Custom Database Provider Factory

ConfigurableSqlClientFactory

using System.Data;
using System.Data.Common;
using System.Data.Sql;
using System.Data.SqlClient;
using System.Reflection;
using System.Security;
using System.Security.Permissions;

namespace CustomSqlProvider
{
    public class ConfigurableSqlClientFactory : DbProviderFactory 
    {
        public static readonly ConfigurableSqlClientFactory Instance = new ConfigurableSqlClientFactory();

        public override bool CanCreateDataSourceEnumerator
        {
            get { return true; }
        }

        static ConfigurableSqlClientFactory()
        {
        }

        private ConfigurableSqlClientFactory()
        {
        }

        public override DbCommand CreateCommand()
        {
            var sqlCommand = new SqlCommand {CommandTimeout = 500};
            return sqlCommand;
        }

        public override DbCommandBuilder CreateCommandBuilder()
        {
            return new SqlCommandBuilder();
        }

        public override DbConnection CreateConnection()
        {
            return new ConfigurableSqlConnection();
        }

        public override DbConnectionStringBuilder CreateConnectionStringBuilder()
        {
            return new SqlConnectionStringBuilder();
        }

        public override DbDataAdapter CreateDataAdapter()
        {
            return new SqlDataAdapter();
        }

        public override DbParameter CreateParameter()
        {
            return new SqlParameter();
        }

        public override CodeAccessPermission CreatePermission(PermissionState state)
        {
            return new SqlClientPermission(state);
        }

        public override DbDataSourceEnumerator CreateDataSourceEnumerator()
        {
            return SqlDataSourceEnumerator.Instance;
        }
    }
}

ConfigurableSqlConnection

using System.Data;
using System.Data.Common;
using System.Data.Sql;
using System.Data.SqlClient;
using System.Reflection;
using System.Security;
using System.Security.Permissions;

namespace CustomSqlProvider
{
    public class ConfigurableSqlConnection : DbConnection
    {
        private readonly SqlConnection _connection;

        public ConfigurableSqlConnection()
        {
            this._connection =
                (SqlConnection)DbProviderFactories.GetFactory("System.Data.SqlClient").CreateConnection();
        }

        protected override DbTransaction BeginDbTransaction(IsolationLevel isolationLevel)
        {
            return this._connection.BeginTransaction();
        }

        public override void Close()
        {
            this._connection.Close();
        }

        public override void ChangeDatabase(string databaseName)
        {
            this._connection.ChangeDatabase(databaseName);
        }

        public override void Open()
        {
            this._connection.Open();
        }

        public override string ConnectionString
        {
            get { return this._connection.ConnectionString; }
            set { this._connection.ConnectionString = value; }
        }

        public override string Database
        {
            get { return this._connection.Database; }
        }

        public override ConnectionState State
        {
            get { return this._connection.State; }
        }

        public override string DataSource
        {
            get { return this._connection.DataSource; }
        }

        public override string ServerVersion
        {
            get { return this._connection.ServerVersion; }
        }

        protected override DbCommand CreateDbCommand()
        {
            var dynMethod = this._connection.GetType()
                .GetMethod("CreateDbCommand", BindingFlags.NonPublic | BindingFlags.Instance);

            var dbCommand = (SqlCommand)dynMethod.Invoke(this._connection, new object[] { });
            dbCommand.CommandTimeout = 500;
            return dbCommand;
        }
    }
}