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Top Informatica Questions Asked In Interviews

Hi Folks , from this post onwards we will be posting some Top Informatica Questions that are generally being asked in Interviews.

1. How do u change parameter when u move it from development to production. ?
2. How does the session recovery work. ?
3. why use shortcuts(Instead of making copies). ?
4. where is the reject loader and how to use it. ?
5. Do you have to change the reject file before using reject
loader utility. ?
6. Differences between current and previous versions. ?
7. Debugger – what are the modules, what are the options
you can specify when using debugger, can you change the
expression condition dynamically when the debugger is running ?
8. Mapplets – can you use an active transformation in a Mapplet ?
9. What are active transformations?
10. Can u use flat files in Mapplets ?
11. How many transformations can be used in mapplets. Is there any specified limit ?
12. Can a joiner be used in a mapplet?
13. How can you join 3 tables? Why cant you use a single Joiner to join 3 tables
14. Global and Local shortcuts. Advantages.
15. Mapping variables, parameters syntax, if you create mapping variables
and parameters in mapplet can u use them in the mapping?
16. Have you worked with/created Parameter file
17. What’s the layout of parameter file (what does a parameter file contain?)?
18. Why do we use Mapping Parameter and mapping variable?
19. Session Recovery. 1000 rows in the source of which 500 passed
through and then I killed the session. Can you perform a recovery and how ?
20. What are the modules in Power Center ?
21. filter transformation in the condition one of the data is NULL would the record be dropped.?
22. Implement all three SCD’s using Informatica and with different approaches. ?
Please Leave your comment if you have any query
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Top 10 Medium Level SQL Interview Question And Answers


These are some of the Top 10 Medium SQL Interview Question And Answers That A 1 Year Exp person should know.

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1) Write SQL Query to find details of employee with second highest salary of Employee table
2) SQL Query to find Max Salary from each department.
3) Write SQL Query to display current date.
4) Write an SQL Query to check whether date passed to Query is date of given format or not.
5)  Write a SQL Query to print the name of distinct employee whose DOB is between 01/01/1960 to 31/12/1975.
6) Write an SQL Query find number of employees according to gender  whose DOB is between 01/01/1960 to 31/12/1975.
7)Write an SQL Query to find employee whose Salary is equal or greater than 10000.
8)Write an SQL Query to find name of employee whose name Start with ‘M’
9) find all Employee records containing the word "Joe", regardless of whether it was stored as JOE, Joe, or joe.
10) Write a SQL Query to find  year from date.

Check this post on Top 13 Sql Interview Questions And Answers

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Top 13 SQL Interview Questions And Answers


Welcome to our Top 13 SQL Interview Questions and Answers page, we  start with basic questions, move on to intermediate level and finish on advanced questions.

NOTE: If you would like to focus on basic SQL interview questions only then we recommend visiting our Basic Interview Q&As page.

we will be uploading a pdf very soon for the post sql interview questions and answers , one should give when appearing for an interview. kindly subscribe to grab your copy.

Questions are split into 3 levels :-

Questions For Fresher’s:

Question 1: What type of joins have you used? 
Question 2: How can you combine two tables/views together? For instance one table contains 100 rows and the other one contains 200 rows, have exactly the same fields and you want to show a query with all data (300 rows). This sql interview question can get complicated. 
Question 3: What is the difference between where and having clause? 
Question 4: How would apply date range filter? 
Question 5: What type of wildcards have you used? This is usually one of mandatory sql interview question. 
Question 6: How do you find orphans? 
Question 7: How would you solve the following sql queries using today's date: First day of previous month, First day of current month, Last day of previous month, Last day of current month?

Questions For Experienced:

Question 8: You have a table that records website traffic. The table contains website name (multiple websites), page name, IP address and UTC date time. What would be the query to show all websites visited in the last 30 days with total number or visits, total number if unique page view and total number of unique visitors (using IP Address)? 
Question 9: How to display top 5 employees with the higest number of sales (total) and display position as a field. Note that if both of employees have the same total sales values they should receive the same position, in other words Top 5 employees might return more than 5 employees.

Advanced Questions:

Question 10: How to get accurate age of an employee using SQL? 
Question 11: This is SQL Server interview question. You have three fields ID, Date and Total. Your table contains multiple rows for the same day which is valid data however for reporting purpose you need to show only one row per day. The row with the highest ID per day should be returned the rest should be hidden from users (not returned). 
Question 12: How to return truly random data from a table? Let say top 100 random rows? 
Question 13: How to create recursive query in SQL Server?

Check this post on Top Medium Level Interview Question And Answers

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Clover ETL

clover etl

We are living in exciting times in the field of data integration , tools like Talend , Pentaho are giving heavyweight tools Informatica ,Ablnitio and Datastage a run for their money . The features offered by these tools though not as matured as the bigger heavy weight tools , but are exhaustive nonetheless (especially the features offered by Talend) . Today we are discussing another such tool , Clover ETL .

Clover Overview

Clover Data Integration is relatively new compared to their competitors Talend , Pentaho . Like Talend , Clover uses the Eclipse framework for the visual editor and use JRE to run transformations the difference being Clover is a metadata driven tool and does not need code generation to run jobs.

CloverETL has a smaller pallete but offers functionality which is much complex.They are easier to choose from with well defined functionality.But features like parallelism is supported in the enterprise version , which seems to be a trend in all these “opensource data integration” tools.


  • Pass parameter to Graphs through file.
  • Enables visual debugging and data monitoring at any point of time.
  • Easy switch between graphs.
  • Share connections between data structures.


Input and Output Components:










Transformations Provided:














Types of Joins Provided:

CloverETL- Joiners







If you would like to learn more about this awesome tool , access the following link :CloverETL


Clover ETL shows a lot of promise and is a very powerful tool in its own right. Provided this article just provide an overview of the tool , you can expect more articles in the future to have a detailed Talend v/s CloverETL analysis. Given the economic slowdown where bootstrapping is a necessity , CloverETL along with other tools like Talend and Pentaho are reliable , powerful options to consider !!

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Inheritance in Object-oriented Programming

Inheritance in Object-oriented Programming

Inheritance in Object-oriented Programming is an important concept. Inheritance defines the relationship between the different objects.

Inheritance is the process wherein characteristics are inherited from ancestors. Similarly, in Java, a subclass inherits the characteristics (properties and methods) of its superclass (ancestor).

An object is able is able to inherit characteristics from another object. In other words we can say that an object is able to pass on its state and behavior to its children. The objects need to have characteristics in common with each other for inheritance to work.

For example Mountain bikes, road bikes, tandem bikes, all share common characteristics of bikes like speed, gear. Also all these bikes have some additional functionalities.

Inheritance in Object-oriented Programming allows classes of mountain bike, road bike, tandem bike to having the properties of class bike and bike became the superclass of all the type of bikes. In Java Programming language each subclass can have one direct superclass and superclass can have unlimited number of subclass.

Inheritance in Object-oriented Programming

Inheritance in Object-oriented Programming


One Liner: Inheritance is a mechanism wherein a new class is derived from an existing class.

In Java, classes can inherit or we can say acquire the properties and methods of other classes. A class that inherits from another class is called a subclass, whereas the class from which a subclass is derived is called a superclass. The keyword “extends” is used to derive a subclass from the superclass.

There is simple syntax for creating a subclass. Use the extend keyword at the beginning of your class declaration, followed by the name of the class to inherit from (superclass):

class MountainBike extends Bike {


   // new fields and methods defining

   // a mountain bike would go here



This gives Mountain Bike all the same fields and methods as Bike, yet allows its code to focus exclusively on the features that make it unique.

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Interface in Object-oriented Programming

Interface in Object-oriented Programming

Objects interact with outside word through the methods that they exposed.

So Interface can be defined as contract which has enlisted all the methods which must be supported by the objects.

One Liner: An Interface in Object-oriented Programming is a blueprint of a class. It has static constants and abstract methods.

The interface is a mechanism to achieve fully abstraction in java. There can be only abstract methods in the interface. It is used to achieve fully abstraction and multiple inheritances in Java.

Consider ‘receive’ and ‘reject’ buttons on your phone. You know that these buttons will receive and reject the call and must support by the phone that’s why they are in the phone. The buttons acts as interface between you and phone.

Interface Phone {

Void receives ()

Void reject ();


Interfaces cannot be instantiated, but rather are implemented.Implementing an interface allows a class to become more formal about the behavior it promises to provide. Interfaces form a contract between the class and the outside world, and this contract is enforced at build time by the compiler. If your class claims to implement an interface, all methods defined by that interface must appear in its source code before the class will successfully compile.

In Java IS-A relationship is represented by interface.

Interface in Object-oriented Programming

Interface in Object-oriented Programming


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Class in Object-oriented Programming

Class in Object-oriented Programming

Class in object-oriented programming, a class is an extensible program-code-template for creating objects, providing initial values for state (member variables) and implementations of behavior (member functions, methods).


One Liner: A Class in Object-oriented Programming is an expanded concept of a data structure: instead of holding only data, it can hold both data and functions.

A class is a blueprint or template or set of instructions to build a specific type of object. Every object is built from a class.

Class in Object-oriented Programming

Class in Object-oriented Programming

Let’s try to understand the class with the example of making cookies.

Class is like recipe of how to make cookie. The recipe itself is not a cookie. You can’t eat the recipe. If you follow the recipe then you can make cookie. The cookie which we made from the recipe can be referred as an object.

You can make as many cookies as you would like using the same recipe. Similarly you can create as many instances of a class as you would like.

Now assume that you have to create cookies for different people. How you will identify which cookie is for which person. A simple solution is that write name of the person on the cookie. Reference variables work in similar fashion. A reference variable provides a unique name for each instance of a class. In order to work with a particular instance, you use the reference variable it is assigned to.

Creating class Cookie:

Class Cookie {

String flavor;

String taste;



Creating cookies for different persons:

Cookie cookieForPerson1 = new Cookie ();

Cookie cookieForPerson2 = new Cookie ();



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