Technology Questions

The Application Cache concept introduced by HTML5 means that a web application is cached, and accessible without an internet connection.

There are three advantages of Application Cache:

1.Offline browsing - users can use the application when they're offline

2.Speed - cached resources load faster

3.Reduced server load - the browser will only download updated/changed resources from the server

.NET does not support multiple inheritance directly because in .NET, a class cannot inherit from more than one class. .NET supports multiple inheritance through interfaces.

The application layer of an R/3 System is made up of the application servers and the message server. Application programs in an R/3 System are run on application servers. The application servers communicate with the presentation components, the database, and also with each other, using the message server. All the data are stored in a centralized server. This server is called database server.

bcoz interface does not contains any initializers and constructors to initialize its data members.

A foreign key is a reference to another table. It is used to establish relationships between tables. For example, relationship between employee and professor table. One employee can have multiple professors. The Primary key of employee becomes foreign key of professor.
Example:
create table employee ( id number NOT NULL, professor_id NOT NULL, Name varchar(200) Constraint prim_id Foreign key(id) references professor(professor_id) );

The diamond problem is an ambiguity that can occur when a class multiply inherits from two classes that both descend from a common super class

DriverManager is a class in java.sql package. It is the basic service for managing a set of JDBC drivers.

As far PHP concern it only support single Inheritance in scripting. we can also use interface to achieve multiple inheritance.