@Genentech I am not sure if this is the answer you are looking for, but my recommendation is to leave your original table as is and select results from that into the parquet table. I am a firm believe of using backup copies, staging, copies or temporary copies of original data sources on the path through translation to final source.
Make a new empty table with the parquet format you want. The format must match. Next execute:
INSERT INTO final_table SELECT * from source_table;
If you need to retain the same original table name, you can alter or drop the original table, and execute a rename statement on the final_table above.
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