2012年5月18日

DataJoin: Reduce-side join

摘要： 首先三个概念：A data source is analogous to a table in relational databases.( a single file or multiple files)tag:Tagging the record will ensure that specifi c metadata will always go along with the record.group key: like a join key in a relational database 两个数据源data sources: Customers ... 阅读全文

posted @ 2012-05-18 21:56 liangzh123 阅读(427) 评论(0) 推荐(0)

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