Microsoft SQL Server Express is a version of Microsoft's SQL Server relational database management system that is free to download, distribute and use. It comprises a database specifically targeted for embedded and smaller-scale applications. The product traces its roots to the Microsoft Database Engine (MSDE) product, which was shipped with SQL Server 2000. The "Express" branding has been used since the release of SQL Server 2005. Microsoft SQL Server Express LocalDB is a version of Microsoft SQL Server Express, on-demand managed instance of the SQL Server engine. It is targeted to developers, and has the following restrictions: up to 10 GB database size and only local connections (network connections are not supported).

Capabilities

SQL Server Express provides many of the features of the paid, full versions of Microsoft SQL Server database management system. However it has technical restrictions that make it unsuitable for some large-scale deployments. Differences in the Express product include: Unlike the predecessor product, MSDE, the Express product does not include a concurrent workload-governor to "limit performance if the database engine receives more work than is typical of a small number of users." SQL Server Express includes several GUI tools for database management. These include: The predecessor product MSDE generally lacked basic GUI management tools, Features available in SQL Server "Standard" and better editions but absent from SQL Server Express include:

LocalDB

SQL Server Express LocalDB announced at 2011. This version supports silent installation, requires no management and it is compatible with other editions of SQL Server at the API level. LocalDB runs as non-admin user, requires no configuration or administration. LocalDB limits to local system only and supports no remote connections. To connect this version it is needs special connection string. It is possible create several instances of the LocalDB for different applications. Default instance names 'SqlLocalDB'.

Variants

Microsoft makes SQL Server Express N1 available as: In the Free 2005 Express version, for example, a standard approach to installation options was provided, as follows. Generally, the SQL 2005 Express installers are packaged with the following consistent naming convention: These optional variants have gone through several service packs (SP), and each SP installer can be used without using the older ones first:

Version history