Column Expression: Dynamically Extract and Define Type

[mlauber71]

@mwiegand

Reason for that is that data might get shared / transmitted in human readable text files types.

If you absolutely must have text files that are still readable you could try and use the ARFF format which is also supported by KNIME

Export data from KNIME for processing in Python (externaly)

@TheLeo you could use Parquet to keep the column types. Or SQLite database: ORC could also be an option but it might be more complicated. Both ORC and Parquet would allow to read and write data in chunks. If you absolutely must have a text only file. ARFF is another option: If you want to explore more about exchange between KNIME and Python you might have a look here:

use the new (KNIME 4.6) integrated Python extension to read and write ARFF...

ARFF Format - Weka Wiki