namespace ModuleName
{
	public class Migrations : DataMigrationImpl
	{
		public int Create()
		{
			return 1;
		}

		public int UpdateFrom1()
		{
			return ExecuteUpdateFrom(1);
		}

		public int UpdateFrom2()
		{
			return ExecuteUpdateFrom(2);
		}

		/// <summary>
		/// Execute the update migration step.
		/// </summary>
		/// <param name="updateFrom">Current migration step.</param>
		/// <param name="nextVersion">Next migration step. Specify null if the next step is the increment of 'updateFrom'.</param>
		/// <returns>The next migration step.</returns>
		private int ExecuteUpdateFrom(int updateFrom, int? nextVersion = null)
		{
			SomeRecord.UpdateFrom(updateFrom, SchemaBuilder, ContentDefinitionManager);

			return nextVersion ?? (updateFrom + 1);
		}
	}
}


public class SomeRecord : AbstractRecord
{
	public virtual int Id { get; set; }

	/// <summary>
	/// Perform migration.
	/// </summary>
	/// <param name="curVersion">Version to upgrade from.</param>
	/// <param name="schemaBuilder">Schema builder.</param>
	/// <param name="contentDefinitionManager">Content definition manager.</param>
	internal static void UpdateFrom(int curVersion, SchemaBuilder schemaBuilder, IContentDefinitionManager contentDefinitionManager)
	{
		switch (curVersion)
		{
			case 1:
			{
				schemaBuilder.CreateTable(typeof(SomeRecord).Name, table => table
					.IndexColumn()
				);

				break;
			}
			case 2:
			{
				// Do nothing.. case isn't really needed either
				break;
			}
		}
	}
}