SQL is a standardized query language for requesting information from a database. It is an abbreviation for structured query language and is pronounced as separate letters, although some users pronounce it see-kwell.
History of SQL
The original version, called SEQUEL (structured English query language), was designed by an IBM research center in 1974 and 1975. SQL was first introduced as a commercial database system in 1979 by Relational Software, which later became Oracle.
Before SQL, databases used the CODASYL (the Conference/Committee on Data Systems Languages) system to retrieve data. Searching for data using CODASYL’s method required more steps, but it also took less computer memory and time than SQL to return a query. Some professionals believe that SQL, though the standard language for databases, is not the best possible solution. However, it’s by far the most well known.
Historically, SQL has been the favorite query language for database management systems running on minicomputers and mainframes. Increasingly, however, SQL is being supported by PC database systems because it supports distributed databases (databases that are spread out over several computer systems). This enables multiple users on a local-area network to access the same database simultaneously.
SQL originated in relational databases. In a relational database, pieces of data are stored by their relationship to each other, in tables and columns. In 1986, ANSI approved a rudimentary version of SQL as the official standard, but most versions of SQL since then have included many extensions to the ANSI standard. In 1991, ANSI updated the standard. The new standard is known as SAG SQL. Not all database software or engines have incorporated all of the aspects of the standard, either; their developers tend to pick and choose which features and extensions they want to use.
How SQL works
SQL allows the storage and retrieval of data within a very large database. Business applications have to draw from an enormous storehouse of data to run efficiently and pull information quickly. Users make commands to create and delete tables and elements within tables. Database keys are used as labels or tags for each piece of data or cell within a table; they can also be used to connect separate tables or elements in a table.
Users begin a query with the SELECT command. They then add the queries they need to search data within the database. That could include a small range (such as records of customers with the last name Smith) or an entire table. Typically, the more data a user queries, the longer it takes SQL to retrieve it.
A few of the most popular and well-known SQL software or database services include:
UPDATED: This article was updated April 2, 2021 by Web Webster.