If you're on AWS you can use something like Athena or you can load data from csv...

tootie 44 days ago | parent | context | favorite | on: Crunchy Bridge for Analytics: Your Data Lake in Po...

If you're on AWS you can use something like Athena or you can load data from csv/parquet in S3 into Redshift. But yeah, not directly within RDS Postgres to my knowledge.