Structured Query Language (SQL) is often thought of as a database, though SQL databases actually do not exist. Rather, SQL speaks with and manages databases connected to the SQL. The two cannot function independently, so the term "SQL database" is an easier way to think of the relationship. SQL controls databases through queries and commands, and these databases are commonly used by businesses and websites.
SQL was first created by IBM® in the 1970s. The language itself was about the same then as it is in the early 21st century, but it wasn’t called SQL initially. In the beginning, it was called Structured English Query Language, or SEQUEL. Many companies have since created their own SQL databases.
SQL databases are not static entities in which data are stored and archived. Through the use of simple commands or queries, SQL databases can be instantly updated. When attached to a rapidly evolving entity, such as a website, the database will typically go through many changes in less than a day. This allows programmers to constantly fill the database without the need to create separate databases for each day or each change.
Not only can data be added to an SQL database, but data within the database can be modified. For example, if a business record is incorrectly spelled or is attached to the wrong figure, an insert query can be used to insert a new value into the database. An update query also can be used to update the information in the database. If information is completely wrong or obsolete, it is also possible to delete data from the database.
Aside from storing and updating information, another important function of an SQL database is the ability to retrieve the information. Just like all the other functions, this is done through a query that prints the information to a separate document. Data can be retrieved based on search tags or how it relates to other information in the database.
When attached to a business, SQL databases typically store both public and private information. Public information would include current prices or the names of products or services currently sold. Private information would include research and statistics being used to update products or create new products. Business databases can also be used to hold information on employees.
SQL databases are often used for websites. When a new member signs up to a website, its SQL database is updated with the member’s name and information. If sales are made, some websites use an SQL database to keep track of all sales and orders.