** data set description two datasets, one from clickhouse, one from Nginx-cache, clickhouse dataset has more data, colo information, but missing 1. TTL, 2. zone plan, 3. cacheKey (objID), 4. originReponseChunked, 5. range request. Because size of clickhouse dataset, it is sampled from 1% to 40 by object id.
** the clickhouse data format timestamp client country (anonymized) coloId, obj_id (md5 of host+path+query) obj_id2 (md5 of host+path) responseSize content type file extension n level (the number of '/' in path) ttl (augment from crawling, not always accurate and still missing 10% data) age cache status method (get/purge) zone id (md5 hash) client request host (md5 hash) edgehost (md5 hash) referhost (md5 hash) has query string (bool) n param in query
** the nginx data format client country hot object (bool) timestamp obj_id response body size http method content type file extension n level expire ttl age cache status zone id (md5 hash) zone plan chunked response has query n param in query cache control hostname (sha1 hash) http range