Question { 10018 }

What is the use of incremental aggregation?

Answer

in incremental aggregation only the captured changes will be
considered for aggregate calculation i.e. when new data will
be inserted for calcutation , informatica power center
server will not start the processing from the begining .

Question { 12808 }

Explain in simple terms, the concept of Data Mining.

Answer

Generally, data mining (sometimes called data or knowledge
discovery) is the process of analyzing data from different
perspectives and summarizing it into useful information -
information that can be used to increase revenue, cuts
costs, or both. Data mining software is one of a number of
analytical tools for analyzing data. It allows users to
analyze data from many different dimensions or angles,
categorize it, and summarize the relationships identified.
Technically, data mining is the process of finding
correlations or patterns among dozens of fields in large
relational databases.

Question { ITC Infotech, 15515 }

surrogate keys usage in Oracle and Informatica?

Answer

surrogate key is one type of key which is used to maintain
history .
it is used in slowly changing dimension (scd)

Question { TCS, 25058 }

Generally how many Fact Tables and Dimensions Table you
have used in the Project?
Which one is loaded first Fact Table or Dimensions Table
into the warehouse?
What is the size of the Fact Table and Dimension Table?
what is the size of the table and warehouse

Answer

it depends upon the requirement of the client . dimension
table is loaded first , using the primary keys of the
dimension table , fact tables are loaded .size of the fact
and dimension table also depends upon the requirement .
size of the table and warehouse also depends upon clients
requirement .

Question { 23133 }

what is difference between

Independent Data Mart Dependent Data Mart
1- 1-
2- 2-
3- 3-
4- 4-

Answer

Independent datamart:it does not get data from datawrehouse
Dependent data mart: It gets data from datawarehouse.

Question { Wipro, 5683 }

I HAVE A FLAT FILE DO THE NULL CHEK AND PRIMARI KEY CHEK
AND DATE VALIDITAION LOAD TO TARGET TABLE

Answer

code should be like this:
Check whether the pk is present, if present, its a duplicate record.
then check for the null values
then check for invalid date columns

iif(not isnull(pk),error_code_dup_rec,
iif(isnull(col1)
or (is null(col2),null_value_
present,
or is null(date),invalid_date,valid_record))

Question { Patni, 9697 }

in flatfile target how can u create header and footer plese
give me the comands how will u write in session properties

Answer

Please be specific about your requirement. what exactly you want to display in header and footer? So that one can provide you the correct solution.

Question { IBM, 18596 }

Why do flat file load is faster if you compare that with
table load ?
Please answer me.

Advance Thanks,
Manojkumar

Answer

One more answer is in general flat files are kept on the server where informatica is installed.Thats the reason flat file loading is faster.

Question { 7879 }

What are the issues that you have faced while moving your
project from the Test Environment to the Production
Environment? Please explain in depth

thanks in advance

Answer

One example can be:

1)missing link between one transformation to the next transformation.

Question { 11181 }

Source having one lakh record and loaded into target. Then, how can i compare records will loaded in table? For example Source having Firstname,Lastname. the same Firstname,Lastname record will be loaded into Target? How can i check in Oracle?

Answer

You can use the minus keyword

Source table name is A
Target table name is B.

Query can be

select * from B
minus
select * from A

or else you can do a minus from A to B.

select * from A
minus
select * from B


Inthis way you can find the mismatch
(Note: This is just one way pf comparing)

Thanks,
Ranjan