/// <summary>
        /// Stop the server upgrade.
        /// </summary>
        /// <param name="entity">The server to cancel upgrade</param>
        /// <returns>The server that was deleted</returns>
        protected override IEnumerable <AzureSqlServerUpgradeModel> PersistChanges(IEnumerable <AzureSqlServerUpgradeModel> entity)
        {
            if (!Force.IsPresent && !ShouldProcess(
                    string.Format(CultureInfo.InvariantCulture, Microsoft.Azure.Commands.Sql.Properties.Resources.StopAzureSqlServerUpgradeDescription, this.ServerName),
                    string.Format(CultureInfo.InvariantCulture, Microsoft.Azure.Commands.Sql.Properties.Resources.StopAzureSqlServerUpgradeWarning, this.ServerName),
                    Microsoft.Azure.Commands.Sql.Properties.Resources.ShouldProcessCaption))
            {
                return(null);
            }

            ModelAdapter.Cancel(this.ResourceGroupName, this.ServerName);

            return(null);
        }