title: How to partition data by datetime in AWS Glue?
body: <p>The current set-up:</p>
  
  <ul>
  <li><p>S3 location with json files. All files stored in the same location (no day/month/year structure).</p></li>
  <li><p>Glue Crawler reads the data in a catalog table</p></li>
  <li>Glue ETL job transforms and stores the data into parquet tables in s3</li>
  <li>Glue Crawler reads from s3 parquet tables and stores into a new table that gets queried by Athena</li>
  </ul>
  
  <p>What I want to achieve is the parquet tables to be partitioned by day (1) and the parquet tables for 1 day to be in the same file (2). Currently there is a parquet table for each json file.</p>
  
  <p>How would I go about it?</p>
  
  <p>One thing to mention, there is a datetime column in the data, but it's a unix epoch timestamp. I would probably need to convert that to a 'year/month/day' format, otherwise I'm assuming it will create a partition for each file again.</p>
  
  <p>Thanks a lot for your help!!</p>