Hi Harika,
You might want to import just one ZIP file with many .xlsx files inside.
Warning: You cannot replace a subset of files that were uploaded as a single .zip file. The whole .zip file must be replaced.
You will find the requirement for size limits in here: https://www.ibm.com/docs/en/cognos-analytics/12.0.0?topic=uf-requirements-uploaded-files
Best regards,
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Patrick Neveu
Collaboration Betters The World (CBTW)
IBM Champion
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