/// <summary>
/// Adds a column to the key for this subclass, if used
/// in a table-per-subclass strategy.
/// </summary>
/// <param name="column">Column name</param>
public void KeyColumn(string column)
{
KeyMapping key;
if (attributes.IsSpecified("Key"))
{
key = attributes.GetOrDefault <KeyMapping>("Key");
}
else
{
key = new KeyMapping();
}
key.AddColumn(Layer.UserSupplied, new ColumnMapping(column));
attributes.Set("Key", Layer.UserSupplied, key);
}