---
schema_version: "1"
id: 9df2d74994494bba74658a98cf29d2b24de6b1c7a9bb1f851d98a403a16ef6a8
title: Import or Copy Large Datasets
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/mktg/264-0-0/mc_as_data_copy_or_import.md
canonical_url: https://help.salesforce.com/s/articleView?id=mktg.mc_as_data_copy_or_import.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: 2c6122a21dc80b81aa6a73389237d81af5deeb4619f00b14c41352a2f7da4477
description: When transferring a large dataset from an external file or a data extension, use the Data Copy or Import activity to help prevent data loss, minimize downtime, and maintain business continuity. With the Data Copy or Import activity, you can also manage data transfers without using complex SQL queries.
products:
  - Marketing
  - Marketing Cloud Engagement
release: "264"
---
# Import or Copy Large Datasets

When transferring a large dataset from an external file or a data extension, use the Data Copy or Import activity to help prevent data loss, minimize downtime, and maintain business continuity. With the Data Copy or Import activity, you can also manage data transfers without using complex SQL queries.

- **[Import or Copy a Large Dataset Using a Data Extension as the Source](https://help.salesforce.com/s/articleView?id=mktg.mc_as_copy_large_datasets_using_data_extension.htm&release=264.0.0&type=5)**  
    Use the Data Copy or Import activity to copy data between data extensions and eliminate the need for complex SQL queries. You can use a data extension as the source to update another data extension but not a subscriber list. To update a subscriber list, use an external file.
- **[Import or Copy a Large Dataset Using an External File as the Source](https://help.salesforce.com/s/articleView?id=mktg.mc_as_update_a_list_or_data_extension_using_an_external_file.htm&release=264.0.0&type=5)**  
    Use an external file with the Automation Studio Data Copy or Import (formerly Import File) activity to update a list or data extension.