Interested to Buy Any Domain ? << Click Here >> for more details...
What is a surrogate key?Why we use it in a mapping?Pl give
an example.
- 4 Answers
- 12242 Views
- PCS, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / saradhi
surrogate key is used to avoid the critical column.critical
column means the column which makes the analysation or data
wrong for example assume one customer table
cust_id(p.k) cust_name amount loc
1 jones 1000 hyd
he purchase the product in hyd by 1000/- if he again
purchase by 2000/- in pune not in hyd.then we have to
create another record in that table with same cust_id but
here cust_id is having primary key so we are unable to
create a new record for suppose if u update the record u
got the wrong information as
1 jones 3000 pune
so eliminating this we are maintian the another column like
cust_no as surrogate key (unique value)and removes p.k in
cust_id.surrogate key is like an index.
| Is This Answer Correct ? | 12 Yes | 1 No |
surrogate key is a System generated Key ( Artificial
key ),Every join between dimension tables and fact tables
in a data warehouse environment should be based on
surrogate keys, not natural keys.
There are still more reasons to use surrogate keys. One of
the most important is the need to encode uncertain
knowledge. You may need to supply a customer key to
represent a transaction, but perhaps you donýt know for
certain who the customer is. This would be a common
occurrence in a retail situation where cash transactions
are anonymous, like most grocery stores.
What is the customer key for the anonymous customer?
Perhaps you have introduced a special key that stands for
this anonymous customer. This is politely referred
to as a "hack."
| Is This Answer Correct ? | 6 Yes | 1 No |
Answer / venkadesh
IT IS UNIQUE KEY AND ITS USED FOR COMPARING THE EMPLOYEE DETAILS
| Is This Answer Correct ? | 0 Yes | 5 No |
Two different admin users created for repository are ______ and_______
Source --------- eno , ename, sal 001,ank,1000 002,behe,2000 003,raj,2500 Target ------- header :DDMMYYYY24MMSS timestamp body: 001,ank,1000 002,behe,2000 003,raj,2500 footer: count(eno),sum(sal) how to implement the same in a FF tgt?
What is an aggregator transformation?
Explain Dataware house architecture .how data flow from intial to end?
can we override a native sql query within informatica? How do we do it?
in which situations do u go for scds ?
What are reusable transformations in how many ways we can create them?
Explain is there any way to read the ms excel datas directly into informatica? Like is there any possibilities to take excel file as target?
How do you load more than 1 max sal in each department through informatica or write sql query in oracle?
Explain in detail about scd type 1 through mapping.
What is an unconnected transformation?
In my sourse i have like ename,gender vasu,male geetha,female ram,male suma.female kesav,male in my output i need male,female vasu,geetha ram,suma kesav
Teradata 
