SQL Server

SQL Server
Name	SQL Server
Developer	Microsoft
Released	24 April 1989
Latest release version	SQL Server 2022
Operating system	Microsoft Windows, Linux
Genre	Relational database management system

SQL Server. It is a relational database management system developed by Microsoft. As a core component of the Microsoft data platform, it provides a comprehensive environment for storing, processing, and securing data. It is widely used across various industries to support applications ranging from small websites to large-scale enterprise systems.

Overview

This platform serves as a foundational data management and analysis engine. It integrates with other Microsoft technologies like the .NET Framework and Power BI to provide a cohesive application development and business intelligence stack. Major versions, such as SQL Server 2019 and SQL Server 2022, have introduced significant capabilities in areas like big data and artificial intelligence. The system is engineered for high availability and performance, supporting mission-critical workloads for organizations globally.

History

The origins trace back to a partnership between Microsoft and Sybase in the late 1980s, resulting in the first release for OS/2. After the collaboration ended, Microsoft independently developed subsequent versions. Key milestones include the release of SQL Server 7.0, which was a major code rewrite, and SQL Server 2005, which introduced foundational modern features like Common Language Runtime integration. The platform's evolution has been marked by integration with the Windows Server ecosystem and, more recently, expansion to Linux and Docker containers.

Editions and features

It is offered in several editions to cater to different needs, from the free Express Edition to the comprehensive Enterprise Edition. The Developer Edition provides full functionality for building and testing applications. Core features across editions include the Database Engine, Analysis Services for OLAP, and Integration Services for ETL processes. Advanced editions offer features like PolyBase for querying external data sources, Machine Learning Services with R and Python, and sophisticated tools for data warehousing.

Architecture

The core component is the Database Engine, which handles data storage, processing, and security. It uses a relational engine for query processing and a storage engine for managing data files, log files, and in-memory OLTP structures. The platform supports clustered indexes and nonclustered indexes for data retrieval optimization. For high availability, it employs technologies like Always On Availability Groups and Failover Cluster Instances. The architecture also encompasses columnstore indexes for analytical workloads.

Tools and management

Primary administration and development is performed through SQL Server Management Studio, a central tool for configuring, monitoring, and managing instances. Azure Data Studio provides a modern, cross-platform editor for data professionals. Other key tools include SQL Server Data Tools for database development within Visual Studio and SQL Server Configuration Manager. For performance tuning, administrators use Dynamic Management Views and the Query Store to diagnose and resolve issues.

Security

The platform provides a multi-layered security model. It employs authentication via Windows Authentication or SQL Server Authentication, and authorization through a granular permissions system using principals, securables, and permissions. Data protection features include Transparent Data Encryption, Always Encrypted for column-level security, and Dynamic Data Masking. It also integrates with Azure Active Directory and offers robust auditing capabilities to meet compliance standards for regulations like GDPR and HIPAA.

Data types and querying

It supports a wide range of system-supplied data types, including exact numerics like INT and DECIMAL, approximate numerics like FLOAT, character strings like VARCHAR, and date/time types like DATETIME2. Specialized types include XML, JSON, and spatial data types for geometry and geography. Data is queried and manipulated primarily using Transact-SQL, the proprietary extension to SQL that adds procedural programming, local variables, and support for error handling.

Category:Microsoft database software Category:Relational database management systems