DbProviderFactory with Npgsql?
Try defining a factory in your app.config:
<system.data> <DbProviderFactories> <add name="Npgsql Data Provider" invariant="Npgsql" description="Data Provider for PostgreSQL" type="Npgsql.NpgsqlFactory, Npgsql" /> </DbProviderFactories></system.data>Via http://fxjr.blogspot.pt/2013/06/npgsql-code-first-entity-framework-431.html
The type attribute value is important in the DbProviderFactories entry.
For me, the version number was incorrect.Correct version was :
<system.data> <DbProviderFactories> <add name="Npgsql Data Provider" invariant="Npgsql" support="FF" description=".Net Framework Data Provider for Postgresql Server" type="Npgsql.NpgsqlFactory, Npgsql, Version=2.2.3.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7" /> </DbProviderFactories></system.data>You can retrieve the value on your project with :
typeof(Npgsql.NpgsqlFactory).AssemblyQualifiedName