The expression transformation allows adding, replacing and/or deleting columns. This is generally done by supplying a column selection to work on and in the first two cases an expression, name and optionally formatter to replace it with. The column selection can either be a fixed set of columns or a column search expression that will be reevaluated each time the transformation is executed. To be able to refer to the columns selected in expressions use the column name symbol.

[SerializableAttribute]
[PersistenceVersionAttribute(3, 0)]
public sealed class ExpressionTransformation : DataTransformation