Salesforce Certified Platform Developer II — Question 148

Given a list of Opportunity records named opportunityList, which code snippet is best for querying all Contacts of the Opportunity's Account?

Answer options

• A. List <Contact> contactList = new List <Contact>(); for(Opportunity o : opportunityList){ Account a = [SELECT Id, (SELECT Id FROM Contacts) FROM Account WHERE Id = :o.AccountId] contactList.addAll(a.Contacts); )
• B. List <Contact> contactList = new List <Contact>(); Set <Id> accountIds = new Set <Id> (); for (Opportunity o : opportunityList){ contactIds.add(o.ContactId); } for(Contact c : [SELECT Id FROM Contact WHERE Id IN :contactIds]){ contactList.add(c); }
• C. List <Contact> contactList = new List <Contact>(); Set <Id> accountIds = new Set <Id> (); for(Opportunity o : opportunityList){ accountIds.add(o.AccountId); } for(Account a : [SELECT Id, (SELECT Id FROM Contacts) FROM Account WHERE Id IN :accountIds]){ contactList.addAll(a.Contacts); }
• D. List <Contact> contactList = new List <Contact>(); for ( Contact c : [SELECT Id FROM Contact WHERE AccountId IN :opportunityList.AccountId] ){ contactList.add(c); }

Correct answer: C

Explanation

Option C is correct because it efficiently collects all Account Ids from the Opportunity records, then queries the Accounts in a single SOQL statement to retrieve their related Contacts. Option A incorrectly queries each Opportunity's Account individually, leading to inefficient SOQL usage. Option B focuses on Contact Ids instead of Account Contacts, missing the requirement. Option D incorrectly tries to reference AccountIds directly from the list instead of aggregating them first.