\u53d8\u91cf set @tmp = ‘2000-1-1’; select * from ( select *, timestampdiff(second, @tmp, time) as diff, @tmp := time from \u8868\u540d ) as t1 where diff > 300; \u767b\u5f55\u540e\u590d\u5236 \u6b64\u65b9\u6cd5\u901a\u8fc7\u4f7f\u7528\u4e34\u65f6\u53d8\u91cf @tmp \u4fdd\u5b58\u4e0a\u4e00\u6761\u8bb0\u5f55\u7684\u65f6\u95f4\u5e76\u8ba1\u7b97\u5176\u4e0e\u5f53\u524d\u8bb0\u5f55\u7684\u65f6\u95f4\u5dee\u6765\u5b9e\u73b0\u3002 \u65b9\u6cd5 2\uff1a\u4ea4\u53c9\u8fde\u63a5 \u5982\u679c\u53ef\u4ee5\u751f\u6210\u65b0\u8868\uff0c\u5219\u53ef\u4ee5\u521b\u5efa\u81ea\u52a8\u589e\u91cf\u4e3b\u952e\u5b57\u6bb5\uff0c\u7136\u540e\u4f7f\u7528\u4ea4\u53c9\u8fde\u63a5\uff1a select * from \u8868 as a left join \u8868 as b on a.\u4e3b\u952e = b.\u4e3b\u952e + 1 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-7452","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/7452","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=7452"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/7452\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=7452"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=7452"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=7452"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}