Which operator can be used to filter for 'not null' values in Relativity?

The correct operator for filtering 'not null' values in Relativity is the percent symbol (%). This operator is commonly used in Relativity to specify that the value should not be blank or null. When used in a query or as a filter criteria, the percent symbol matches any characters, effectively allowing users to find records that have a value present.

In the context of data queries, when you want to return records that contain any data, using the percent symbol serves this purpose well since it represents any non-empty string. Therefore, records with null or blank values would not meet the criteria when employing this operator, thus filtering them out.

Other options don't serve the purpose of filtering for 'not null' values effectively. The IS SET operator is typically utilized for checking if a field is populated but does not specifically target non-null values in the same way as the percent symbol does. The BETWEEN operator is designed for range queries between two specific values, and the equal to operator checks for exact matches rather than the presence of any value.