What is the meaning of Write Ahead Log in Hadoop

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Can someone explain to me in brief about Write Ahead Log (WAL)?
Nov 21, 2018 in Big Data Hadoop by Haman
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1 answer to this question.

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Write Ahead Log (WAL) is a file attached to every Region Server inside the distributed environment. The WAL stores the new data that hasn’t been persisted or committed to the permanent storage. It is used in case of failure to recover the data sets.

answered Nov 21, 2018 by Sunil

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