Salesforce Platform Developer I: Expert Tips and Practice Strategies

Introduction

The Salesforce Platform Developer I certification (PD1) is your gateway to becoming a professional Salesforce developer. This credential validates your ability to build custom applications on the Lightning Platform using Apex and Lightning Web Components.

This guide provides expert tips, code examples, and proven strategies to help you succeed on your first attempt.

Understanding the Platform Developer I Exam

Exam Specifications

• Exam Code: Platform Developer I (PD1)
• Questions: 60 multiple-choice/multiple-select
• Duration: 105 minutes
• Passing Score: 68%
• Cost: $200 USD ($100 USD for retake)
• Prerequisites: None (but Admin knowledge recommended)

What Makes This Exam Challenging?

Unlike the Administrator exam, PD1 requires:

1. Hands-on coding experience with Apex and Lightning
2. Understanding of programming concepts (OOP, design patterns)
3. Knowledge of Salesforce architecture and limits
4. Problem-solving skills for complex scenarios

Exam Topics Breakdown

1. Developer Fundamentals (23%)

Core Concepts:

• Multi-tenant architecture
• MVC pattern in Salesforce
• Governor limits and best practices
• Development lifecycle

Key Points to Master:

// Understanding Governor Limits
// BAD: Query inside loop
for(Account acc : accounts) {
    List<Contact> cons = [SELECT Id FROM Contact WHERE AccountId = :acc.Id];
}

// GOOD: Bulkified query
Set<Id> accountIds = new Set<Id>();
for(Account acc : accounts) {
    accountIds.add(acc.Id);
}
List<Contact> cons = [SELECT Id, AccountId FROM Contact WHERE AccountId IN :accountIds];

Pro Tip: Always write bulkified code. Every question about Apex code should make you think about governor limits.

2. Data Modeling and Management (25%)

Topics:

• Object relationships (Lookup vs Master-Detail)
• Schema Builder
• Field types and custom settings
• Data validation

Important Relationships Comparison:

| Feature | Lookup | Master-Detail | |---------|--------|---------------| | Required | Optional | Required | | Cascade Delete | No | Yes | | Sharing Rules | Independent | Inherits from master | | Roll-up Summary | No | Yes |

Code Example:

// Accessing parent record in relationship
Account acc = new Account(Name = 'Test Account');
insert acc;

Contact con = new Contact(
    FirstName = 'John',
    LastName = 'Doe',
    AccountId = acc.Id  // Lookup relationship
);
insert con;

// Query with relationship
Contact queriedContact = [
    SELECT Id, Account.Name, Account.Industry
    FROM Contact
    WHERE Id = :con.Id
];
System.debug(queriedContact.Account.Name);

3. Business Logic and Process Automation (30%)

Coverage:

• Apex triggers
• Apex classes
• Exception handling
• Asynchronous Apex (Future, Batch, Queueable, Scheduled)

Trigger Best Practices:

// BAD: Logic in trigger
trigger AccountTrigger on Account (before insert) {
    for(Account acc : Trigger.new) {
        acc.Name = acc.Name.toUpperCase();
        // More logic...
    }
}

// GOOD: Handler pattern
trigger AccountTrigger on Account (before insert, after insert) {
    AccountTriggerHandler.handleTrigger();
}

// Handler class
public class AccountTriggerHandler {
    public static void handleTrigger() {
        if(Trigger.isBefore && Trigger.isInsert) {
            beforeInsert(Trigger.new);
        }
    }

    private static void beforeInsert(List<Account> newAccounts) {
        for(Account acc : newAccounts) {
            acc.Name = acc.Name.toUpperCase();
        }
    }
}

Asynchronous Apex Comparison:

// Future Method - Simple async operation
@future
public static void updateRecordsAsync(Set<Id> recordIds) {
    // Limit: No complex objects as parameters
}

// Queueable - More flexible
public class UpdateRecordsQueueable implements Queueable {
    private List<Account> accounts;

    public UpdateRecordsQueueable(List<Account> accounts) {
        this.accounts = accounts;
    }

    public void execute(QueueableContext context) {
        // Can chain more queueable jobs
        update accounts;
    }
}

// Batch Apex - Large data volumes
public class UpdateAccountsBatch implements Database.Batchable<SObject> {
    public Database.QueryLocator start(Database.BatchableContext bc) {
        return Database.getQueryLocator('SELECT Id, Name FROM Account');
    }

    public void execute(Database.BatchableContext bc, List<Account> scope) {
        // Process up to 200 records at a time
        update scope;
    }

    public void finish(Database.BatchableContext bc) {
        // Post-processing
    }
}

4. User Interface (23%)

Topics:

• Lightning Web Components basics
• Visualforce fundamentals
• Lightning App Builder
• Static resources

LWC Example:

// helloWorld.js
import { LightningElement, track } from 'lwc';

export default class HelloWorld extends LightningElement {
    @track message = 'Hello, Salesforce!';

    handleChange(event) {
        this.message = event.target.value;
    }
}

<!-- helloWorld.html -->
<template>
    <lightning-card title="Hello World Component">
        <div class="slds-m-around_medium">
            <lightning-input
                label="Enter Message"
                value={message}
                onchange={handleChange}>
            </lightning-input>
            <p class="slds-m-top_medium">{message}</p>
        </div>
    </lightning-card>
</template>

5. Testing and Debugging (16%)

Requirements:

• 75% code coverage minimum
• Test data creation
• System assertions
• Debug logs

Test Class Example:

@isTest
private class AccountTriggerTest {

    @testSetup
    static void setupTestData() {
        // Create test data once for all test methods
        List<Account> accounts = new List<Account>();
        for(Integer i = 0; i < 200; i++) {
            accounts.add(new Account(Name = 'Test ' + i));
        }
        insert accounts;
    }

    @isTest
    static void testAccountCreation() {
        // Test
        Test.startTest();
        Account acc = new Account(Name = 'New Test Account');
        insert acc;
        Test.stopTest();

        // Verify
        Account insertedAccount = [SELECT Id, Name FROM Account WHERE Id = :acc.Id];
        System.assertEquals('NEW TEST ACCOUNT', insertedAccount.Name,
                          'Account name should be uppercase');
    }

    @isTest
    static void testBulkCreation() {
        // Bulk test
        List<Account> newAccounts = new List<Account>();
        for(Integer i = 0; i < 200; i++) {
            newAccounts.add(new Account(Name = 'Bulk Test ' + i));
        }

        Test.startTest();
        insert newAccounts;
        Test.stopTest();

        // Verify bulk operation
        List<Account> insertedAccounts = [SELECT Id FROM Account WHERE Name LIKE 'BULK TEST%'];
        System.assertEquals(200, insertedAccounts.size(), 'Should insert 200 records');
    }
}

Study Strategy for Developers

Phase 1: Foundations (Weeks 1-2)

Focus Areas:

1. Complete Trailhead Trails

   • Apex Basics & Database
   • Apex Triggers
   • Asynchronous Apex
   • Lightning Web Components Basics

2. Build Practice Projects

   • Create a custom object with triggers
   • Build a simple LWC component
   • Write test classes for your code

Daily Practice:

- 2 hours: Trailhead modules
- 1 hour: Coding in Developer org
- 30 minutes: Review documentation

Phase 2: Advanced Topics (Weeks 3-4)

Deep Dive Into:

1. Governor Limits

   • SOQL/SOSL limits
   • DML operation limits
   • Heap size limits
   • CPU time limits

2. Design Patterns

   • Trigger handler pattern
   • Bulkification patterns
   • Singleton pattern

3. Testing Strategies

   • Test data factories
   • Mocking external services
   • Achieving 100% coverage

Phase 3: Practice & Review (Week 5)

Final Preparation:

1. Practice Exams - Take 3-5 full practice tests
2. Code Reviews - Review all your practice code
3. Flashcards - Memorize key concepts and syntax
4. Mock Scenarios - Solve real-world problems

Common Exam Mistakes to Avoid

1. Not Understanding Context Variables

// Know the difference!
Trigger.new          // List<SObject> - New versions
Trigger.old          // List<SObject> - Old versions
Trigger.newMap       // Map<Id, SObject> - New versions with Ids
Trigger.oldMap       // Map<Id, SObject> - Old versions with Ids

Trigger.isBefore     // Boolean
Trigger.isAfter      // Boolean
Trigger.isInsert     // Boolean
Trigger.isUpdate     // Boolean
Trigger.isDelete     // Boolean
Trigger.isUndelete   // Boolean

2. Ignoring Governor Limits

Remember:

• 100 SOQL queries per transaction
• 150 DML statements per transaction
• 50,000 records retrieved by SOQL
• 10,000 records processed by DML
• 6 MB heap size (synchronous)
• 12 MB heap size (asynchronous)

3. Poor Test Class Practices

Don't:

• Use @SeeAllData=true
• Depend on existing org data
• Ignore bulk testing
• Skip negative test cases

Do:

• Create test data in methods or @testSetup
• Test bulk scenarios (200+ records)
• Test negative cases and exceptions
• Verify with System.assert statements

Essential Resources

Official Salesforce

1. Apex Developer Guide - Your coding bible
2. Lightning Web Components Dev Guide
3. Trailhead Superbadges:
   • Apex Specialist
   • Process Automation Specialist
   • Lightning Web Components Specialist

Practice Platforms

1. Certifyforce - AI-powered practice exams with code examples
2. Focus on Force - Practice questions
3. Salesforce Stack Exchange - Community Q&A

Development Tools

1. VS Code with Salesforce Extensions
2. Developer Console
3. Workbench - For testing SOQL/SOSL
4. Postman - REST API testing

Advanced Tips from Certified Developers

Tip 1: Master Collection Manipulation

// Lists
List<Account> accounts = new List<Account>();
accounts.add(new Account(Name='Test'));

// Sets - No duplicates
Set<Id> accountIds = new Set<Id>();

// Maps - Key-value pairs
Map<Id, Account> accountMap = new Map<Id, Account>(
    [SELECT Id, Name FROM Account]
);

Tip 2: Understand SOQL vs SOSL

// SOQL - Query one object (can include related objects)
List<Account> accounts = [
    SELECT Id, Name, (SELECT Id, FirstName FROM Contacts)
    FROM Account
    WHERE Industry = 'Technology'
];

// SOSL - Search multiple objects
List<List<SObject>> searchResults = [
    FIND 'Acme'
    IN ALL FIELDS
    RETURNING Account(Name), Contact(FirstName, LastName)
];

Tip 3: Exception Handling

try {
    insert accounts;
} catch(DmlException e) {
    System.debug('DML Error: ' + e.getMessage());
    // Handle gracefully
} catch(Exception e) {
    System.debug('General Error: ' + e.getMessage());
}

Exam Day Strategy

Time Management

• Average per question: 1.75 minutes
• First pass: Answer questions you're confident about (45 minutes)
• Second pass: Tackle harder questions (40 minutes)
• Review: Check flagged questions (20 minutes)

Question Analysis

1. Read the entire question carefully
2. Identify what's being asked (best practice, error, requirement)
3. Eliminate obviously wrong answers
4. Consider governor limits and best practices
5. Choose the most Salesforce-recommended approach

After Certification: Next Steps

Immediate Actions

1. Add credential to LinkedIn and resume
2. Update Salesforce Trailblazer profile
3. Join developer forums and communities

Career Development

1. Build Portfolio Projects

   • GitHub repositories
   • AppExchange apps
   • Open source contributions

2. Advanced Certifications

   • Platform Developer II
   • JavaScript Developer I
   • B2C Commerce Developer

3. Continuous Learning

   • Attend Salesforce events (Dreamforce, TrailheaDX)
   • Read release notes quarterly
   • Complete new Trailhead content

Conclusion

The Platform Developer I certification requires dedication, hands-on coding practice, and strategic study. Focus on writing clean, bulkified code and understanding Salesforce best practices rather than just memorizing syntax.

Use this guide as your roadmap, practice extensively in your Developer org, and leverage quality practice exams to identify your weak areas. With consistent effort and practical experience, you'll be ready to pass the exam with confidence.

Start your developer journey today with Certifyforce's AI-powered practice exams tailored for Platform Developer I!

Happy coding! 🚀