![]() For example, to load data from Amazon S3, COPY must have LIST access to the bucket and. To move data between your cluster and another AWS resource, such as Amazon S3, Amazon DynamoDB, Amazon EMR, or Amazon EC2, your cluster must have permission to access the resource and perform the necessary actions. ![]() Of course, this workaround assumes that no other parameters would be bound outside of the UNLOAD's query inside the ( ). Permissions to access other AWS Resources. The Redshift IAM role must have access to the KMS key for writing with it, and the Spark IAM role must have access to the key for read operations. unload (' SELECT col1, col2, col3, currentdate as partitionbyme FROM dummy ' ) to 's3://mybucket/dummy/' partition by (partitionbyme) iamrole 'arn of IAM role' kmskeyid 'arn of kms key' encrypted FORMAT AS. Subsequently, if the sub-query executed successfully without any errors or exceptions, we could assume that the sub-query is safe, thus allowing us to wrap the sub-query back into the UNLOAD parent statement, but this time replacing the bind parameters with actual user-supplied parameters (simply concatenating them), which have now been validated in the previously run SELECT query. The AWS KMS key ID to use for server-side encryption in S3 during the Redshift UNLOAD operation rather than the AWS default encryption. Redshift unload gives an option to load the data in a by partition. This would let us use Redshift's prepared statement support (which is indeed supported for SELECT queries) to bind and validate the potentially risky, user-supplied parameters first. While trying to devise a workaround for this, a colleague of mine has thought up a workaround: instead of binding the parameters into the UNLOAD query itself (which is not supported by Redshift), we could simply bind them to the inner sub-query inside the UNLOAD's ( ) first (which happens to be a SELECT query - which is probably the most common subquery used within UNLOAD statements by most Redshift users, I'd say) and run this sub-query first, perhaps with a LIMIT 1 or 1=0 condition, to limit its running time. unload ( 'select from lineitem' ) to 's3://mybucket/lineitem/' iamrole 'arn:aws:iam::0123456789012:role/MyRedshiftRole' PARQUET PARTITION BY (lshipdate) INCLUDE In these cases, the lshipdate column is also in the data in the Parquet files. Thanks for your quick reply, and thanks for re-raising this issue with the Redshift server team. In some cases, the UNLOAD command used the INCLUDE option as shown in the following SQL statement.
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