ADO.NET

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ADO.NET is a set of computer software components that can be used by programmers to access data and data services. It is a part of the base class library that is included with the Microsoft .NET Framework. It is commonly used by programmers to access and modify data stored in relational database systems, though it can also be used to access data in non-relational sources. ADO.NET is sometimes considered an evolution of ActiveX Data Objects (ADO) technology, but was changed so extensively that it can be considered an entirely new product.

This technology is a part of .NET Framework 3.0 (having been part of the framework since version 1.0)

ADO.NET and Visual Studio

Functionality exists in the Visual Studio IDE to create specialized subclasses of the DataSet classes for a particular database schema, allowing convenient access to each field through strongly-typed properties. This helps catch more programming errors at compile-time, making the IDE's Intellisense feature more beneficial.

Entity Framework

ADO.NET Entity Framework is a set of data access APIs for the Microsoft .NET Framework, similar to the Java Persistence API, targeting the version of ADO.NET that ships with .NET Framework 3.5. ADO.NET Entity Framework is included with .NET Framework 3.5 Service Pack 1 and Visual Studio 2008 Service Pack 1, released on 11 August 2008. An Entity Framework Entity is an object which has a key representing the primary key of a logical datastore entity. A conceptual Entity Data Model (Entity-relationship model) is mapped to a datastore schema model. Using the Entity Data Model, the Entity Framework allows data to be treated as entities independently of their underlying datastore representations.

Entity SQL is a SQL-like language for querying the Entity Data Model (instead of the underlying datastore). Similarly, Linq extension Linq-to-Entities provides typed querying on the Entity Data Model. Entity SQL and Linq-to-Entities queries are converted internally into a Canonical Query Tree which is then converted into a query understandable to the underlying datastore (e.g. into SQL in the case of a Relational database). The entities can be using their relationships, and their changes committed back to the datastore.

Third-party data providers

There is a wide range of data providers that are used to gain access to the database engines like Oracle, Microsoft SQL Server, MySQL, PostgreSQL, SQLite, DB2, and others:

• Connector/Net: native data provider for MySQL database server (free)
• DataDirect Connect for ADO.NET: data providers for Oracle, DB2, SQL Server, and Sybase database servers from DataDirect (commercial)
• DB2 .NET: data provider for DB2 database server from IBM (free)
• dotConnect: data providers for Oracle, MySQL, PostgreSQL, SQL Server, and SQLite database servers from Devart (free and commercial)
• Npgsql: open source data povider for PostgreSQL database server (free)
• Oracle Data Provider for .NET (ODP.NET): data provider for Oracle database server from Oracle (free)
• VistaDB: 100% managed ADO.NET provider with SQL Server like syntax
• RDM Server: data povider for the RDM Server database system from Birdstep Technology, Inc (free)

See also

External links