Salesforce Development: Complete Interview and Implementation Guide

A comprehensive guide covering Apex triggers, Lightning Web Components, security models, and integration patterns for Salesforce developers and administrators.

Triggers and Apex Fundamentals

Order of Execution in a Trigger Context

When a record is inserted, Salesforce follows a specific sequence:

1. System Validation Rules (required fields, field formats)

2. Before Triggers (executes before record is saved)

3. Custom Validation Rules (user-defined rules)

4. After Triggers (executes after record is saved)

5. Assignment Rules (for Cases and Leads)

6. Auto-response Rules (email notifications)

7. Workflow Rules (field updates, email alerts)

8. Process Builder / Flows (automation)

9. Escalation Rules (for Cases)

10. Post-commit Logic (email sending, async sharing calculations)

When to Use Before vs. After Triggers

• Before Triggers: Use when you need to update or validate the same record that initiates the trigger.

• After Triggers: Use when you need to access the record's ID or perform DML operations on related records.

Troubleshooting a Bulk Trigger Failure

Common issues include:

• SOQL or DML operations inside loops

• Lack of bulkification

• Missing error handling

• Recursive trigger execution

Trigger to Create a Contact When an Account is Created

An after insert trigger on the Account object can create a new Contact record and associate it with the new Account:

trigger CreateContactOnAccount on Account (after insert) {
    List<Contact> contactsToCreate = new List<Contact>();
    
    for (Account acc : Trigger.new) {
        contactsToCreate.add(new Contact(
            LastName = acc.Name + ' Contact',
            AccountId = acc.Id
        ));
    }
    
    if (!contactsToCreate.isEmpty()) {
        insert contactsToCreate;
    }
}