Excel file reading in a loop changes data type

I am reading all sheets present in an excel file. Talking about a specific column that represents percentage as a datatype. But while reading in a loop that file, some sheets changes datatype to string while some change to percentage datatype. What is the issue? Can anyone please help me?


Hi @jamalbutt1232,

If you are using KNIME 4.4 you are able to read all excel files located in one directory at once:

Then you can use the transform tab to set the types of the data for the columns for all the files:


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Thank you. I will check this out. But let’s say if I want to read files using a loop because sometimes I specifically don’t want to read all sheets but want to read based on a condition. How can I then deal with the data types issue?

I see, so for example, you only want to read from files that contain a sheet with a specific name?

If you use the new Excel Reader (not the deprecated one you are using in your screenshot) you can enforce the types for all read files in a loop.



Without seeing the original data it’s difficult to say what the issue is.

Regardless, there is no percentage datatype in KNIME, and I’m guessing the problem lies in the way the values are represented in your Excel worksheets.

Got it thanks. One last thing, with the new node is there any way to read all sheets inside of our excel workbook?

Hello @jamalbutt1232,

No. You need to use loop. However there is ticket for it and will add +1. (Internal reference: AP-16419) In case of any news someone will update this topic.


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