Data Resource - Virtual Columns
About
virtual columns are columns that contains generated data by data supplier.
Usage
They are most used to:
- add data attributes from the data resource such as its name, its size or its count (via with the meta supplier)
- or to compute expression with the expression data supplier
How to add virtual columns?
Tabulify permits to add virtual columns with:
- the enrich_operation
- the virtual-column tabul option.
Enrich Operation
Enrich is a intermediate pipeline operation that accepts all data suppliers as value source.
virtual-column tabul option
The virtual-column tabul option is a short cut to add a virtual column based only on the meta supplier
The syntax is the following:
--virtual-column "virtualColumnName=dataResourceAttributeName"
where:
- virtualColumnName is the name of the column added
- dataResourceAttributeName is the name of data resource attribute.