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Great opportunity in Haryana SSC for Computer Science Aspirants:-- Category 1 : 119 post of Computer Instructor Category 3: 122 post for COPA

Learning GIS programming: An overview   The diversity of programming languages and tools being used in GIS (in general in the Geospatial industry) today is truly staggering. Depending on what the position requires, one would be expected to have expertise in SQL, python, C++, Java or JavaScript, Flex and PHP (just to name a few). Knowledge and competence in programming is a essential skill set and a critical requirement for most Geospatial job opportunities these days.  A vast majority of job openings in the Geospatial industry require some expertise in programming, application development and software management. As Geospatial professionals/graduates/students, some of us overlook the importance of programming in our careers. Some of us believe that our spatial skill sets are niche enough to compensate for the lack of our programming expertise. Well that might not be totally wrong. However, knowledge of programming is most certainly goin...

Java is a strongly typed language. Hence every element to be declared, must strictly define its type. Example:   int x =10; char c; Here, x is a variable of the type ‘int’ which is initialized by a value of 10 and c is a variable of type ‘char’.

Comments are description given by the programmer within the program. So that if another programmer looks at the program,he can easily understand the program by reading the comments. The characters or words or anything which are given in comments section won’t be considered by java compiler for compilation process and will be ignored by java compiler during compilation.

Objects are anything that exists in the world. A Class is a blueprint to develop objects. If you consider creating objects like chair, table, cupboard, then you need to create class called Furniture. A class contains variables and methods. Variables are attributes or properties. Method perform functions or actions.

Three things need to be done to make a java program work. They are, 1. Create, 2. Compile, and 3. Run

As you know, a function is a group of instructions combined together to perform a task. There are so many inbuilt functions in SQL to perform many arithmetic tasks. They are, Aggregate functions Scalar functions Group by function Having function

SQL EXCEPT clause is also same as SQL INTERSECT. But, EXCEPT clause returns all records from the 1st SELECT statement, except those are found in the 2nd SELECT statement.

A  network topology  is the arrangement of a  network , including its nodes and connecting lines. There are two ways of defining  network  geometry: the physical  topology  and the logical (or signal)  topology .

Dear Reader, NTRO released the admit card to the shortlisted candidates on their registered mail ID. Shortlisting criteria is as follows:

What is DBMS? Advantages and Disadvantages of DBMS. DBMS  A  database management system  is the software system that allows users to define, create and maintain a database and provides controlled access to the data.

Dear Readers, Download PDF Copy of HTML Notes, Very Useful for upcoming exams.

Introduction to GIS This lecture will cover: What GIS is What GIS does What GIS does not do GIS and archaeology

SQL Statement Syntax

The Union Clause is used to combine two separate select statements and produce the result set as a union of both the select statements.

Syllabus:-

IMPORTANT INFORMATION : The Computer Based Examination for NTRO

Text Files .log :  Log File .wpd :  WordPerfect Document .odt :   OpenDocument Text Document .pages :   Pages Document

The Detailed Difference and discussion is as follows

A Database is a collection of related data organised in a way that data can be easily accessed, managed and updated. Any piece of information can be a data, for example name of your school. Database is actualy a place where related piece of information is stored and various operations can be performed on it.

Linked List is a linear data structure and it is very common data structure which consists of group of nodes in a sequence which is divided in two parts. Each node consists of its own data and the address of the next node and forms a chain. Linked Lists are used to create trees and graphs.

A Queue is defined by its property of FIFO, which means First in First Out, i.e the element which is added first is taken out first. Hence we can implement a Queue using Stack for storage instead of array.

Queue is also an abstract data type or a linear data structure, in which the first element is inserted from one end called REAR (also called tail), and the deletion of existing element takes place from the other end called as FRONT (also called head). This makes queue as FIFO(First in First Out) data structure, which means that element inserted first will also be removed first.

1.        In the deletion operation of max heap, the root is replaced by: (A) next available value in the left sub-tree. (B) next available value in the right sub-tree. (C) first element of the last level (D) last element of the last level

A program in the execution is called a Process. Process is not the same as program. A process is more than a program code. A process is an 'active' entity as opposed to program which is considered to be a 'passive' entity. Attributes held by process include hardware state, memory, CPU etc. Process memory is divided into four sections for efficient working :

Alias is used to give an alias name to a table or a column. This is quite useful in case of large or complex queries. Alias is mainly used for giving a short alias name for a column or a table with complex names.

Stack is an abstract data type with a bounded(predefined) capacity. It is a simple data structure that allows adding and removing elements in a particular order. Every time an element is added, it goes on the top of the stack, the only element that can be removed is the element that was at the top of the stack, just like a pile of objects.

Before studying searching algorithms on array we should know what is an algorithm? An algorithm is a step-by-step procedure or method for solving a problem by a computer in a given number of steps.

Merge Sort follows the rule of Divide and Conquer . In merge sort the unsorted list is divided into N sublists, each having one element, because a list consisting of one element is always sorted. Then, it repeatedly merges these sublists, to produce new sorted sublists, and in the end, only one sorted list is produced.

Order by clause is used with Select statement for arranging retrieved data in sorted order. The Order by clause by default sort data in ascending order. To sort data in descending order DESC keyword is used with Order by clause.

Like clause is used as condition in SQL query. Like clause compares data with an expression using wildcard operators. It is used to find similar data from the table.

Quick Sort, as the name suggests, sorts any list very quickly. Quick sort is not a stable search, but it is very fast and requires very less additional space. It is based on the rule of Divide and Conquer (also called partition-exchange sort ). This algorithm divides the list into three main parts :

Keys are very important part of Relational database. They are used to establish and identify relation between tables. They also ensure that each record within a table can be uniquely identified by combination of one or more fields within a table.

Selection sorting is conceptually the most simplest sorting algorithm. This algorithm first finds the smallest element in the array and exchanges it with the element in the first position, then find the second smallest element and exchange it with the element in the second position, and continues in this way until the entire array is sorted.

It is a simple Sorting algorithm which sorts the array by shifting elements one by one. Following are some of the important characteristics of Insertion Sort.

Bubble Sort is an algorithm which is used to sort N elements that are given in a memory for eg: an Array with N number of elements. Bubble Sort compares all the element one by one and sort them based on their values.

Sorting is nothing but storage of data in sorted order, it can be in ascending or descending order. The term Sorting comes into picture with the term Searching.

Time complexity of an algorithm signifies the total time required by the program to run till its completion. The time complexity of algorithms is most commonly expressed using the big O notation .

Introduction to Data Structures Data Structure is a way of collecting and organising data in such a way that we can perform operations on

Comparison of OSI Reference Model and TCP/IP Reference Model Following are some major differences between OSI Reference Model and TCP/IP Reference Model, with diagrammatic comparison below.

Types of Operating Systems Following are some of the most widely used types of Operating system.

SQL Join is used to fetch data from two or more tables, which is joined to appear as single set of data. SQL Join is used for combining column from two or more tables by using values common to both tables. Join Keyword is used in SQL queries for joining two or more tables. Minimum required condition for joining table, is (n-1) where n , is number of tables. A table can also join to itself known as, Self Join .

TCP/IP means Transmission Control Protocol and Internet Protocol. It is the network model used in the current Internet architecture as well. Protocols are set of rules which govern every possible communication over a network. These protocols describe the movement of data between the source and destination or the internet. These protocols offer simple naming and addressing schemes.

Banker’s algorithm is a deadlock avoidance algorithm. It is named so because this algorithm is used in banking systems to determine whether a loan can be granted or not.

CPU scheduling is a process which allows one process to use the CPU while the execution of another process is on hold(in waiting state) due to unavailability of any resource like I/O etc, thereby making full use of CPU. The aim of CPU scheduling is to make the system efficient, fast and fair.

What is a Deadlock? Deadlocks are a set of blocked processes each holding a resource and waiting to acquire a resource held by another process.

  The Open System Interconnection (OSI) model defines a networking framework to implement protocols in seven layers. You must at first understand that OSI model is not tangible rather it is conceptual.