How to automatically scan the entire file before executing the File Reader node

KNIME Analytics Platform
1

Hi,
I want to know if there is a method fo automatically scan the file to read before executing the FileReader node. Cause I have noticed that if I just execute it it thrown an error during the reading. But if I click on “Scan” within the node then it reads it without thrown any errors.

If for example I want to load a workflow “not manually” it will obviously thrown an error without the complete “Scan” button clicked on that node.

Any suggestions?

2

Hi @gujodm,

indeed, it should work without a need to re-scan on each new file. I’ve tried to reproduce your problem, but it seems to work in my tests out-of the box. Would it be possible for you to share a minimal reproducible example workflow? This would help me to understand what is going on and how to resolve the problem.

Best regards,
Misha

2 Likes
3

Hi @gujodm ,

did you find a solution in the meantime? If not, could you share an example as suggested above?

Have a nice weekend,
Misha

4

Hi @lisovyi, unfortunately no.
I cannot reproduce the exact problem and send an example of workflow because the csv files that I’m trying to read are too much pretty big as size.

Maybe I can try to upload them somewhere and then you can try to executed them simply with Reader node. You could obviously notice that if you just run it thrown an error. But if we make the complete scan in the option of the node before execute it then it works.

~g

5

Does it happen only for huge file size? Maybe you can strip off only first ~5-10 rows in each file? And just use 2 and not many file?

6

This topic was automatically closed 182 days after the last reply. New replies are no longer allowed.