Surrogate Key is a Primary Key for a Dimension table. Most importance of using it is it is independent of underlying database. i.e Surrogate Key is not affected by the changes going on with a database.
RE: Importance of Surrogate Key in Data warehousing?
The concept of surrogate comes into play when there is slowely changing dimension in a table. In such condition there is a need of a key by which we can identify the changes made in the dimensions. These slowely changing dimensions can be of three type namely SCD1,SCD2,SCD3.
These are sustem genereated key.Mainly they are just the sequence of numbers or can be alfanumeric values also.
RE: Importance of Surrogate Key in Data warehousing?&n...
I slightly differ from the reply posted by Mr. Abhishek
Surrogate Key should be system generated number and it should be small integer. For each dimension table depending on the SCD and no of total records expected over a 4 years time, you may limit the max number. This will improve the indexing, performance, query processing.
RE: Importance of Surrogate Key in Data warehousing?&n...
surrogate is the systemgenerated key it is a numaric key it is primary key in the dimension table and it is forgien key in the fact table it is used to hadle the missing data and complex situation in the datastage
