Amazon Redshift
Database Developer Guide (API Version 2012-12-01)

Unloading Data

To unload data from database tables to a set of files in an Amazon S3 bucket, you can use the UNLOAD command with a SELECT statement. You can unload text data in either delimited format or fixed-width format, regardless of the data format that was used to load it. You can also specify whether to create compressed GZIP files.

You can limit the access users have to your Amazon S3 bucket by using temporary security credentials.