Unix Interview Questions (Part1)

Following are some unix commonly asked interview questions  Q 1  What is command to check space in Unix Ans : df -k Q 2 If a file has permission 000 then who can access the File Ans : System Administrator .Q 3 What is command to kill last background Job Ans : kill $!Q 4 How you will list all Hidden files Ans : ls -la|grep ^[.] Q 5 What is command to create Zero Byte File Ans : touch filename Q 6  What is difference between diff and cmp command Ans : cmp -It compares...

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Informatica Metadata Queries (Part1)

Informatica Metadata QueriesIn Informatica normally we come across situation like we need to find all mapping which use a particular table as source or something similar .It is very difficult to find it through Informatica tools.In such a situation Repository tables are very useful.Repository tables name start with OPB and are continuously updated when we make changes.Along with OPB tables REP views are also present.It is very dangerous to modify these tables so due care should be taken while dealing with OPB Tables.In this article we will...

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Oracle Deferred Constraints

Oracle Deferred Constraints :Recently we came across a unique situation of updating a primary key of master table which being referenced by child table.Problem with updating primary key of master table was that it would have made child table orphan (ora-02292 child found)and we could not even update child table as it would have violated referential integrity.To overcome this we used the deferrable constraint introduced by oracle.A deferrable constraint is only checked at transaction commit time.We altered the foreign key on child table to make...

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Informatica interview questions (Part 3)

We will continue with third set of questionsQ 1 What is the use of Shared Folder?Ans : Shared folders allow users to create shortcuts to objects in the folder.If you have an object that you want to use in several mappings or across multiple folders, we can place the object in a shared folder.we can then access the object from other folders by creating a shortcut to the object. Shortcuts inherit changes to their shared object. Shared folders in global repositories can be used by any folder in the domainOnce you make a folder shared, you cannot...

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Kimball Vs inmon

There are two major design methodologies followed in data warehousing Ralph Kimball and Bill Inmon.We will discuss about both of these in detail.Bill Inmon Approach : According to Bill Inmon Data warehouse need to fulfill need of all category of users .In an organization there are different type of user like· Marketing· Supply Change Management· OperationsEach department has its different way of interpreting data so Data warehouse should be able...

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Best Practices in Informatica (Part1)

We have tried to come up with some of best practices in informatica1) Always try to add expression transformation after source qualifier and before Target. If source or target definition changes it is easier to reconnect the ports2) Always use Cobol File for normaliser in binary format otherwise there are lot of issues specially with comp-3 fields3) Remove unused ports, though unused ports do not have any effect on performance bit it is always better to remove them for more visibility4) If possible try to do calculation in Output Ports instead...

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Unix Script to Automate FTP Process

Unix Script to Automate FTP ProcessNormally we come across the situation when we have to FTP file daily.Doing this process daily for large no of files can be cumbersome.We can create Unix script to automate FTP ProcessCurrently we need to last day files from production to dev box for testing,so we created below mentioned script to FTP files dailyb=`TZ=CST+24 date +%y%m%d` ###To get last datecd /export/home/mydirftp -v -n FTP_HOST_NAME EOF ##Please put two less than sign before EOF user Userid Pwdbincd /export/home/source_dirget FILE_NAME.`echo...

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