How to append dataframe to xlsx file without loading workbook? - python

I'm working with slightly big data and i need to write this data to an xlsx file. Sometimes the size of this files can be 15GB. I have a python code that gets data as dataframes and writes data to excel continuously so i need to write data to an existing excel and the existing sheet. I was using 'openpyxl'.
There are two problems that I faced while working with that library.
Firstly to append an existing excel it needs to load workbook which is an impossible thing for me because of the data size. I must use
the lowest RAM I can use. -
Secondly this lib is useful only writing
to the different sheets. When I'm trying to write data to same sheet
even if I give the 'startrow' for the saving process it deletes the
old data and writes new one starting from that row.
I already tried the solution available here to address my problem but it doesn't fit my requirements.
Do you have any idea how I can do this?.

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The question is pretty simple, actually.
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Be careful not to over-engineer, that being said:
Depending on your use case, if this is really needed, I could theoretically imagine a Robotic Process Automation like e.g. BluePrism, UiPath or PowerAutomate loading live data from Excel into a Python environment with a pandas DataFrame continuously and then changing it.
This use case would have to be a really important process though, otherwise licensing RPA is not worth it here.
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For example:
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Here's the example spreadsheet: download

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