c***z 发帖数: 6348 | 1 【 以下文字转载自 DataSciences 讨论区 】
发信人: chaoz (面朝大海,吃碗凉皮), 信区: DataSciences
标 题: [Pig Progamming] Pig Latin join problem
发信站: BBS 未名空间站 (Tue Jan 28 20:00:22 2014, 美东)
Hi all,
Just wondering if any of you had the same problem and if you know the cause.
I have a dataset of site-visitor pairs, which records daily visits to
websites.
While filtering the data using domain "espn.com", there are 306 unique
visitors; while joining the data with the list of domain names, I only got
176 unique visitors to "espn.com".
This is weird since conceptually both filtering and joining use hash tables
the same way.
PS: pig didn't drop bags during the join, at least it didn't tell me about
dropping bags.
Thanks a lot! |
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