Sunday, May 22, 2011

HEADSTRONG INTERVIEW QUESTIONS

1.How to update records in Target, without using Update Strategy?

YES WITHOUT A pk WE CANT UPDATE THE REC u can write sql query at target
level. in target table properties there is a option update
override.

IN SESSION PROPERTIES WE HAVE ONE OPTION TREAT ALL ROWS
AS... THERE U SELECT UPDATE OPTION AND IN THE TARGET
PROPERTIES SELECT UPDTAE OPTION.

2.Can we lookup a table from source qualifier transformation?
yes we can lookup a table by using S.Q by using sql override.

3.how can we stop batch
By using server manager or pmcmd.

4.Can u start a batches with in a batch?

U can not. If u want to start batch that resides in a batch,create a new independent batch and copy the necessary sessions into the new batch.

5.Can u start a session inside a batch idividually?
We can start our required session only in case of sequential batch.in case of concurrent batch
we cant do like this.
6.how do you connect to remoteserver?
using ftp through telnet/putty/command prompt.
7.What is a command that used to run a batch?
pmcmd is a command line programme. this can be used to stop,run and abort the session.

8.If i done any modifications for my table in back end does it reflect in informatca warehouse or maping desginer or source analyzer?
NO. Informatica is not at all concern with back end database.It displays you all the information  that is to be
stored in repository.If want to reflect back end changes to informatica screens, again you have to import from back end
to informatica by valid connection.And you have to replace the existing files with imported files.

9.How many ways you create ports?
1.Drag the port from another transforamtion
2.Click the add buttion on the ports tab.

10.which is better among incremental load, Normal Load and Bulk load?
It depends on the requirement. Otherwise Incremental load which can be better as it takes only that data which is not available previously on the target.

11.What is the difference between Informatica server, Repository Server and Power center Server ?
Informatica Server and PowerCenter Server both mean the same. It is concerned with running of sessions and workflows.
The Repository Server or the Informatica Rep Server is concerned with connecting to the repository through the Rep Agent.
One Repository Server can connect to many repositories at a time.
For the PowerCenter Server to be up and working it is necessary that the Repository Server is running.

12.in my source table different dateformats i want to load the data into my target single date format how it can be achieved?
by using to_date(datecolumn,'MM/DD/YYYY')

13.while extracting the data from a mainframe sources which transformation should we use?
The mainframe files are Used as VSAM files in Informatica by using the Normaliser transformation

14.i have 7 flatfiles i want to join those files how many joinertransformations required?
6.(n-1)

15.what is pushdownoptimization?
Pushdown optimization is a way of load-balancing among servers in order to achieve optimal performance.
Veteran ETL developers often come across issues when they need to determine the appropriate place to perform ETL logic.
Suppose an ETL logic needs to filter out data based on some condition. One can either do it in database by using WHERE condition
in the SQL query or inside Informatica by using Informatica Filter transformation. Sometimes, we can even "push" some transformation logic
to the target database instead of doing it in the source side (Especially in the case of EL-T rather than ETL).
Such optimization is crucial for overall ETL performance.

16.explain persistance lookupcache?
If the lookup source does not change between sessions, configure the Lookup transformation to use a persistent lookup cache.
The Integration Service then saves and reuses cache files from session to session, eliminating the time required to read the lookup source.

17.i want to send an email, if email task will run only when no data is loaded into the target?
After your session, create an email task. Connect session and email task with the link condition
TgtSuccessRows = 0 and PrevTaskStatus = SUCCEEDED.







2 comments:

  1. Nice one.
    For informatica scenario base questions: informatica scenarios

    ReplyDelete
  2. Hi

    I read this post two times.

    I like it so much, please try to keep posting.

    Let me introduce other material that may be good for our community.

    Source: Target interview questions

    Best regards
    Henry

    ReplyDelete