Difference between revisions of "DistOS 2015W Session 11"

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** Muti dimensional Sorted Map
** Muti dimensional Sorted Map
*It is indexed by
*It is indexed by
** Row Key:  
** Row Key: Every read or write of data under single row key is atomic. Each row range is called Tablet. Select Row key to get good locality for data access.
Every read or write of data under single row key is atomic.  
** Column Key: Grouped into sets called Column Families. Forms basic unit of Access Control.All data stored is of same type.Syntax used: ''family:qualifier''
Each row range is called Tablet.  
** Time Stamp:Each cell consists of multiple versions of same data which are indexed by Timestamps.In order to avoid collisions, Timestamps need to be generated by applications.
Select Row key to get good locality for data access.
 
** Column Key:  
** Time Stamp


== Dynamo==
== Dynamo==

Revision as of 14:46, 28 March 2015

BigTable

  • Google System used for storing data of various Google Products, for instance Google Analytics, Google Finance, Orkut, Personalized Search, Writely, Google Earth and many more
  • Big table is
    • Sparse
    • Persistant
    • Muti dimensional Sorted Map
  • It is indexed by
    • Row Key: Every read or write of data under single row key is atomic. Each row range is called Tablet. Select Row key to get good locality for data access.
    • Column Key: Grouped into sets called Column Families. Forms basic unit of Access Control.All data stored is of same type.Syntax used: family:qualifier
    • Time Stamp:Each cell consists of multiple versions of same data which are indexed by Timestamps.In order to avoid collisions, Timestamps need to be generated by applications.


Dynamo

  • Availability is the buzz word for Dynamo. Dynamo=Availability
  • Shifted Computer Science paradigm from caring about the consistency to availability.

Cassandra

  • Partitions data across the cluster using consistent hashing.

Spanner

  • Provided data consistency and Supports SQL like Interface