The idea is for it to run on a daily schedule, checking if there’s any new CSV file in a folder-like structure matching the day for which the task is running. For example, if the task is running for 2010-01-31, then then it will check if there is any file in
s3://data/year=2010/month=01/day=31/*. If it finds a file there, it will add the “folder” as a partition to Athena so we can keep querying it.
Remind me again: why Athena?
At this point, if you are still wondering why Athena is so useful when you already have a pipeline in process to dump data somewhere (maybe a DB?) well, remember Athena is a “pay as you go” solution that will scale automatically for the desired queries you are running. The underlying costs are only associated with the S3 file hosting itself plus the execution of queries. Such queries, when combined with the Hive Metastore will provide a fast solution for querying heavy loads of data stored in several different types of files on an S3 bucket. On the other hand, provisioning a Database for dumping data will have fixed costs such as processing power, memory and storage amount which will surpass the first ones in case you are not using/needing the full blown features of having in place a proper database engine.
Before proceeding, there are three important assumptions: Continue reading “Build a Data Pipeline with AWS Athena and Airflow (part 2)”