Hello @Parthivelu ,
Thanks for question and also for using this new forum .
I am not sure if you have gone through this link , there are some limitation of copy activity when handling paraquet file .
https://learn.microsoft.com/en-us/azure/data-factory/format-parquet#data-type-support . May be you have this issue .
"Parquet complex data types (e.g. MAP, LIST, STRUCT) are currently supported only in Data Flows, not in Copy Activity"
Thanks Himanshu
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