SQL
Structured Query Language
SQL is the acronym for Structured Query Language.
A programming language specifically designed for managing and manipulating relational databases. SQL provides a standardized way to interact with databases, allowing users to create, retrieve, update, and delete data.
SQL is used to communicate with a database management system (DBMS) responsible for storing and organizing data. The most commonly used DBMS that supports SQL is called a relational database management system (RDBMS). Examples of popular RDBMSs include MySQL, PostgreSQL, Oracle, Microsoft SQL Server, and SQLite.
With SQL, you can perform various operations on a database, including:
- Creating databases, tables, and views: SQL allows you to define the structure of a database by creating databases to store related information, tables to organize data into rows and columns, and views to create virtual representations of data based on queries.
- Querying and retrieving data: You can use SQL to retrieve specific data from one or more tables by using SELECT statements. SQL provides powerful filtering, sorting, and grouping capabilities to retrieve the desired information.
- Inserting, updating, and deleting data: SQL allows you to add new records to a table using INSERT statements, modify existing records using UPDATE statements, and remove unwanted records using DELETE statements.
- Defining relationships and constraints: SQL provides mechanisms to establish relationships between tables using primary and foreign keys. You can enforce data integrity rules and constraints, such as uniqueness, referential integrity, and data type constraints.
- Performing calculations and aggregations: SQL includes various functions and operators to perform calculations and aggregations on data. These include mathematical operations, string manipulation, date/time functions, and aggregate functions like SUM, AVG, COUNT, MAX, and MIN.
SQL is a versatile language offering a wide range of capabilities for databases. It is widely used in data management and essential for developers, analysts, and administrators working with relational databases.
- Abbreviation: SQL