Structured Query Language (SQL)

What is Structured Query Language (SQL)?

SQL (Structured Query Language) is a standard programming language used for managing and manipulating relational databases.

A relational database is a type of database management system (DBMS) that stores data in the form of related tables. Each table in a relational database represents a different type of data, and the tables are related to each other through a set of defined relationships.

SQL is used to insert, update, delete, and query data stored in a database.

SQL is a declarative language, which means that you specify what you want the database to do, and the database management system figures out how to do it. For example, you can use SQL to query a database and retrieve a specific set of data, or to insert new data into a table.

SQL is composed of several different types of statements, including:

  • SELECT: used to retrieve data from one or more tables in a database.
  • INSERT: used to insert new data into a table.
  • UPDATE: used to modify existing data in a table.
  • DELETE: used to delete data from a table.
  • CREATE: used to create new tables, views, or other database objects.
  • DROP: used to delete existing tables, views, or other database objects.
  • ALTER: used to modify the structure of existing tables or other database objects.

SQL is used by many relational database management systems, including MySQL, MariaDB, Oracle Database, Microsoft SQL Server, and PostgreSQL, among others.

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