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什么是ETag？ETag作用有哪些

ETag是HTTP头的一部分，它是一个字符串标识一个web资源的特定版本。它由web服务器生成，用于标识文件的实体标签。ETag可以用来确定同一资源是否已被修改，这在缓存和验证客户端缓存文件是否过期时很有用。ETag的作用如下： 1.缓存控制：在HTTP响应头部中包含ETag可以帮助浏览器缓存和验证资源。如果资源没有发生任何改变，浏览器可以直接从本地缓存中获取资源，而不需要重新从服务器获取。 2.资源验证：如果浏览器的缓存过期或需要更新，它可以使用请求头中的ETag来验证资源是否已被修改。如果资源没有被修改，服务器可以发送一个响应代码为304的响应，告诉浏览器它可以继续使用缓存中的资源。 3.负载均衡：在使用多个Web服务器负载均衡时，ETag可以确保客户端的请求被重定向到与其之前请求相同的服务器。如果不使用ETag，则可能会发生客户端请求一个资源，但它需要从新的服务器获取，即使其他服务器已经有缓存。

Public @ 2023-06-10 23:50:20

百度搜索资源平台-平台升级亮点多！业内大佬送祝福！

百度搜索资源平台是百度推出的一个资源分享和搜索平台，旨在帮助用户更方便地找到各类资源，并提供资源的下载和分享功能。最近，百度搜索资源平台进行了一次升级，引起了业内的广泛关注和好评。这次平台升级的亮点主要体现在以下几个方面： 1. 搜索结果更精准：升级后的搜索算法更加智能，能够更准确、更迅速地找到用户所需的资源。用户在搜索关键词后，能够获得更多与其相关的资源，大大提高了搜索效率。 2. 资源

Public @ 2023-07-21 14:00:41

百度搜索资源平台-请站长配合解封百度免流IP段

各位站长好。百度圣卡是百度与运营商合作推出的项目，可以实现用户在使用百度系等APP时不消耗手机流量。近期，我们收到部分百度圣卡用户反馈，通过百度APP搜索访问部分网站时，出现错误页面，导致用户无法正常浏览网站。截图见下：通过技术人员排查，我们发现是这些网站将我们的搜索免流IP段进行了封禁（可能不是网站工作人员人为封禁，有可能是网站的安全策略自动触发）。随着百度圣卡用户增多，这类问题逐渐增多，很多网

Public @ 2018-05-08 16:05:32

头条搜索站长平台-sitemapindex文件要求

sitemapindex文件根节点必须是<sitemapindex>。sitemapindex文件编码必须为UTF-8，第一行为: <?xml version="1.0" encoding="utf-8" ?>。sitemapindex文件禁止使用命名空间，禁止使用规定之外的属性。sitemapindex文件大小不得超过5M，site

Public @ 2013-06-03 16:09:47

百度搜索资源平台-sitemap全网开放及建议启用Etag的公告

尊敬的用户：为了更好地优化搜索资源平台的索引和抓取效率，提高网站页面的收录速度，我们决定将百度搜索资源平台的sitemap功能全网开放。从即日起，所有网站都可以使用sitemap协议向百度搜索推送网站的页面信息。同时，我们也建议网站在sitemap中启用Etag机制。Etag是一种用于判断网页是否发生变化的机制，在网站页面发生变动时可以通过更新Etag来通知搜索引擎重新抓取该页面，从而保持

Public @ 2023-07-26 21:00:31

更多您感兴趣的搜索

基本文件流程错误 SQL 调试

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[ DB ] CONNECT:[ UseTime:0.026921s ] mysql:dbname=briline.net;host=106.14.77.182;port=3306;charset=utf8
[ SQL ] SHOW COLUMNS FROM `ob_article` [ RunTime:0.019035s ]
[ SQL ] SELECT * FROM `ob_article` WHERE `id` = 8735 LIMIT 1 [ RunTime:0.018120s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article', 'type' => 'const', 'possible_keys' => 'PRIMARY', 'key' => 'PRIMARY', 'key_len' => '4', 'ref' => 'const', 'rows' => 1, 'extra' => NULL, ) ]
[ SQL ] select * from `ob_article_tongji` where category_id=12 and mark_type='cate' order by times desc limit 15 [ RunTime:0.018280s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article_tongji', 'type' => 'ALL', 'possible_keys' => NULL, 'key' => NULL, 'key_len' => NULL, 'ref' => NULL, 'rows' => 608, 'extra' => 'Using where; Using filesort', ) ]
[ SQL ] select * from `ob_article_tongji` where category_id=12 and mark_type='tags' order by times desc limit 100 [ RunTime:0.018544s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article_tongji', 'type' => 'ALL', 'possible_keys' => NULL, 'key' => NULL, 'key_len' => NULL, 'ref' => NULL, 'rows' => 608, 'extra' => 'Using where; Using filesort', ) ]
[ SQL ] select * from `ob_article_tongji` where category_id=12 and mark_type='tags' order by rand() limit 30 [ RunTime:0.018867s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article_tongji', 'type' => 'ALL', 'possible_keys' => NULL, 'key' => NULL, 'key_len' => NULL, 'ref' => NULL, 'rows' => 608, 'extra' => 'Using where; Using temporary; Using filesort', ) ]
[ SQL ] SELECT * FROM `ob_article` WHERE `id` = 8735 LIMIT 1 [ RunTime:0.018040s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article', 'type' => 'const', 'possible_keys' => 'PRIMARY', 'key' => 'PRIMARY', 'key_len' => '4', 'ref' => 'const', 'rows' => 1, 'extra' => NULL, ) ]
[ SQL ] update `ob_article` set views=views+2 where id=8735 [ RunTime:0.018924s ]
[ SQL ] SELECT COUNT(*) AS tp_count FROM `ob_article` WHERE `category_id` = 12 AND `cate` = '威海百度搜索资源平台' AND `status` <> -1 LIMIT 1 [ RunTime:0.024858s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article', 'type' => 'ALL', 'possible_keys' => NULL, 'key' => NULL, 'key_len' => NULL, 'ref' => NULL, 'rows' => 8035, 'extra' => 'Using where', ) ]
[ SQL ] SELECT * FROM `ob_article` WHERE `category_id` = 12 AND `cate` = '威海百度搜索资源平台' AND `status` <> -1 ORDER BY rand() LIMIT 0,2 [ RunTime:0.043529s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article', 'type' => 'ALL', 'possible_keys' => NULL, 'key' => NULL, 'key_len' => NULL, 'ref' => NULL, 'rows' => 8035, 'extra' => 'Using where; Using temporary; Using filesort', ) ]
[ SQL ] SELECT COUNT(*) AS tp_count FROM `ob_article` WHERE `category_id` = 12 AND `tags` = '威海Sitemap' AND `status` <> -1 LIMIT 1 [ RunTime:0.027310s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article', 'type' => 'ALL', 'possible_keys' => NULL, 'key' => NULL, 'key_len' => NULL, 'ref' => NULL, 'rows' => 8035, 'extra' => 'Using where', ) ]
[ SQL ] SELECT * FROM `ob_article` WHERE `category_id` = 12 AND `tags` = '威海Sitemap' AND `status` <> -1 ORDER BY rand() LIMIT 0,2 [ RunTime:0.035397s ]
[ EXPLAIN : array ( 'id' => 1, 'select_type' => 'SIMPLE', 'table' => 'ob_article', 'type' => 'ALL', 'possible_keys' => NULL, 'key' => NULL, 'key_len' => NULL, 'ref' => NULL, 'rows' => 8035, 'extra' => 'Using where; Using temporary; Using filesort', ) ]

0.488039s

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