BetterMembership.Web.BetterMembershipProvider.CreateUserEmailColumn C# (CSharp) Метод

        private void CreateUserEmailColumn()
        {
            using (var db = this.ConnectToDatabase())
            {
                if (!db.ColumnExists(this.UserTableName, this.UserEmailColumn))
                {
                    if (this.RequiresUniqueEmail)
                    {
                        if (
                            !db.AddColumnToTable(
                                this.UserTableName, 
                                this.UserEmailColumn, 
                                SqlDbType.NVarChar, 
                                this.MaxEmailLength, 
                                false, 
                                true))
                        {
                            db.AddColumnToTable(
                                this.UserTableName, 
                                this.UserEmailColumn, 
                                SqlDbType.NVarChar, 
                                this.MaxEmailLength, 
                                true, 
                                false);
                        }
                    }
                    else
                    {
                        db.AddColumnToTable(
                            this.UserTableName, 
                            this.UserEmailColumn, 
                            SqlDbType.NVarChar, 
                            this.MaxEmailLength, 
                            false, 
                            false);
                    }
                }
            }
        }