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http://wiki.apache.org/lucene-hadoop/Bigtable%26Sawzall
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- Describe Bigtable&Sawzall here.
+ BigTable Overview
+ What is a BigTable?
+ BigTable is a multi-dimensional, sparse map storage with its focus on DFS’s massive data
storage and easier data analysis and development. It could also be defined as a distributed
database that is more economical than traditional large databases that allows faster analysis
on more diverse data. It does not manage every pre-calculation but it stores data in a distributed
way with a structure that allows distributed computation.
- Test.
+ Why do we need it?
+ * The amount of data is enormous and it grows exponentially. On top of the simple storage
needs, we would like to do some data analysis as well.
+ * We want our DB to be light-weight. We want our DB to adopt to the ever-changing needs
and requirements of new services.
+ Conclusion : We want to extract more value out of a company’s data by providing more availability
and usability when the company’s needs arise.
+
+ An usage example of BigTable – User action log data table for a service
+ To help make a business decision, to find a way to meet the need of each customer, or to
find a product or a market that will bring big profits, we group together action logs of users
and create a User Table like the one below.
+
+ row [ user ], attribute columns [ search history, item buying log, post scrap log, Page
Viewing log, User neighborhood (blog), User active part (cafe) ]
+
+ If we select two columns, the fact table in the above schema can be represented in a two-dimensional
table.
+
+ [http://mirror.udanax.org/~udanax/rsync1/download/NB_BoardData_006002/Figure1.jpg]
+
+ “Who referred to document A?” “What other documents do they also like?” “What
does a user who actively participates in a online community X like to search?” “Who are
the neighbors of this blog’s author?” “What are social distances between them?”
+ By finding out where new markets are being formed by managing and analyzing those user-related
data, we can analyze the evolution of services faster and more economically.
+
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