Differences between HDFS and HBase.&, Difference between HBase and RDBMS.

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Differences between HDFS and HBase.

HDFS

  •  HDFS is a distributed file system suitable for storing large files.
  • HDFS does not support fast individual record lookups.
  • It provides high latency batch processing; no concept of batch processing.
  • It provides only sequential access to data.


HBase

  • HBase is a database built on top of the HDFS.
  • HBase provides fast lookups for larger tables.
  • It provides low latency access to single rows from billions of records (Random access). 
  • HBase internally uses Hash tables and provides random .



Difference between HBase and RDBMS.

HBase

  • HBase is schema-less, it does not have the concept of fixed columns schema; defines only column families.
  • It is built for wide tables. HBase is horizontally scalable.
  • No transactions are there in HBase.
  • It has de-normalized data.
  • It is good for semi-structured as well as structured data.


RDBMS

  • An RDBMS is governed by its schema, which describes the whole structure of tables.
  • It is thin and built for small tables. Hard to scale.
  • RDBMS is transactional.
  • It will have normalized data.
  • It is good for structured data.



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