Technology Questions

There is no difference between int and int32. System. Int is an alias name for System.Int32 which is a .Net Class.

LINQ is a programming model that is the composition of general-purpose standard query operators that allow you to work with data, regardless of the data source in any .NET based programming language. It is the name given to a set of technologies based on the integration of query capabilities into any .NET language.

A PHP Session persist the user information to be used later. For example, user name, password, shopping item details. The session is temporary and will be removed soon after the user has left the web site. The session can be persisted for long term usage on databases like MySQL. Each session is identified by a unique Id number for every visitor. The first step to use PHP session is to start the session. The starting session must precede the operations like HTML or the other.

The statement session_start() starts the PHP session and registers the user’s information on the server.

No difference. There is a difference between obtain first and obtain next for an area sweep, but not when current on the owner in a set.

Windows Server Backup is a feature released for the Windows 2008 that provides a number of solutions on backing up the data on your computer in case of a system failure or any other issue. Windows Server Backup can backup a few files to a whole server. The server backup is accessible through command lines and a management console

Aggregate functions in SQL are used to perform calculation on data. These functions are inbuilt in SQL and return a single value.

SUM( )

SUM function returns the sum or addition of all NOT NULL values of a column. For e.g. I have a Table employee with the fields id, name, salary and I want the sum of all salaries, I can use SUM function as shown
SELECT SUM(emp_salary) from employee;
Hence, if my column emp_salary has values 20,000, 22,000, 21,000; the output will be 63,000

AVG( )

 
AVG function returns the average of all NOT NULL values of a column. For e.g. I have a Table employee with the fields id, name, salary and I want the average of all salaries, I can use AVG function as shown
SELECT AVG(emp_salary) from employee;
Hence, if my column emp_salary has values 20,000, 22,000, 21,000; the output will be 21,000

COUNT( )

COUNT function returns the number of rows or values of a table. For e.g. I have a Table employee with the fields id, name, salary and I want the count of all rows, I can use COUNT function as shown
SELECT COUNT(*) from employee;

Max ( ) and Min ( )

MAX function returns the largest value of a column in a table. For e.g. I have a Table employee with the fields id, name, salary and I want the maximum salary of an employee, I can use MAX function as shown
SELECT MAX(emp_salary) from employee;
Hence, if my column emp_salary has values 20,000, 22,000, 21,000; the output will be 22,000

MIN function returns the smallest value of a column in a table. For e.g. I have a Table employee with the fields id, name, salary and I want the minimun salary of an employee, I can use MIN function as shown
SELECT MIN(emp_salary) from employee;
Hence, if my column emp_salary has values 20,000, 22,000, 21,000; the output will be 20,000

JDK is Java Development Kit which is for development purpose and it includes execution environment also.

JVM is Java Virtual Machine which is a run time environment for the compiled java class files .Hence you will not be able to compile your source files using a JVM.