ADO.NET Data Providers
The classes responsible for the movement of data between the
disconnected data classes in the client application and the data store are
referred to as connected classes or provider classes.
The ADO.NET Framework comes with the following providers:
- OLEDB: The OLEDB provider, expressed through the System.Data.OleDb namespace. You
can use this provider to access SQL Server 6.5 and earlier, SyBase, DB2/400,
and Microsoft Access.
- ODBC: The ODBC provider, expressed through the System.Data.Odbc namespace. This
provider is typically used when no newer provider is available.
- SQL Server: The Microsoft SQL Server provider, expressed through the System.Data.SqlClient namespace. It Contains
classes that provide functionality similar to the generic OleDb provider. The difference is that these classes are
tuned for SQL Server 7 and later data access.
Prior to .NET Framework 4, Microsoft also included a functional Oracle
provider with the .NET Framework. However, its classes have been marked as
deprecated and obsolete in .NET Framework 4.
Core objects that
make up a .NET Framework data provider:
- Connection : Establishes a connection to a specific data source.
The base class for all Connection objects is the DbConnection
class.
- Command : Executes a command against a data source. Exposes Parameters and can execute in the scope of a Transaction from a Connection. The
base class for all Command objects is the DbCommand
class.
- DataReader : Reads a forward-only, read-only stream of data from a
data source. The base class for all DataReader objects
is the DbDataReader class.
- DataAdapter : Populates a DataSet and
resolves updates with the data source. The base class for all DataAdapter objects is the DbDataAdapter class.
In addition to the
core classes .NET Framework data provider also contains the classes Transaction, CommandBuilder, ConnectionStringBuilder,
Parameter, Exception, Error and ClientPermission