Explain storage mechanism in HBase and Column-Oriented Database &, Row-Oriented Database.

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 STORAGE MECHANISM IN HBASE

HBase is a column-oriented database, with tables ordered by row. Only column families, which are key-value pairs, are defined in the table structure. A table contains many columns families, each of which can include any number of columns. Subsequent column values are saved on the disk in a logical order. A timestamp is associated with each cell value in the table.

In a nutshell, in an HBase:

  • The table is a collection of rows.
  • The row is a collection of column families.
  • A Column family is a collection of columns. 
  • The column is a collection of key-value pairs.


An example schema of a table in HBase is provided below.




COLUMN-ORIENTED AND ROW-ORIENTED DATABASE

Column-oriented databases, as opposed to row-oriented databases, store data tables as portions of columns of data. They will have column families.

Row-Oriented Database

  • It is suitable for the Online Transaction Process(OLTP).
  • Such databases are designed for a small number of rows and columns.

Column-Oriented Database

  • It is suitable for Online Analytical Processing (OLAP).
  • Column-oriented databases are designed for huge tables.


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