Sometimes we quickly need to check the schema of a parquet file, or to head the parquet file for some sample records.
Here are some straight ways by which you could check the contents of a parquet file from local or S3/ HDFS.
Get the parquet-tools jar
- Download jar, or
- Build jar
Download the jar from maven repo, or any location of your choice. Just google it. The time of this post I can get the parquet-tools from here.
If you’re logged in the hadoop box:
This link might stop working few days later. So get the new link from maven repo.
If you are unable to download the jar, you could also build the jar from source. Clone the parquet-mr repo and build the jar from the source
git clone https://github.com/apache/parquet-mr
mvn clean package
Note: you need maven on your box to build the source.
Read parquet file
You can use these commands to view the contents of the parquet file-
Check schema for s3/hdfs file:
hadoop jar parquet-tools-1.9.0.jar schema s3://path/to/file.snappy.parquet
hadoop jar parquet-tools-1.9.0.jar schema hdfs://path/to/file.snappy.parquet
Head file contents:
hadoop jar parquet-tools-1.9.0.jar head -n5 s3://path/to/file.snappy.parquet
Check contents of local file:
java -jar parquet-tools-1.9.0.jar head -n5 /tmp/path/to/file.snappy.parquet
java -jar parquet-tools-1.9.0.jar schema /tmp/path/to/file.snappy.parquet
hadoop jar parquet-tools-1.9.0.jar –help
Hope it is helpful.
Yash Sharma is a Big Data & Machine Learning Engineer, A newbie OpenSource contributor, Plays guitar and enjoys teaching as part time hobby.
Talk to Yash about Distributed Systems and Data platform designs.