Database

Database
A database consists of an organized collection of data for one or more multiple uses. One way of classifying databases involves the type of content, for example: bibliographic, full-text, numeric, image. Other classification methods start from examining database models or database architectures: see below. Software organizes the data in a database according to a database model. As of 2010 the relational model occurs most commonly. Other models such as the hierarchical model and the network model use a more explicit representation of relationships.

In computing, databases are sometimes classified according to their organizational approach. The most prevalent approach is the relational database, a tabular database in which data is defined so that it can be reorganized and accessed in a number of different ways. A distributed database is one that can be dispersed or replicated among different points in a network. An object-oriented programming database is one that is congruent with the data defined in object classes and subclasses.

Computer databases typically contain aggregations of data records or files, such as sales transactions, product catalogs and inventories, and customer profiles.

Typically, a database manager provides users the capabilities of controlling read/write access, specifying report generation, and analyzing usage. Databases and database managers are prevalent in large mainframe systems, but are also present in smaller distributed workstation and mid-range systems such as the AS/400 and on personal computers. SQL (Structured Query Language) is a standard language for making interactive queries from and updating a database such as IBM's DB2, Microsoft's Access, and database products from Oracle, Sybase, and Computer Associates.

-----------------------------------------

Uses for a Database

Databases for Businesses
The business world depends on databases 24 hours a day/seven days a week. Inventory, order processing, payroll, accounting, shipping and transportation routing are often tracked within a main database that keeps the company functioning.

Databases for Educational Institutions
From elementary schools to colleges, educational institutions have used databases to keep track of students, grades, transfers, transcripts and other student data. There are even specialized database packages geared toward schools and colleges.

Databases for Non-Profit Organizations
Like businesses and educational institutions, non-profit organizations must have a system to keep track of information. Many charities and other non-profit groups use a database for keeping track of donations, volunteers, hours served in the community, clients helped and other information related to the organization.

Databases for Household and Family Management
The database also has a home in household and family management for many individuals and families. Many individuals/families use a database to keep track of family birthdays, bills and expenses within a home; addresses of friends and relatives; movie/DVD collections; and other lists.

Databases In Use Everyday
Each time you make a purchase and the sales clerk asks for a your address or ZIP code, your information is kept and stored in a customer database. These collections of data are used to send mailings of special offers, discounts and other deals.

-----------------------------------------

Why Use a Database?
So, what possible use could you have for a database on your website? After all, you are just creating a site for yourself, your friends and your family.
As I mentioned earlier, there are a myriad of uses for databases. I'm sure it is easy to imagine all of the uses for a database on a commercial web site like an online store. You could store visitor information for logging in, purchase information, order logs, bookkeeping information, company reports, pricing structures, account information and the list goes on.

But what about personal stuff? Well, imagine this. You started a site for you and your family. You have a few pages for your family, your parents have a few pages and you just added some pages about your friends. Now your site just seems to keep growing and you don't really have the time to keep up with your own stuff let alone all of the things your family and friends keep sending you.
For example, you started a page so that you and your friends can borrow each others DVDs. Your page keeps track of who has what DVD and who is the original owner of the DVD. Each time a DVD changes hands someone sends you an email and you have to change the information on the website.

Another example. Your parents have 7 grandchildren. They love to keep up with their grandchildren's' activities. So, they are constantly sending you each grandchild's schedule of events to post. You get sports schedules, school activities and recitals just to name a few.

You also created a community page for your visitors. On it you have the names, email addresses and telephone numbers of your family and friends. The trouble is your friends and family seem to keep adding their friends and family and you keep getting all of the emails asking you to add more and more people.
Getting tired just thinking about it? Can you see how a database could be your friend?

If you could create a database driven DVD checkout system, calendar of events and community contacts you could save yourself a ton of time by letting your users do the updating instead of you through some simple web forms that you create and then use your database to update your pages automatically.
back to top

-----------------------------------------

What Types of Databases are There?
You wouldn't believe.
DBMSs (Data Base Management Systems) come in many different shapes, sizes and flavors, however, there are two basic categories: Enterprise and Personal.
(In case you are confused, DBMS refers to the software that handles moving the data in, out and around your database while the term database refers to the actual body of data that you are storing.)
Enterprise DBMSs are designed primarily for use with corporations, governments and any other function that would require the database to handle large amounts of data coming in and out. Information Technology folks refer to this as scalability which simply means how well the database handles multiple simultaneous transactions (the handling of data). For example, a high scalability would mean that the database can handle everything from a few transactions an hour to thousands of transactions or more happening at the same time.
Some examples of Enterprise DBMSs that you might have heard of would be Microsoft's SQL (pronounced sequel) Server, Oracle or IBM's DB2.
Personal DBMSs are generally not highly scalable. They are intended to be used as learning tools or in low demand situations like you may run into while working on your personal projects. Depending on the DBMS, you might even find good uses for a personal DBMS in small business. Many Enterprise DBMSs also have personal versions like Oracle that was mentioned above. Other companies
produce separate products like Microsoft's Access which are very similar to their Enterprise product.

-----------------------------------------

Since then, spreadsheets have become much more sophisticated tools. But they still fall far short of databases. Here's why a database is still a better tool for business:
• Easier to share. You can have two or more people editing a database at the same time. But spreadsheet users have to wait until nobody is using a file before it's free for them to use.

• Better security. Along with the ability to better share information is the ability to better secure it. You can protect private information from wandering mice better with a database. You can also protect users from their own mistakes, like adding up the wrong column or forgetting to include sales tax in the price quote.

• More efficient. Databases are relational, allowing you to link related tables to minimize duplication. Here's an example. Say you have a mailing list that includes 20 real estate agents at the same office. All of them have the same company name, address, phone number and fax. In a spreadsheet, you would have to duplicate that information 20 times for each agent. In a relational database manager, you enter that information once, then link or "relate" it to each of the 20 agents.

• Better reporting. With a database, you can format the same data many ways in reports. Here's an example. For monthly sales reports, you want to look at sales by person, by region and by product. In a spreadsheet, you basically have to enter or copy that information three times in three spreadsheets to get the desired reports. In a database, you enter it once and then use the reporting features to compile the data in the three formats with a click of the button.
• Greater capacity. Databases also have capacity to hold much greater numbers of records (into the billions).

• Easier to maintain. What makes spreadsheets so simple to use -- the fact that the programming and the formatting are together on one page with the data -- also makes them hard to maintain. Every place I go where people use spreadsheets for database activities, such as list management and process tracking, I spend time fixing spreadsheets because someone messed up the formatting while changing the data. You don't have that problem with databases.

• Less duplication. There are two kinds of duplication with spreadsheets.
First, there is file duplication. Because you can't share the price-quote spreadsheet, everyone makes a personal copy. Second is duplication of source data. Nine of 10 spreadsheets duplicate information already housed in a database, such as an accounting program.
In short, databases require a greater investment in training. But the return is greater than any spreadsheet.


So when should you use spreadsheets? I like them for two circumstances:

• When compiling information from diverse sources. For example, you want to compare your company's financial ratios with those of industry standards supplied by your accountant.

• When you are doing a one-time analysis. There isn't a faster tool for building a simple snapshot that you might not use again.
Of course, you're free to use spreadsheets however you want. But if you want to debate the merits of spreadsheets vs. databases, I'll see you on Springer.