I m trying to convert my data layer from Linq2Sql to nHibernate. I think Xml the configuration in nHibernate is pretty backwards so I m using Fluent.

I ve managed to get fluent, add in a repository pattern and unit of work pattern, and my unit tests are looking good.

However now as I m plugging it into my services layer I m noticing that each time I run my app the database gets recreated.

I am guessing this is down to my SessionProvider code, I m not sure of all the extensions I m using. Can someone shed some light on how to stop this from happening?

public sealed class SessionProvider
{
    private static ISessionFactory _sessionFactory;

    private static ISessionFactory CreateSessionFactory()
    {
        try
        {
            return Fluently.Configure()
                .Database(MsSqlConfiguration.MsSql2005
                              .ConnectionString(Properties.Settings.Default.DBConnection)
                              .Cache(c => c
                                              .UseQueryCache()
                                              .ProviderClass<HashtableCacheProvider>())
                              //.ProxyFactoryFactory("NHibernate.ByteCode.Castle.ProxyFactoryFactory,NHiber nate.ByteCode.Castle")
                              .ShowSql())
                              .Mappings(m=>m.FluentMappings.AddFromAssembly(Assembly.GetExecutingAssembly()))
                .ExposeConfiguration(BuildSchema)
                .BuildSessionFactory();
        }
        catch (Exception ex)
        {
            System.Diagnostics.Debug.WriteLine(ex.Message);
            return null;
        }


    }

    public static ISessionFactory SessionFactory
    {
        get
        {
            if (_sessionFactory == null)
            {
                _sessionFactory = CreateSessionFactory();
            }
            return _sessionFactory;
        }
    }

    public static ISession GetSession()
    {
        return SessionFactory.OpenSession();
    }

    private static void BuildSchema(Configuration config)
    {
        // this NHibernate tool takes a configuration (with mapping info in)
        // and exports a database schema from it
        new SchemaExport(config).Create(false, true);
    }
}