This class describes an equality relation between two columns in different tables. A relation like '[Tbl1].[Column1] = Upper([Tbl2].[Column1])' is defined using two expressions '[Tbl1].[Column1]' and 'Upper([Tbl2].[Column1])'. These expressions are evaluated in the different source tables, so if one of the tables are external then you can use the methods provided by that external data source and if the table is not external then you can use the standard Spotfire expression language functions. Additionally you can also provide left and right transform expressions which are evaluated on top of the left/right expressions supporting all standard Spotfire expression language functions. These expression refer to the result of the corresponding expression using the name ValueColumnName. For example you need to perform "Upper" on Tbl2 but the external system doesn't support that method you can define left and right expressions like '[Tbl1].[Column1]' and '[Tbl2].[Column1]' but add additional transform expressions like '[Value]' and 'Upper([Value])'.

[ImmutableAttribute]
public sealed class ColumnRelation