Let a “system user” own all the Account records and make this user part of the highest-level role in the Role Hierarchy. https://developer.salesforce.com/blogs/engineering/2012/06/architect-salesforce-record-ownership-skew-for-peak-performance-in-large-data-volume-environments.html
Let a “system user” own all the Account records without assigning any role to this user in Role Hierarchy.
Let a “system user†own the Account records and assign this user to the lowest-level role in the Role Hierarchy. Let a “system user†own all the Account records without assigning any role to this user in Role Hierarchy.