Convert Parquet file to CSV using NiFi

@Gubbi 

The solution you are looking for is ConvertRecord + ParquetRecordReader + CSVRecordWriter.  The ParquetRecordReader is included in NiFi 1.10 and up.  If you have an older nifi, here is a post where I talk about adding the required jar files to nifi 1.9 (older version doesn't have parquet):

https://community.cloudera.com/t5/Support-Questions/Can-I-put-the-NiFi-1-10-Parquet-Record-Reader-in-NiFi-1-9/td-p/286465

Another suggestion: If you are working with nifi and hadoop/hdfs/hive,  you could store the raw parquet, create external hive table on parquet, then select results and insert them into similar table of csv format.  Then you select the csv table results and create csv file. 

Also in order to validate/inspect your parquet, or to read the schema (if you need it for controller services) you use parquet tools:  

https://community.cloudera.com/t5/Community-Articles/Build-and-use-Parquet-tools-to-read-parquet-files/ta-p/248629

If this answer resolves your issue or allows you to move forward, please choose to ACCEPT this solution and close this topic. If you have further dialogue on this topic please comment here or feel free to private message me. If you have new questions related to your Use Case please create separate topic and feel free to tag me in your post.  

Thanks,

Steven @ DFHZ