You can store data outside Salesforce and still access in your org or Data
Cloud.
External Objects
External objects are similar to custom objects, but external object record
data is stored outside your org. You can access data in external objects by using
OData and other adaptors.
Zero Copy Objects
In some cases, Salesforce is deeply integrated into data stored in other
products, such as Snowflake or AWS. In this case, the data is stored outside
Salesforce, but it's accessible through Data Cloud.
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