Salesforce customers who manage large data volume in their orgs must architect record ownership carefully to ensure peak performance. When you have a large number of records owned by a single user in Salesforce, we call that an “ownership skew”.
One of the common patterns involves customers concentrating ownership of data so that a single user or queue, or all the members of a single role or public group, owns most or all of the records for a particular object.
If the user(s) must have a role in sharing data, we recommend that you:
1. Place them in a separate role at the top of the hierarchy
2. Not move them out of that top-level role
3. Keep them out of public groups that could be used as the source for sharing rules
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