AWS Glue Crawler Classifies json file as UNKNOWN

I have two json files which are 42mb and 16mb, partitioned on S3 as path:

  • s3://bucket/stg/year/month/_0.json

  • s3://bucket/stg/year/month/_1.json

I had the same problem as you, crawler classification as UNKNOWN.

I were able to solved it:

  • You must create custom classifier with jsonPath as "$[*]" then create new crawler with the classifier.
  • Run your new crawler with the data on S3 and proper schema will be created.
  • DO NOT update your current crawler with the classifier as it won't apply the change, I don't know why, maybe because of classifier versioning AWS mentioned in their documents. Create new crawler make them work