Microsoft SQL Server

Microsoft SQL Server is a relational database management system developed by Microsoft. As a database server, it is a software product with the primary function of storing and retrieving data as requested by other software applications—which may run either on the same computer or on another computer across a network (including the Internet).

Microsoft markets at least a dozen different editions of Microsoft SQL Server, aimed at different audiences and for workloads ranging from small single-machine applications to large Internet-facing applications with many concurrent users.

The history of Microsoft SQL Server begins with the first Microsoft SQL Server product - SQL Server 1.0, a 16-bit server for the OS/2 operating system in 1989 - and extends to the current day.

As of December 2016^[update] the following versions are supported by Microsoft:

The current version is Microsoft SQL Server 2016, released June 1, 2016. The RTM version is 13.0.1601.5.

SQL Server 2016 is supported on x64 processors only.

Microsoft makes SQL Server available in multiple editions, with different feature sets and targeting different users. These editions are:

The protocol layer implements the external interface to SQL Server. All operations that can be invoked on SQL Server are communicated to it via a Microsoft-defined format, called Tabular Data Stream (TDS). TDS is an application layer protocol, used to transfer data between a database server and a client. Initially designed and developed by Sybase Inc. for their Sybase SQL Server relational database engine in 1984, and later by Microsoft in Microsoft SQL Server, TDS packets can be encased in other physical transport dependent protocols, including TCP/IP, named pipes, and shared memory. Consequently, access to SQL Server is available over these protocols. In addition, the SQL Server API is also exposed over web services.