What is a Lookup Filter in Salesforce?
A lookup filter limits which records can be associated within an object relationship.
Why use Lookup Filters?
Use lookup filters to enforce data quality and increase usability within object relationships.
What are the two types for Lookup Filters in Salesforce?
Required
Optional
What are Required Lookup Filters?
Required filters (as shown above) require that data within the target record meet the specified criteria. If criteria is not met, the record cannot be saved.
What are Optional Lookup Filters?
Optional filters will display a warning during search, but will not outright block the record from being saved.