Use a single COPY command to load from multiple files - Amazon Redshift

Amazon Redshift will no longer support the creation of new Python UDFs starting November 1, 2025. If you would like to use Python UDFs, create the UDFs prior to that date. Existing Python UDFs will continue to function as normal. For more information, see the blog post .

Use a single COPY command to load from multiple files

Amazon Redshift can automatically load in parallel from multiple compressed data files. You can specify the files to be loaded by using an Amazon S3 object prefix or by using a manifest file.

However, if you use multiple concurrent COPY commands to load one table from multiple files, Amazon Redshift is forced to perform a serialized load. This type of load is much slower and requires a VACUUM process at the end if the table has a sort column defined. For more information about using COPY to load data in parallel, see Loading data from Amazon S3.