Top JavaScript Interview Questions With Answers

JavaScript one of the most popular programming language among web developers. Its a broswer based coding for client side operations. For fast form validations.PHP , Dotnet, java like programming languages are used fro server side coding. Javascript can handle many operations like form field validations, file operations, send requests to server using Ajax, Curl like methods etc. Here I have collected 20 Javascript interview questions that will be asked commonly in interviews. On the last page I have added a PDF version for quick reference. I have just added the questions only and you should prepare the answers before attending the interviews.

JavaScript

JavaScript is dynamic, high-level, untyped and interpreted language used in programming on the web. It is popular and powerful programming language on the web. JavaScript is used by the majority of websites and it is supported by modern browsers without having to make use of plug-ins.

It is prototype-based, with first class functions, which makes it a multi-paradigm language able to support imperative, object-oriented and functional styles of programming. It is standardized in the ECMAScript language specification.

JavaScript interview questions with answers

Here are a few JavaScript interview questions you are likely to come across and the answers to the questions:

  1. What are JavaScript types?

Ans:

Here are the JavaScript types

  • Number
  • Object
  • String
  • Boolean
  • Function
  • Null
  • Undefined
  1. What is negative infinity?

Ans:

Negative infinity is a number which you can get in JavaScript by dividing negative number by zero.

  1. What is the difference between ViewState and SessionState?

Ans:

ViewState is specific to a page in session.

SessionState relates to user specific data which one can access across all pages in the web application.

  1. Does JavaScript support automatic type conversion?

Ans:

Yes. JavaScript supports automatic type conversion. It is mostly used by JavaScript developers as their common way of type conversion.

 

  1. What is the significance of, and reason for, wrapping the entire content of a JavaScript source file in a function block?

Ans:

It is a common practice which many famous JavaScript libraries (jQuery, Node.js, etc) make use of. The technique produces a closing around the whole file’s content, which generates a private namespace, thereby assisting in preventing clash of name between different JavaScript modules and libraries.

 

  1. What would be the output of the code below?

console.log(0.1+0.2);

console.log(0.1+0.2==0.3);

Ans:

An informed answer to this question would rightly be: “You can’t be sure. It is possible to print out ‘0.3’ and ‘true’, or it might just not. In JavaScript, numbers are treated with floating point precision, therefore, may not always give you the result you expect”.

The above example is classic case which demonstrates this issue. Shockingly, this is what it will print out:

0.30000000000000004

false

  1. Write a simple function (less than 80 characters) that returns a Boolean indicating whether or not a string is a palindrome.

Ans:

The following one line will return ‘true’ if str is a palindrome; otherwise, it returns false.

function isPalindrome(str) {

str = str.replace(/\w/g, ”) .toLowerCase();

return (str == str.split(”) .reverse() .join(”));

}

For instance:

console.log(isPalindrome(“level”));                                // logs ‘true’

console.log(ispalindrome(“level”));                                // logs ‘false’

console.log(isPalindrome(“A car, a man, a maraca”));  // logs ‘true’

 

  1. What will the following code output to the console? Please, explain your answer.

console.log((function f(n){return ((n > 1) ? n * f(n-1) : n)})(10));

Ans:

The code will output the value of 10 factorial (i.e., 10!, or 3,628,800).

This is the reason:

The named function f() recursively calls itsefl, until it gets down to calling f(1) which then returns 1. So, here is what this does:

f(1): returns n, which is 1

f(2): returns 2 * f(1), which is 2

f(3): returns 3 * f(2), which is 6

f(4): returns 4 * f(3), which is 24

f(5): returns 5 * f(4), which is 120

f(6): returns 6 * f(5), which is 720

f(7): returns 7 * f(6), which is 5040

f(8): returns 8 * f(7), which is 40320

f(9): returns 9 * f(8), which is 362880

f(10): returns 10 * f(9), which is 3628800

  1. What do you mean by NULL in JavaScript?

Ans:

NULL represents no value or no object. It simply means no object or null string, no array object, no number and no valid Boolean value.

  1. What are all the types of Pop up boxes available in JavaScript?

Ans:

They include

  • Alert
  • Confirm, and
  • Prompt
  1. You can expect some basic questions like what is Javascript and its difference form other languages like Java
    2_What is JavaScript
  2. 3_difference between JavaScript and java
  3. 4_difference between JavaScript and jscript
  4. Prepare the array operations with Javascript
    5_How to create arrays in JavaScript
  5. 6_What are JavaScript types
  6. 7_How to call external JavaScript file
  7. 8_What is BOM and DOM
  8. 9_What is negative infinity
  9. It will be a sure question about file operations in Javascript
    10_How to read and write a file using javascript

Top Python Programming Interview Questions with Answers

Python is one of the most readable high level programming language. It is widely used by the companies like Google. Its expresions are very much similar like C & Java programming. Here I have collected some Python interview questions which are generally asked for your Python related jobs interview.You can also download 35 Python interview questions in PDF format.

About Python

Python is a high-level programming language that is widely used for programming on a general purpose level. It features a dynamic type system and automatic memory management, with the ability to sustain multiple programming models, which include imperative, object-oriented, functional programming and procedural styles. Python was built by Guido van Rossum and made available for use in 1991.

Python is quite popular and it has interpreters for several operating systems, giving room for its code to run on a broad diversity of systems. It comes with a big and complete standard library. The reference implementation of Python (CPtython) is open source software and it is handled by the Python Software Foundation (a Non-Profit Organization).

Python interview questions and answers

Here are a few Python interview questions and answers

  1. What is PEP8?

Ans.

This is a coding convention, a set of recommendation, on how best to write Python code and improve its readability.

  1. How do we interpret Python?

Ans.

Python language is an interpreted language. The program runs directly from the source code and converts the source code that the programmer writes into an immediate language that is then translated into a language that needs to be executed by a machine.

  1. What is a Python decorator?

Ans.

A Python decorator is a specific change that is made in Python syntax to effortlessly modify functions.

  1. What is the difference between list and tuple?

Ans.

While list is mutable, tuple is not. One can hash tuple, for instance, as a key for dictionaries.

  1. What are Dict and List Comprehensions?

Ans.

These are syntax constructions that help to simplify the creation of a dictionary or list based on iterable that already exists.

  1. What is Lambda in Python?

Ans.

Lambda is a single expression anonymous function that is mostly used as inline function.

  1. What are iterators?

Ans.

Iterators are used for iterating a group of elements, containers like list.

  1. What is slicing?

Ans.

Slicing is a mechanism that helps you in selecting a range of items from sequence types such as tuple, string, list, etc.

  1. What is docstring?

Ans.

Docstring is another name for a Python documentation string. It is way to document Python modules, classes and functions.

  1. What is pass in Python?

Ans.

Pass simply stands for, no-operation Python statement. It is a place holder in compound statement, where a blank should be left, with nothing written there.

  1. Why do lambda forms in Python not have statements?

Ans.

A lambda form does not have statements since it is used in making new function object and returning them at runtime.

  1. What is unittest?

Ans.

Unittest is the unit testing framework in Python. It aids in automation testing, sharing of setups, aggregation of tests into collections, shutdown code tests, etc.

  1. What is the difference between Xrange and range?

Ans.

While Xrange returns xrange objects, range on the other hand, returns the list and makes use of the same memory irrespective of the range size.

  1. How do you delete a file in Python?

Ans.

You simply make use of the command os.remove (filename) or os.unlink (filename)

  1. What is the use of the split function in Python?

Ans.

The split function in Python helps in breaking a string into shorter strings by using the defined separator. It provides a list of the words contained in the string.

I have just added the questions only ( not their answers ) for a quick reference. You can find the relevant answers from other tutorials available on the net by searching. Make sure prepare the answers for all of these questions added here.

  1. 36_What are iterators in Python
  2. 2_What is module in python
  3. 3_Explain how python is interpreted
  4. 4_What is the method does join() in python belong to
  5. You can expect a sure question relating Local & Global variables
    5_What are the rules for local and global variables in Python
  6. 6_What is package in python
  7. 7_What is slicing in Python
  8. Make sure to prepare about the features of Python like Memory Management
    8_How is memory managed in Python
  9. 9_Explain the dictionary in Python
  10. 10_How do we share global variables across modules in Python
  11. 11_What is namespace in python
  12. Learn about the advanatges & disadvantages of Python compared to other programming languages
    12_Phyton Advantages and Dis-Advantages

Ab Initio interview questions with answers

Ab Initio is an American based company and their products focused on data processing with an easy to use user interface.Ab Initio is a multinational enterprise software corporation that is located in Lexington, Massachusetts, USA. The company’s main area of specialization is integration of enterprise application and applications for processing of high-volume data. The company was founded by Sheryl Handler (the former CEO of Thinking Machines Corporation) and several former employees, in 1995 after the company went bankrupt.

The applications execute functions that are related to the analysis of fourth generation data, processing of batch, manipulation of data, graphical user interface (GUI)-based parallel processing software which is often used for extracting, transforming and loading data.

The list of their products

  • Graphical Development Environment (GDE)
  • Business Rules Environment (BRE)
  • Enterprise Meta>Environment (EME)
  • Co>Operating System
  • Conduct>It
  • Data Profiler
  • the Component Library

Here I have collected some commonly asked interview questions based on Ab Initio products. I have not added the answers here, that you can google the questions and can find out the answer. Make sure prepare the answers for each questions before attending your Ab Initio job interview. You can also download the Ab Initio interview questions PDF version.

Ab Initio Interview Questions and Answers

Here are some possible interview questions and answer to expect when taking an Ab Initio examination:

  1. What is Ab Initio?

Ans.

“Abinitio” is a Latin word which stands for “from the beginning”. Abinitio is a tool that helps in extracting, transforming and loading data. It can as well be used for analyzing data, processing batch, and processing of graphical user interface based parallel.

  1. What is de-partition?

Ans.

De-partition is done for the purpose of reading data from multiple flow or operations and is used for rejoining data records from different flows. Numerous de-partition components are on hand, such as Merge, Concatenation, Gather, and Interleave.

  1. Describe the Grant/Revoke DDL facility and how it is implemented

Ans.

It is a part of D.B.A responsibilities. GRANT means permissions. For instance, GRANT CREATE TABLE, CREATE VIEW AND MANY MORE

REVOKE, on the other hand, stands for cancel the grant (permissions). Therefore, Grant or Revoke both commands depend upon D.B.A.

  1. What is local lookup?

Ans.

  • Local lookup file has records that you can place in main memory
  • Local lookup uses transform function to get back records quicker than having to retrieve them from the disk.
  1. What is Sort Component?

Ans.

In Abinitio, the Sort Component re-orders data. It consists of two parameters – “Key” and “Max-core”.

  • Key: It is one of the parameters for sort component which helps in determining the collation order
  • Max-core: This parameter controls how frequently the sort component should dump data from memory to disk
  1. How can you force the optimizer to use a particular index?

Ans.

Use hints /*+ <hint> */, they act as directives to the optimizer

  1. How do you run a graph infinitely?

Ans.

To run a graph infinitely… The .ksh graph file needs to be called at the end script in the graph. If the name of the graph is xyz.mp then the graph should call the xyz.ksh file.

  1. What is Rollup parameter?

Ans.

Roll-up component assists the users in grouping the records on certain field values. It is a multiple stage function and it comprises initial 2 and Rollup 3.

  1. What is local and formal parameter?

Ans.

Both are graph level parameters. In local, you need to initialize the value at the declaration time whereas global does not need to initialize the data as it will prompt at the time of running the graph for that parameter.

10.What is SANDBOX?

Ans.

A SANDBOX is referred for the collection of graphs and files related to it that are saved in a single directory tree and behaves as a group for the reason of navigation, version control and migration.

You should expect some questions about Graphs like how to run, performance improvement etc ..

4_Explain the methods to improve performance of a graph
5_How to find the number of arguments defined in graph
6_How to run a graph infinitely
7_an exaple of realtime start script in the graph
8_How to Improve Performance of graphs in Ab initioGive some examples or tips
9_How many components in your most complicated graph
10_How to run the graph without GDE
11_How would you do performance tuning for already built graph

Be prepare about the databases, there will be sure questions from there like Joins, Primary & Foreign Keys etc .

12_What are the most commonly used components in a Abinition graph
13_What are Cartesian joins
14_What is semi-join

Be thorough with each components of Ab-initio

15_What are the continuous components in Abinitio
16_How to retrieve data from database to source in that case whice component is used for this
17_What is a Rollup component
18_What is MAX CORE of a component

Most important Android Interview Questions with Answers

Here is a list of 50 important Android Operating system interview questions with their answers.Android is the most popular operating system used in mobile phones. It started a new era on mobile industry with smartphones and tablets. The main feature was its touch screen. Android operating system is initially developed by a company called “Android Inc”. later it acquired by google and then Goggle released this as an open source code. Now most of the IT companies are working with Android Apps developments.

Android is a mobile operating system which was designed and built by Google, using the Linux Kernel and intended to mainly for touchscreen mobile devices like tablets and Smartphones. Its interface for users works on direct manipulation, through the use of touch gestures which slackly match actions that are taken in real world, like tapping, pinching and swiping, to influence objects on the screen, with a virtual keyboard for inputting text. Android remains the largest installed base of all OS (operating systems) and has also been on the top of the tablets that have been sold since 2013.

The Android software development kit (SDK) is used in writing applications (Apps), which are used in broadening the functionality of devices. The Java programming language with full access to the Android APIs also plays a role in writing applications.

There are several institutes providing training for Android development. Now go through all these question and answers before attending your Android job interviews.

Android interview questions with answers

Here are some of the Android interview questions and answers to help you if you are planning on attending an interview.

  1. What is Android?

Ans.

Android is an open source operating system that is mainly used on mobile devices like tablets and Smartphones. Its operations are mainly based on the Linux kernel system which comprises of rich elements that enable developers to develop and run apps that are able to carry out both basic and advanced functions.

  1. What are intents?

Ans.

Intents display messages of notification from within the Android enabled device to the user. Intents are used to notify the user when a particular state occurs, and users have the opportunity to respond to the notification.

  1. What is ANR?

Ans.

ANR is the acronym for Application Not Responding. When an application is unresponsive for a long time, the dialogue shows up to let the user know about the situation.

  1. What is Orientation?

Ans.

Orientation dictates whether the LinearLayout is represented as a column or a roll, when it is set using setOrientationa(). The values are set as VERTICAL or as HORIZONTAL.

  1. What is adb?

Ans.

Adb simply stands for Android Debug Bridge. It presents developers with the power to perform shell commands that are remote. Its major work is to permit and direct communication towards and from the emulator port.

  1. What is the Google Android SDK?

Ans.

Google Android SDK is a set of tools required by developers to enable them write apps on Android enabled devices. It has a graphical interface which imitates an Android handheld environment, enabling them in testing and debugging their codes.

  1. What is Android Architecture?

Ans.

Android Architecture consists of 4 main elements

  • Linux Kernel
  • Android Framework
  • Android Applications
  • Libraries
  1. How can we use escape characters as attributes?

Ans.

Escape characters usually have backlashes before them. For instance, one can create a newline character with the use of ‘\\n’

  1. Differentiate between Activities and Services

Ans.

A user can close or terminate activities anytime he/she wishes to do so. Services, on the other hand, run behind the scene and are able to act in an independent manner. Whether or not there are certain activities being executed, the majority of services run continuously.

  • If your a fresher, then expect this as the first question. Prepare an introduction about Android.
    2_What is Android
  • Question about Google Android SDK
    3_What Is the Google Android SDK
  • Question about Architecture of Android OS
    4_What is the Android Architecture
  • About Android Framework
    5_Describe the Android Framework
  • AAPT in Android
    6_What is AAPT

50+ ASP.Net Interview questions with answers

Here is a list of commonly asked interview questions about ASP.net.ASP stands for active server pages and it is also widely used for web programming after PHP. Download ASP DOTNET interview questions in PDF format.ASP.Net based on Object oriented programming concept. ASP.net is an open source server-side Web application framework that is designed and marketed by Microsoft and intended to help programmers to create dynamic websites, web services and web applications with minimal coding.Here I have collected some good interview questions with their answers.

ASP.net interview questions and answers

There are several questions to expect if you are preparing to attend an ASP.net interview. Here are just a few samples of those questions and their answers:

  1. What is the difference between ASP.net Webforms and ASP.net MVC?

Ans.

Layouts are rendered in ASP.net Web Forms by the use of Page controller pattern. With this, every page is able to have its own controller (code-behind file that posses the request). But ASP.net MVC on the other hand, makes use of Front Controller approach. In this case, requests are processed by a common controller for all pages.

  1. What are the types of Authentication in ASP.net?

Ans.

ASP.net has three types of authentication:

  • Windows Authentication: This makes use of built-in windows security features for user’s authentication.
  • Forms Authentication: This authenticates against a customized users’ list or users in a database.
  • Passport Authentication: This is a centralized authentication service used to validate against Microsoft Passport service.
  1. What is ASP.net?

Ans.

  • ASP.net is a server-side technology that makes use of object-oriented programming approach. In ASP.net, every element is run on the server is treated as an object.
  • ASP.net enables you to build web applications effortlessly by using fully featured programming language such as VB.net or C-Sharp (C#).
  1. What is Global Assembly Cache?

Ans.

Global Assembly Cache (GAC) is used in sharing .NET assemblies. It can be used in the following scenarios:

  • If the multiple application needs to make use of the same assembly.
  • If there are security requirements in the assembly. For instance, if only administrators are permitted to remove the assembly.
  1. What are Strong Names?

Ans.

Strong names are unique names for assemblies. They are similar to GUID in COM components. We can give a strong name for the assemblies whenever we want to deploy the assembly in GAC. They assist GAC in differentiating between two versions.

  1. When does a session actually start?

Ans.

A session starts when a visitor requests your site for the first time. A new session commences when the request lacks any SessionID or the sessionID references a session that has expired. The Session_OnStart event in Global.asax can be used in tracking information that is related to session.

  1. What is Post Back?

Ans.

It is a mechanism that enables a roundtrip of the page between client and a server in request-response model.

  1. What are the ActionResults you know?

Ans.

They include:

  • View
  • PartialView
  • Empty
  • File
  • Redirect
  • Content
  • JSON
  • RedirectToRoute
  1. What are the various ways to send content from one page to another?

Ans.

Response.Redirect()

Server.Transfer()

WebClient.DownloadFile()

  1. How can you secure a WCF service?

Ans.

This can be done in two ways – securing the message sent over and securing the medium of transmission.

  1. How many times will Application_Start event be fired if there are 10 users requesting your application?

Ans.

Application_Start would be fired only once at the level of application. That is when the application is requested for the first time.

  • Prepare about introduction about ASP2_What is ASP
  • Expect a question about difference between normal asp and asp.net3_What is the difference between Classic ASP and ASPNet
  • 4_What is ASPNET
  • Sure question about Cookie in ASP.net5_What is a Cookie
  • 6_Difference between ASP Session State and ASPNet Session State
  • 7_What is the difference between ASP Session and ASPNET Session
  • Question about ASP.Net builtin objects8_What are the major built in objects in Aspnet
  • 9_Difference between ServerTransfer and ResponseRedirect
  • About ServerTransfer and ResponseDirect10_What is a PostBack
  • AutoPostBack11_What is AutoPostBack
  • What is called as round trip in ASP.Net12_What is a round trip
  • Different Types of Cookies13_What are the types of Cookies in Aspnet

General UNIX interview questions with answers

UNIX is an another Operating System like Linux , Windows etc. Here I have collected UNIX interview questions with their answers for your reference. If you require download UNIX Faqs in PDF format.

UNIX is a family of stable multi-tasking, multi-user for desktops, laptops and servers. Like the Microsoft Windows, UNIX systems have a graphical user interface (GUI) which offers an environment that is easy to use.

From the point of view of the user or programmer, Unix systems are typified by a modular design that is occasionally referred to as the “Unix philosophy”, which means that the operating system presents a set of tools that are simple, with each performing a limited, well-defined function, with a unified filesystem as the major way of communication, with a shell scripting and a command language to add the tools together to execute complex workflows.

UNIX interview questions and answers

For anyone preparing to attend a UNIX interview, here are some of the few questions you may likely be asked:

  1. How do you find a process and kill that?

Ans.

If you use the “ps -ef” you get a list of all process and use grep to locate your process and get the PID of that process. After getting the PID you can then make use of the kill command to kill that process.

  1. How do you create an archive file in UNIX or Linux Operating System?

Ans.

An archive can be created in UNIX or Linux by using the tar command you can also create a compressed archive in UNIX by combining tar and gzip

  1. I have read permission on a directory but I am not able to enter it, why?

Ans.

You cannot go into a directory by making use of the cd command if your directory does not have to execute command.

  1. What is the difference between the break and continue, within a UNIX shell scripting?

Ans.

If you use a break within a shell scripting loop construct, it will terminate the entire loop. A continue will terminate the current iteration, but the loop will continue on the next iteration.

  1. How do you debug bash script?

Ans.

Simply add –xv to #!/bin/bash

For instance,

#!/bin/bash –xv

  1. How do you check if file exists on filesystem?

Ans.

If [-f/var/log/messages]

then

echo “File exists”

fi

  1. Provide an example on how to write function

Ans.

Function example {

echo “Hi everyone!”

}

  1. What is Paging?

Ans.

Only required memory pages are moved to main memory for execution

  1. How do you set the path in UNIX?

Ans.

set path = [directory path]

  1. What is tee command?

Ans.

Tee command is used for

  • Sending data from the standard point
  • Sending it to standard output
  1. What are filters?

Ans.

A Filter is a program which filters the data prior to execution on application OR database

  1. What is Shell?

Ans.

A shell operates as a boundary between the user and the system

  1. What is inode?

Ans.

The inode is a data structure in a file system. Each inode is able to store the attributes and the location (s) of the disk block of the object’s data.

  1. What is ephemeral port?

Ans.

Operating systems use Ephemeral ports for client sockets

  1. How do you create readonly file?

Ans.

Use,

touch filename.txt

chmod 400 fileName.txt

 

  • Quick introduction about UNIX OS

    5_What is unix

  • Introduction about the term shell in UNIX

    2_What is a shell

  • Should be thorough about session

    3_Define session

  • Question about Signal in UNIX

    4_What do you mean by signal

  • Question about Message queue

    6_Define message queue

  • Directory and filenaming in UNIX

    7_Define directory and filename

  • Definition of terms program and process

    8_Define program and process

  • Different file types in UNIX

    9_List down the different file types

  • 10_What are the options available to determine the group ID of the new file
  • About sticky bit in UNIX

    11_Define sticky bit

  • Question about page fault

    12_What is called a page fault

  • 13_What do you mean by u-area (user area)
  • Types of buffering in UNIX

    14_What are the different types of buffering is supported by UNIX

Basic & Advanced MySQL Interview Questions with Answers

MySQL RDBMS is the most popular opne source database used mainly with PHP and another online applications. Here is some most commonly asked interview qyestions collections about MySQL. Download Complete PHP Faqs in PDF.If you are a PHP programmer or an online software developer, you should be thorough with basic RDBMS ( Relational Databse Management system ). The questions you can expect from this topic are about

  • Creating, deleting, altering Databases and tables
  • Connection with database
  • Primary keys , index keys and foreign keys
  • How you start designing tables as per the requirement
  • Selection query
  • Optimizing the queries with left and right join
  • Aggregating functions like SUM
  • Selecting the unique rows
  • avoiding the duplicate rows
  • Search in Mysql table
  • Technical features and General knowledge topics about MySQL

Most of the companies are working with this MySQL tables and there are a lot of job chances in this field as database  administrator  and programmer. Please go through all of these followed questions with their answers before attending the interview.

About MySQL

MySQL is an open-source relational database management system (RDBMS). The name is derived from a combination of “My” which stands for the name of the daughter of the co-founder Michael Widenius, and “SQL” which is stands for Structured Query Language.

MySQL is owned by Oracle, though initially owned and sponsored by a single for-profit firm, the Swedish company MYSQLAB. The MYSQL development project makes its source code accessible under the GNU General Public License terms, including a range of propriety agreements. You can get various paid editions with additional functionality for propriety use.

MySQL interview questions and answers

Writing MySQL exam can be a bit tricky. But if you are getting set for an interview, here are a few possible questions you might be asked and their answers.

  1. What is MySQL?

Ans.

MySQL is an open-source DBMS that is built, supported and distributed by MySQL AB. It is now owned by Oracle.

  1. Why do we use MySQL?

Ans.

MySQL database server is dependable, fast and user-friendly. One can download the software from the internet and as freeware.

  1. What is the default port for MySQL Server?

Ans.

The default port for MySQL server is 3306

  1. What is REGEXP?

Ans.

REGEXP is a pattern match in which matches pattern anywhere in the search value

  1. What does a TIMESTAMP do on UPDATE CURRENT_TIMESTAMP data type?

Ans.

When the table is created, Zero is used for updating the TIMESTAMP column. UPDATE CURRENT_TIMESTAMP modifier updates the timestamp field to current time whenever other fields of the table are changed.

  1. What does myisamchk do?

Ans.

It is used for compressing the MyISAM tables thereby reducing their disk or memory usage.

  1. What do you understand by federated tables?

Ans.

They let you have access to the tables which are located on other databases on other servers.

  1. How do we find out the auto increment that was assigned on Last insert?

Ans.

LAST_INSERT_ID will return the last value assigned by Auto increment and it not mandatory for the table name to be specified.

  1. How do you login to MySQL using Unix shell?

Ans.

To login, we can make use of this command:

#[mysql dir]/mysql –h hostname –u<UserName> -p<password>

  1. Differentiate between CHAR_LENGTH and LENGTH

Ans.

While CHAR_LENGTH is character count, the LENGTH is a byte count. The numbers are the different for Unicode and other encodings but the same for Latin characters.

  1. How can you see all the indexes defined for a table?

Ans.

You can define indexes for the table by:

SHOW INDEX FROM <tablename>;

  1. What are the column comparisons operators?

Ans.

The =, <>, <=, <, >=, >, <<, >>, <=>, AND, OR, or LIKE operators are used in column comparisons in SELECT statements

  1. What is InnoDB?

Ans.

InnoDB is a transaction safe storage engine developed by Inno Oy, now Oracle Corporation.

  1. How many columns can you use in creating Index?

Ans.

You can only create a maximum of 16 indexed columns for any standard table

  1. What do you mean by % and _ in the LIKE statement?

Ans.

% corresponds to 0 or more characters. But _ is exactly one character in the LIKE statement.

  • 2_What’s MySQL
  • 3_Why use the MySQL Database Server
  • 4_What is the technical features of MySQL Server
  • 5_What are the column comparisons operators
  • 6_How do you get the number of rows affected by query
  • 7_What are HEAP tables in MySQL
  • 8_How do you return the a hundred books starting from 25th
  • 9_How would you write a query to select all teams that won either 2 4 6 or 8 games

Datastage Interview questions with Answers

Datastage is an Extract, Transform and Load ( ETL ) tool from IBM and part of their IBM InfoSphere. Here I have collected more than 70 interview questions with their answers about Datastage.Download Complete IBM Datastage Interview questions PDF.All these questions are frequently asked ones and better prepare all these before attending your Datastage interview . You can also refer Datastage Tutorials and PDF training materials.

DataStage is “ETL tool, which extracts data, transforms it and applies business rules and then loads it to any target.” According to Wikipedia, “IBM InfoSphere DataStage is an ETL tool and part of the IBM Information Platforms Solutions suite and IBM InfoSphere. It uses a graphical notation to construct data integration solutions and is available in various versions such as the Server Edition, the Enterprise Edition, and the MVS Edition.”

DataStage interview questions and answers

Are you booked for a DataStage interview? You may consider reading these few questions and answers before attending. They may be of great help to you in the long run.

  1. What are the areas of application?

Ans

Regardless of your field, DataStage offers you the unique privilege of storing and retrieving your data without any negative impact on your performance.

  1. What are the benefits of DataStage?

Ans

DataStage has three benefits. They are discussed below:

  • Security controls: These offer researchers to have some designated areas for private uses. The researchers and their group leader only can have access to the area. For the benefit of the whole group. There are “collaborative” and “shared” areas where they can put files that are meant for the group.
  • Web interface: This allows annotation of files to the users. They can also access any data from their personal computer at home.
  • Repository: This option is also available for storing data permanently.
  1. How many areas for files does DataStage have?

Ans

DataStage has three storage areas for files. These are:

  • Private: In this storage area, only the owner of a file and the administrator(s) can see the stored files.
  • Shared: All members can see the files. However, they can only read the files without the liberty to amend it. It is read-only access they have.
  • Collaborative: All the members can see a file. They can also edit the contents of a file because they have the right to read and write to the files.
  1. What are the components of DataStage?

Ans

DataStage has four main components which are:

  • Designer: This is where you can create your job, compile and run it. It can display file layouts, transforms, routines, and tables that are defined in a particular job.
  • Director: All the DataStage jobs you have can be run and monitored here. Scheduling and validating DataStage jobs can also be done here.
  • Administrator: Administrator allows you to create some projects and users as well as specify roles for these. It is generally used to add or delete projects, specify the defaults for the general server, set the properties of a project and provide an interface for the DataStage repository.
  • Web Console: If you ever need to change your login details, this is where you can do it.
  1. What are the features of DataStage?

Ans

Some of the main features are:

  • It can extract data from any type or number of database.
  • It has aggregates data where SQL SELECT statements used for data extraction can be modified.
  • It has some functions and transforms that can be used for data conversion. To extend the functionality, you can design your own transform for use at any time.
  • It can be used to modify the definitions of a table while designing your application.
  • Prepare for this first question very well. Introduction about IBM Datastage tool
    6_What is DataStage
  • There are mainly two tools used for the same purpose. Informatica and Datastage. Let us prepare the main difference bewteen these two ETL tools
    2_What is the difference between DataStage and Informatica
  • A sure questions ie about the main components of datastage
    3_What are the components of Ascential Data Stage
  • Question about System variables
    4_What are System variables
  • 5_What are the enhancements made in datastage 75 compare with 70
  • About Merage
    7_What is a merge
  • About Sequencers
    8_What are Sequencers
  • Introduction about version COntrol in Datastage
    9_What is version Control
  • Another important Datastahe interview question about Active Stage and Passive stage
    10_What is Active and Passive Stage
  • Question about Datastage features11_What are the main features of datastage
  • About Data aggregation
    12_Define data aggregation

General knowledge level Zoology questions and answers for Interview , Test , Exams

Here is a list of 53 Zoology questions with their answers. These questions will be useful for facing interview or for preparing Zoology test or exam. Download Zoology Questions PDF file

Most of the entrance exams for B.Tech , MBBS etc and tests for Government job vacancies will contain Zoology questions as part. So it will be useful to prepare these questions and answers for facing those exams and improving your general knowledge level.

  • 54_BCG vaccination (Bacillus Calmette Guerine) is injected to get immunity from
  • 53_Which of the following vitamins is synthesised in the body by intenstinal bacteria
  • 52_For which one among the following diseases no vaccine is yet available
  • 51_Which one of the following disease is Inheritable
  • 50_BCG vaccination (Bacillus Calmette Guerine) is injected to get immunity from
  • 49_Which of the following vitamins is synthesized in the body by intestinal bacteria
  • 48_For which one among the following diseases no vaccine is yet available
  • 47_Which one of the following disease is Inheritable
  • 46_Which of the following disease is not a caused by viruses
  • 45_What is the pH level of blood of a normal person
  • 44_A typical human ribcage consists of how many ribs
  • 43_In which one of the following animals is skin a respiratory organ
  • 42_Which one of the following is responsible for converting milk into curd
  • 41_Which one of the following is a vitamin
  • 40_Which chamber of human heart pumps fully oxygenated blood to aorta and hence to the body
  • 39_Which one of the following bacteria helps in improving the soil fertility
  • 38_In which one of the following animals is respiration done by skin
  • 37_Which one of the following parts of the pitcher plant becomes modified into a pitcher
  • 36_Production of which one of the following is a function of the liver
  • 35_Which one of the following part of human brain is the regulating centre for swallowing and vomiting

Important Oracle Interview Questions with Answers

Here is a list of 60 interview questions about Oracle Database with their answers. The list contains questions useful for basic, freshers and experienced oracle professionals.Download Complete Oracle Interview Questions PDF. Each question contains their answer also. Its a good practice to go through all of these questions before attending the interview.

Are you preparing to attend an Oracle interview soon? Here are a few questions and answers you may find interesting.

  1. What is RAW datatype?

Ans.

RAW data type is used in storing values in binary data format. The maximum size of a RAW in a table is 32767 bytes.

  1. What is BLOB datatype?

Ans.

A BLOB data type is a binary string with a varying length which is used in storing two gigabytes memory. Length should be stated in Bytes for BLOB

  1. What is NULL value in Oracle?

Ans.

NULL value represents unknown or missing data. It is used as a place holder or represented as a default entry indicating that no actual data is present.

  1. What is WITH CHECK OPTION?

Ans.

The WITH CHECK option clause specifies the level of check to be done in DML statements. It aids in preventing changes to a view that would produce results not contained in the sub query.

  1. What is the difference between varchar and varchar2 data types?

Ans.

Varchar can store up to 2000 bytes and varchar2 can store up to 4000 bytes. While Varchar will occupy space for NULL value, Varchar2 will not occupy any space. They are differentiated by space.

  1. What is the use of NVL function?

Ans.

The NVL function is used for replacing NULL values with given or another value. E.g.  NVL(Value, replace value)

  1. How do we get field detail of a table?

Ans.

To get the field of a specified table use, Describe <Table_Name>

  1. What is an ALERT?

Ans.

An alert is a window which appears in the center of the screen and overlays a portion of the current play.

  1. What is the fastest query method to fetch data from the table?

Ans.

You can use ROWID to fetch Row from the table. The use of ROW ID is the fastest query method for fetching data from the table.

  1. What is the parameter mode that can be passed to a procedure?

Ans.

The parameter modes that can be passed to a procedure are IN, OUT and INOUT

  1. What is hash cluster?

Ans.

Hash Cluster is a technique used for storing the table to make it faster to retrieve. It order to retrieve the rows from the table, apply the hash value on the table.

  1. What are SET operators?

Ans.

SET operators are used with two or more queries. The operators are Union, Union All, intersect and Minus.

What is a view?

View is a logical table that is based on one or more tables and views. The tables which the view is based upon are called Base Tables and it contains no data.

  • Expect this as the first questions, if you are a fresher. Prepare answer for an introduction about Oracle
    2_What is Oracle table
  • Question about Clusters
    3_What are Clusters
  • Index in database. This is an important section that you should prepare well.
    4_What is an Index
  • What is called as Views in RDBMS. What are the uses
    5_What are the advantages of views
  • Tell about various types of queries that you know
    6_What are the various types of queries
  • Clusterd and non-clusterd index
    7_What is the difference between clustered and a non-clustered index
  • Introduction about Table Space
    8_What is a Tablespace
  • 9_Why use materialized view instead of a table
  • 10_What does ROLLBACK do
  • 11_Compare and contrast TRUNCATE and DELETE for a table
  • 12_what is null value
  • 13_Define transaction
  • 14_what is the difference between sql&oracle
  • 15_What are different Oracle database objects
  • 16_What is hash cluster
  • 17_What is a User_exit
  • 18_What is schema
  • 19_What are Roles
  • 20_What are the dictionary tables used to monitor a database spaces
  • 21_What is a SNAPSHOT
  • 22_What is a database instance
  • 23_What are parameters
  • 24_What are the different file extensions that are created by oracle reports
  • 25_What are clusters