1. What is Amazon Redshift Spectrum?
Answer: Amazon Redshift Spectrum is a feature that allows you to query and retrieve structured and semi-structured data from files in Amazon S3 without having to load the data into Amazon Redshift tables.
2. How does Redshift Spectrum perform queries?
Answer: Redshift Spectrum queries employ massive parallelism to run very fast against large datasets. Much of the processing occurs in the Redshift Spectrum layer, and most of the data remains in Amazon S3.
3. What is the benefit of using Redshift Spectrum?
Answer: Redshift Spectrum allows you to query data directly from files on Amazon S3 without having to load the data into Amazon Redshift tables. This can save time and resources, as well as enable you to query larger datasets.
4. How do you create Redshift Spectrum tables?
Answer: You create Redshift Spectrum tables by defining the structure for your files and registering them as tables in an external data catalog. The external data catalog can be AWS Glue, the data catalog that comes with Amazon Athena, or your own Apache Hive metastore.
5. Can you partition external tables in Redshift Spectrum?
Answer: Yes, you can optionally partition external tables on one or more columns. Defining partitions as part of the external table can improve performance, as the Amazon Redshift query optimizer eliminates partitions that don't contain data for the query.