SOQL Error System.QueryException: Non-selective query against large object type

 

Sometimes you may see this error while configuring the Selection or the Active Record Criteria in an Assignment Group. It can happen due to the use of non-selective indexed fields. It can be resolved by the use of selective indexed fields  that return a lower/reasonable number of rows.

 

Here's a Salesforce article explaining this error: SOQL Error System.QueryException: Non-selective query against large object type (salesforce.com)

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