As part of a new integration, a developer is asked to implement a new custom search functionality that is capable of performing unrestricted queries and can account for all values within a custom picklist field, type__z, on the Opportunity object. The search feature must also account for NULL values.
The organization-wide default for the Opportunity object is set to Public Read-Only, and a new custom index has been created for the Type__c field. There are more than 5 million Opportunity records within the environment and a considerable amount of the existing records have NULL values for the picklist
Which technique should the developer implement to maximize performance when querying NULL values?
A. Create a formula field that substitutes NULL values for a string of text, create an index for the formula field, then use the formula within the WHERE clause.
B. Perform two SOQL queries; one to query Opportunities where Type__c - NULL, and another to query where Type_: - HBLL, then join the result set using Apex.
C. Use a SOSL query to return ALL opportunities that have a value of NULL in any field.
D. Use the OS operator to combine WHERE clauses to strictly search for each value within the picklist, including Type__c ` NULL.