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Surrogate Key
Why do we use Surrogate Key?


  
Total Answers and Comments: 2 Last Update: July 01, 2009     Asked by: mitul arora 
  
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November 17, 2008 17:38:50   #1  
developer_veni Member Since: October 2008   Contribution: 12    

RE: Surrogate Key
Surrogate key:

It is the system generated key which cannot be edited by the user.
It is the primary key of the dimension table in warehouse.
It is nothing but the sequence which generates the numbers for primary key column.

 
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July 01, 2009 06:56:40   #2  
Simba123 Member Since: July 2009   Contribution: 1    

RE: Surrogate Key
Surrogate keys are system generated keys. They are integers.

Surrogate keys are extremely useful when having type 2 data ( i.e. storing historical information)
For ex: Consider one has a table in which a person and his location are stored. Now when his location is changed and we want to keep a historical record of the same it is stored with a surrogate key that will help us to uniquely identify the record.

This is also a reason that OLTP keys are not used in the warehouse and a seperate dimension or surrogate key is maintained.

 
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Read Answers (3) | Asked by : vasanth kishore

Latest Answer : Surrogate keys are the system generated keys and used to eliminate the redundancy in the primary keys. So they are always integer numbers. ...
Read Answers (5) | Asked by : pepsi

Why do we use Surrogate Key? 
Latest Answer : Surrogate keys are system generated keys. They are integers.Surrogate keys are extremely useful when having type 2 data ( i.e. storing historical information)For ex: Consider one has a table in which a person and his location are stored. Now when his ...


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