what is surrogatekey ? In ur project in which situation u
has used ? explain with example ?
Answer Posted / murali
the surrogate key is the primary key used to avoid the
problem of critical column. let me clarify u with example...
table A:
Cust_no(PK) Cust_name Loc
100 X Mumbai
this is what ur OLAP DHW is having abt Customer X
But, he has changed his address from X to Y. U have to
update this in ur OLAP DWH. then, i u try to insert this
into ur Table A,
Error: Prinary key Constraint violated (Coz,PK is same for
the both the records)... then, LOC is the Critical Column.
to avoid this, we need to generate a primary key either by
user defined or system generated.
| Is This Answer Correct ? | 11 Yes | 0 No |
Post New Answer View All Answers
What are the different clients of powercenter?
Why do we need informatica?
What is the difference between power center and power mart? What is the procedure for creating independent data marts from informatica 7.1?
Which is the t/r that builts only single cache memory?
What is joiner change?
tell me about your project functionality
Hi Everybody, I have one fixed width file as source and 4 oracle tables (relational) as target. What are the Unit test cases i need to implement ? 1.Using TextPad software i tested postion of the field 2.As per specification i tested like whether it is correctly mapped or not? Is there any other test case do i need to implement. If possible can any one give me the test cases Advance Thanks
Briefly explain your complete project(sales) flow, (ie. from source received from client, transformations, then despatch to end user) what are all the process. Kindly give step by step process.
How to convert a row into column and a column into rows? Name all DTM threads. What all threads stop when we issue STOP or ABORT? How to pass the value of a data(variable kind of) from one session ( generated in mapping) to another session in the same workflow... What are the tyoes of partitioning you know and how to apply them in real time ... Can partitioning be applied to expression transformation and how
How to generate sequence numbers?
If informatica has its scheduler why using third party scheduler?
Which transformation should we use to normalise the COBOL and relational sources?
How to improve the performance of a session using sorter transformation?
Explain the difference between mapping parameter and mapping variable?
What is meant by lookup transformation?