What Is SQL?

SQL, Structured Query Language, is the standard language used to communicate with a relational database.

What Is a Database?

In very simple terms, a database is a collection of data. Some like to think of a database as an organized mechanism that has the capability of storing information, through which a user can retrieve stored information in an effective and efficient manner.

People use databases every day without realizing it. A phone book is a database. The data contained consists of individuals' names, addresses, and telephone numbers. The listings are alphabetized or indexed, which allows the user to reference a particular local resident with ease. Ultimately, this data is stored in a database somewhere on a computer. After all, each page of a phone book is not manually typed each year a new edition is released.

The database has to be maintained. As people move to different cities or states, entries may have to be added or removed from the phone book. Likewise, entries will have to be modified for people changing names, addresses, or telephone numbers, and so on.

A relational database is a database divided into logical units called tables, where tables are related to one another within the database. A relational database allows data to be broken down into logical, smaller, more manageable units, allowing for easier maintenance and providing more optimal database performance according to the level of organization.