Relational model includes several types of constraints whose purpose is to maintain the accuracy and integrity of the data in the database. The major types of integrity constraints are: 1. Domain Constraints All the values that appear in a column of a relation must be taken from the same domain. A domain usually consists of…
There are several reasons for this, the most obvious being that it’s good for branding. Nothing looks more unprofessional than a brand that hosts its website at brandname.wordpress.com. This is because as a general rule, the websites that buy and maintain a domain name tend to be those that are more reputable and more established….
A database is a collection of information or data organized and presented to serve a specific purpose. A computerized database is an updated, organized file of machine readable information that is rapidly searched and retrieved by computer. Data are binary computer representations of stored entities. Data can exist in many forms. Data can be defined…
Advantages of Database Management System are: 1. Data Independence Database application programs are independent of the details of data representation and storage. The conceptual and external schemas provide independence from physical storage decisions and logical design decisions respectively. 2. Efficient Access A DBMS provides efficient storage and retrieval mechanisms, including support for very large files,…
A Spyware as the name suggest is a program used to spy on the computer system. This program will try to get all the confidential and sensitive information such as your bank account numbers, passwords etc. Then this confidential data is misused to access user’s accounts. Spyware can also change the configuration of your computer,…
Web Hosting comes in all different shapes and sizes, with different setups suitable for different types of a webmaster. In general, hosting can be broken up into the following categories: 1. Shared Hosting This is usually the cheapest form of hosting because it’s the most economical when it comes to the use of hardware. Shared…
The term “spam” refers to unsolicited commercial email (UCE) or unsolicited bulk email (UBE). It is flooding the Internet with many copies of the same message, in an attempt to force the message on people who would not otherwise choose to receive it. It is also referred as junk email. Unsolicited email mostly contains advertisements…
Hackers and crackers are the software programmers who use dubious ways to get control over your computer and systems. The intent of both hackers and crackers is to gain control over your computer so that they can get sensitive confidential information. They then use this information against you by stealing money, personal data, pictures, bank…
A domain name is a bit like your physical address in that it’s how people find you out there on the World Wide Web. That’s why we call the bar at the top of a web browser the address bar – it’s where you enter a domain name to find a website. If a domain…