Technology Questions

Log shipping is the process of automating the backup of database and transaction log files on a production SQL server, and then restoring them onto a standby server. Enterprise Editions only supports log shipping. In log shipping the transactional log file from one server is automatically updated into the backup database on the other server. If one server fails, the other server will have the same db and can be used this as the Disaster Recovery plan. The key feature of log shipping is that it will automatically backup transaction logs throughout the day and automatically restore them on the standby server at defined interval.

Scope resolution operator allows a program to reference an identifier in the global scope that is hidden by another identifier with the same name in the local scope.

The following are the two types of assemblies:

          =>  Private Assembly - Refers to the assembly that is used by a single application. Private assemblies are kept in a local folder in which the client application has been installed.

          =>  Public or Shared Assembly - Refers to the assembly that is allowed to be shared by multiple applications. A shared assembly must reside in Global Assembly Cache (GAC) with a strong name assigned to it.

For example, imagine that you have created a DLL containing information about your business logic. This DLL can be used by your client application. In order to run the client application, the DLL must be included in the same folder in which the client application has been installed. This makes the assembly private to your application. Now suppose that the DLL needs to be reused in different applications. Therefore, instead of copying the DLL in every client application folder, it can be placed in the global assembly cache using the GAC tool. These assemblies are called shared assemblies.

- Packet data speed is higher in 3G, and it is up to 384 KBPS
- Voice and sms speed is also 384 KBPS in 3G
- 2G utilizes different switching techniques for voice and data, where as  3G uses single switching, irrespective of data
- 3G has at least 2MB of data link of a mobile, where in 2G the data rate is in KBPS
- 3G has WiMAX facility for faster VOIP and internet
- 2G uses GSM TDMA technology with narrowband 200Khz.
- 3G uses CDMA technology with broadband 5Mhz, with same frequency carrier and time.

It is an MVS message that indicates the presence of a duplicate catalogue in the database. This problem can be fixed by removing one of the entries and then adding a new one.

There are three ways that can be used in order for a Thread to be created:

A class may extend the Thread class.

A class may implement the Runnable interface.

An application can use the Executor framework, in order to create a thread pool.

The Runnable interface is preferred, as it does not require an object to inherit the Thread class. In case your application design requires multiple inheritance, only interfaces can help you. Also, the thread pool is very efficient and can be implemented and used very easily.