column pruning inside transform UDF
I have UDF transform function to map one string serialized column into many regular columns. It takes serialization schema and extracts attributes according to it. The problem is when I get just a single attribute out of serialized string UDF still extracts all of them according to schema and only after that vertica drops unused columns.
Is it possible to programmatically get the list of columns really used in a query so I can perform column pruning inside my UDF?