20 Datastage Interview Questions for Experienced PDF Download

Datastage Interview Questions for Experienced PDF Download

1) What is Datastage ?

• Design jobs for Extraction, Transformation and Loading(ETL).
• Ideal tool data integration projects such as data warehouses, data marts and system migrations
• import, export, create and managed metadata for use within jobs.
• Schedule, run and monitor jobs all withinDatastge
• Adminsters your Datastage development and execution environments.

2)   How did you handle reject data?
Typically a Reject-link is defined and the rejected data is loaded back into data warehouse. So Reject link has to be defined every Output link you wish to collect rejected data. Rejected data is typically bad data like duplicates of Primary keys or null-rows where data is expected.


3)  If worked with DS6.0 and latest versions what are Link-Partitioner and Link-Collector used for?

Link Partitioner – Used for partitioning the data.
Link Collector – Used for collecting the partitioned data.[sociallocker]

4) What are OConv () and Iconv () functions and where are they used?


IConv() – Converts a string to an internal storage format

OConv() – Converts an expression to an output format.

5) What are Routines and where/how are they written and have you written any routines before?

Routines are stored in the Routines branch of the DataStage Repository, where you can create, view or edit. The following are different types of routines:


1) Transform functions


2) Before-after job subroutines


3) Job Control routines

6) How did you connect to DB2 in your last project?

Using DB2 ODBC drivers.

7)  Explain METASTAGE?

MetaStage is used to handle the Metadata which will be very useful for data lineage and data analysis later on. Meta Data defines the type of data we are handling. This Data Definitions are stored in repository and can be accessed with the use of MetaStage.

8) How do you merge two files in DS?

Either use Copy command as a Before-job subroutine if the metadata of the 2 files are same or create a job to concatenate the 2 files into one if the metadata is different.

9) Do you know about INTEGRITY/QUALITY stage?

Qulaity Stage can be integrated with DataStage, In Quality Stage we have many stages like investigate, match, survivorship like that so that we can do the Quality related works and we can integrate with datastage we need Quality stage plugin to achieve the task.

10) Explain the differences between Oracle8i/9i?

Oracle 8i does not support pseudo column sysdate but 9i supports
Oracle 8i we can create 256 columns in a table but in 9i we can upto 1000 columns(fields)

11) Question.10 What is DS Designer used for?

You use the Designer to build jobs by creating a visual design that models the flow and transformation of data from the data source through to the target warehouse. The Designer graphical interface lets you select stage icons, drop them onto the Designer work area, and add links.

12) What are conformed dimensions?

A conformed dimension is a single, coherent view of the same piece of data throughout the organization. The same dimension is used in all subsequent star schemas defined. This enables reporting across the complete data warehouse in a simple format.

13)Why fact table is in normal form?

Basically the fact table consists of the Index keys of the dimension/ook up tables and the measures. so when ever we have the keys in a table .that itself implies that the table is in the normal form.

14)What is DS Administrator used for?

The Administrator enables you to set up DataStage users, control the purging of the Repository, and, if National Language Support (NLS) is enabled, install and manage maps and locales.

15)What is DS Director used for?

datastage director is used to run the jobs and validate the jobs.we can go to datastage director from datastage designer it self.

16)What is DS Manager used for?
The Manager is a graphical tool that enables you to view and manage the contents of the DataStage Repository.

17)What is a linked cube?

A cube can be stored on a single analysis server and then defined as a linked cube on other Analysis servers. End users connected to any of these analysis servers can then access the cube. This arrangement avoids the more costly alternative of storing and maintaining copies of a cube on multiple analysis servers. linked cubes can be connected using TCP/IP or HTTP. To end users a linked cube looks like a regular cube.

18)What are Static Hash files and Dynamic Hash files?
As the names itself suggest what they mean. In general we use Type-30 dynamic Hash files. The Data file has a default size of 2Gb and the overflow file is used if the data exceeds the 2GB size.

19)What is Hash file stage and what is it used for?

Used for Look-ups. It is like a reference table. It is also used in-place of ODBC, OCI tables for better performance.

20)How are the Dimension tables designed?

Find where data for this dimension are located. Figure out how to extract this data. Determine how to maintain changes to this dimension.Change fact table and DW population routines.


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10 DataStage Interview Questions and Answers - Download PDF

10 DataStage Interview Questions and Answers

1) What is Datastage ?
2) What are the differences between Datastage and Informatica
3) How do you generate Sequence number in Datastage?
4) What are the components of DataStage?
5) What is a merge in DataStage?
6) What are system variables and sequencers in DataStage
7) What is the difference between operational data stage (ODS) and data warehouse?
8) Purpose of Pivot Stage and types of containers in DataStage
9) What can we do with DataStage Director?
10) What is the difference between data warehousing and OLAP?

1) What is Datastage ?

• Design jobs for Extraction, Transformation and Loading(ETL).
• Ideal tool data integration projects such as data warehouses, data marts and system migrations
• import, export, create and managed metadata for use within jobs.
• Schedule, run and monitor jobs all withinDatastge
• Adminsters your Datastage development and execution environments.

2) What are the differences between Datastage and Informatica

• Data stage supports parallel processing
• Links are treated as objects in Data Stage
• Links are port to port connectivity in Informatica
• The implementation of Slowly Changing Dimensions is easy in Informatica which are complex in Data Stage
• Complete error handling is not supported by informatica, which is supported Datastage.

3) How do you generate Sequence number in Datastage?

Sequence numbers can be generated in Datastage using certain routines. They are

• KeyMgtGetNextVal
• KeyMgtGetNextValConn

4) What are the components of DataStage?

Datastage has two components

• Client Components – Designer, Director, Manager and Administrator
• Server Components – Server, Repository and Plug-ins.

5) What is a merge in DataStage?

Merge in DataStage :

• is available in both parallel an server jobs as a specific stage
• is used for the purpose of joining two tables such as server/parallel or tables/datasets
• is done on a key field which is mandatory in both master and update dataset

6) What are system variables and sequencers in DataStage

 System variables:

• System variables are used to get system information
• They are accessed by a transformer or by a routine
• They have @ as prefix and are read only

Sequencers:

• Sequencers allows for synchronizing the control flow of various activities in a single sequence of jobs.
• The number of input and output triggers can be multiple

7) What is the difference between operational data stage (ODS) and data warehouse?

Data warehouse

• It is a decision support database system for the purpose of organizational needs. 
• It is non volatile, integrated and time variant collection of data

Operational Data Source

• It is an integrated collection of information. 
• It can contain 90 days of information at maximum.
• ODS supports dynamic data.

8) Purpose of Pivot Stage and types of containers in DataStage

What is the purpose of Pivot Stage?

Pivot Stage is used to convert columns to rows

What are the types of Containers?

There are two types of containers namely, Local Container and Shared Container

9) What can we do with DataStage Director?

• Validating
• Scheduling
• Executing
• Monitoring server jobs

10) What is the difference between data warehousing and OLAP?

• Data warehouse refers to organization and data storage from various resources
• Data warehousing is used for data analysis. 
• OLAP is to deal with data analysis with a software 
• OLAP is used for managing aggregations and information partition for in-depth analysis
• Business intelligence is performed with OLAP.

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10 Javascript Questions And Answers For Fresher And Experienced

Javascript Questions And Answers For Fresher And Experienced

What is HTML ?

HyperText Markup Language, commonly referred to as HTML, is the standard markup language used to create web pages. Along with CSS, and JavaScript, HTML is a cornerstone technology, used by most websites to create visually engaging webpages, user interfaces for web applications, and user interfaces for many mobile applications.Web browsers can read HTML files and render them into visible or audible web pages. HTML describes the structure of a website semantically along with cues for presentation, making it a markup language, rather than a programming language.


What is javascript ?

JavaScript is a lightweight, interpreted programming language. It is designed for creating network-centric applications. It is complimentary to and integrated with Java. JavaScript is very easy to implement because it is integrated with HTML. It is open and cross-platform.



Question: How to pass multiple parameter in setTimeout function?

function myFunctionName(var1,var2){
    console.log('called after 2 sec of page load '+var1+' '+var2);
}
setTimeout(myFunctionName,2000,'value1','value2');

Question: How to enumerate the properties of js objects?

var myObject = {name1: 'Value1',name2: 'Value2'};
//console.log(myObject); //It will print all the values

for (var name in myObject) {
  //console.log(name+'=>'+myObject[name]);
  }

Question: How to measure the execution time of javascript script?

var startTime = new Date().getTime();
/*
Write here you script
*/
for(i=1;i<=500000; i++){
}
var endTime = new Date().getTime();

var time = endTime - startTime;
console.log('Execution time in Milli Seconds: ' + time);
console.log('Execution time in Seconds: ' + time/1000);

Question: How to listen (Do some changes) the window.location.hash change?

$(window).on('hashchange', function() {  
  callNewFunction(window.location.href)  
});
function callNewFunction(url){
    console.log('Hash URL is called');
}

After appling above code, whenever you add/update the hash value, callNewFunction will called automatically.

hashchange event is HTML5 feature and supported by all modern browsers and support is added in following browser.

1. Internet Explorer 8
2. Firefox 3.6
3. Chrome 5
4. Safari 5
5. Opera 10.6

Question: How to add class in an element?
HTML Part

javaScript Part

var d = document.getElementById("myDivId");
d.className += " newClass";

Question: How to get the list of classes for an element?

d = document.getElementById("myDivId");
console.log(d.className);

Question: Can we compare two javaScript objects?
Yes, We can compare two javascript objects. See Following examples.

var myObject1 = {name1: 'Value1',name2: 'Value2'};
var myObject2 = {name1: 'Value111',name2: 'Value222'};
if(JSON.stringify(myObject1) === JSON.stringify(myObject2)){
 console.log("Both object are same");
}else{
console.log("Both object are different");
} 

Question: What is difference between Array(3) and Array('3') in javascript?
new Array(3), means declare the 3 elements and each have value "undefined". new Array('3'), means declare the 1 element and have value 3.

console.log(new Array(3)); // [undefined, undefined, undefined]
console.log(new Array('3')); // ["3"]

Question: How to get browser URL for all browser?

console.log(window.location.href);

Question: How to remove an element(string OR object ) from javascript Array/Object?

var myObject = {name1: 'Value1',name2: 'Value2'};
delete myObject['name1']
console.log(myObject);

Question: What does jQuery.fn mean?
jQuery.fn is just an prototype for defining the new functions.
fn is an alias to the prototype property.
For Example,

$.fn.newFunctionName = function(val){
console.log('something '+val); //something Test Value
};
$.fn.newFunctionName('Test Value');

Question: How to remove an empty elements from an Array?

var simpleArray = [1,3,,3,null,,0,,undefined,4,,6,,];
var cleanArray = simpleArray.filter(function(n){ return n != undefined }); 
console.log(cleanArray);

Question: How to add 5 days in JavaScript?

var result = new Date();
result.setDate(result.getDate() + 5);
console.log(result);

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