DbProviderFactories
Applies to: 
.NET Framework
.NET
.NET Standard
The System.Data.Common namespace provides classes for creating DbProviderFactory instances to work with specific data sources. When you create a DbProviderFactory instance and pass it information about the data provider, the DbProviderFactory can determine the correct, strongly typed connection object to return based on the information it has been provided.
The data provider Microsoft.Data.SqlClient is no longer listed in machine.config file, but custom providers will continue to be listed there.
In this section
Obtain a SqlClientFactory
Demonstrates how to obtain a SqlClientFactory from the DbProviderFactories class to work with specific data sources in .NET.