Can I use notes in the Platform Developer I exam?

No. The official guide states that no hard-copy or online materials may be referenced during the proctored exam, whether you sit it at a testing center or online. Use this sheet for final revision before exam day only.

Salesforce PD1 Cheat Sheet: Apex, LWC & Governor Limits

A final-revision summary for the Salesforce Platform Developer I (PD1) exam. Study aid only - no reference materials are allowed in the proctored exam.

The four sections (official weights, Summer ‘25 outline)

#	Section	Weight
1	Developer Fundamentals	27%
2	Process Automation and Logic	28%
3	User Interface	25%
4	Testing, Debugging, and Deployment	20%

Data modelling essentials

Term	Idea
Lookup relationship	Loose link; child can exist without parent
Master-detail	Tight link; cascade delete, detail inherits sharing, enables roll-ups
Roll-up summary	Aggregates child values on the master; master-detail only
Junction object	Two master-details = a many-to-many relationship
External ID	Marked field used to match records in upserts and integrations
Formula field	Calculated when read, not stored, not editable

Apex and triggers

Term	Idea
Trigger.new / Trigger.old	New values vs prior values in trigger context
Before trigger	Modify the records being saved; no extra DML needed
After trigger	Records saved with IDs; use for related-record work
Bulkification	Write for up to 200 records per batch; no SOQL/DML inside loops
Save order of execution	Before triggers run, then validation rules, then after triggers, then assignment/auto-response and the rest
Recursion guard	Static variable pattern stops a trigger re-firing on its own update
with sharing	Enforces the running user’s record-sharing rules in a class

SOQL vs SOSL vs DML

Term	Idea
SOQL	Structured query of one object (plus its related records)
SOSL	Text search across multiple objects at once
DML	insert, update, upsert, delete, undelete, merge
Upsert	Insert-or-update in one call, matched on ID or an external ID

Governor limits worth memorising (per synchronous transaction)

Commonly tested values; always confirm current figures in the official Apex Developer Guide, as limits can change.

Limit	Common value
SOQL queries	100
DML statements	150
Rows retrieved by SOQL	50,000
Rows processed by DML	10,000

User interface

Term	Idea
Lightning Web Components	Modern default; built on web standards
@AuraEnabled	Exposes a static Apex method to components
@wire	Reactive data provisioning in LWC
Custom event	Child-to-parent communication in LWC
Lightning Message Service	Messaging across the page, beyond one hierarchy
Lightning Data Service	Record access with caching, no Apex needed
UI security	Enforce CRUD/FLS in Apex (WITH SECURITY_ENFORCED, Security.stripInaccessible)
Agentforce	AI agents whose actions can invoke developer-built logic such as Apex

Testing and deployment

Term	Idea
@isTest	Marks test code; org data not visible by default
Test.startTest/stopTest	Fresh governor limits; async jobs complete at stopTest
Coverage rule	75% overall required for production deployment; assertions prove behaviour
System.runAs	Simulates a user’s record-sharing context in tests
Sandbox / scratch org	Copy of production vs short-lived source-driven org
Deployment paths	Change sets (point-and-click) or Salesforce DX / CLI (source-driven)

Exam facts at a glance

Item	Value
Questions	60 scored multiple-choice + up to 5 unscored
Duration	105 minutes
Passing score	68% (about 41 of 60 scored)
Fee	US$200 registration, US$100 retake, plus applicable taxes (USD/JPY pricing)
Delivery	Proctored, onsite or online; booked through your Trailhead account
Version	Questions align to the Summer ‘25 Release, including Agentforce topics
Validity	No fixed expiry; free annual maintenance badge on Trailhead is mandatory
Prerequisite	None; PD1 is itself the prerequisite for Platform Developer II

A naming note

The official exam guide now titles the credential “Salesforce Certified Platform Developer” without the “I”. It is the same certification - the industry still says Platform Developer I or PD1, and it remains the prerequisite for Platform Developer II. Confirm all details on the official Salesforce exam guide before booking.

Salesforce Platform Developer I Cheat Sheet