You can save almost 90% on your query costs by compressing, partitioning, and converting your data into columnar formats. This will also increase the performance. Each of these operations reduces the amount of data Amazon Athena needs to scan to execute a query. Amazon Athena supports Apache Parquet and ORC, two of the most popular open-source columnar formats. You can see the amount of data scanned per query, on the Athena console.
Basically compressing and partitioning are the methods one should follow to reduce the billing amount. There is another method but not always effective i.e. Converting it into Columnar formats.
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