How to decode base64 to text in AWS Athena
Decoding base64 in AWS Athena requires two steps. First, we have to use the from_base64
function to get a binary representation of the decoded content. We don’t get text automatically because we can use base64 to encode as a string any binary data, for example, a picture.
Therefore, Athena does not know that the content is a string. Because of that, we have to use the from_utf8
function to convert the binary data into text.
The complete SQL looks like this:
1
select from_utf8( from_base64(base64_encoded_column) ) FROM some_table
One more thing. Never, ever say that base64 is encryption. It is not. That is just a method of representing binary data as a string, so you can send it to/from a REST API as a JSON object or include it in an URL.
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Bartosz Mikulski
- Data/MLOps engineer by day
- DevRel/copywriter by night
- Python and data engineering trainer
- Conference speaker
- Contributed a chapter to the book "97 Things Every Data Engineer Should Know"
- Twitter: @mikulskibartosz