Developer Fundamentals27% of the exam
Multi-tenancy, MVC and the Lightning Component Framework
How one shared, metadata-driven platform serves every org and why that forces governor limits, how Salesforce features map onto Model-View-Controller, and how Lightning web components and Aura components fit the Lightning Component Framework.
Understand multi-tenant concepts and design frameworks, such as MVC architecture and Lightning Component Framework.
~8 min read · 20 practice questions ·
What the exam expects
- Explain how many orgs share one database and runtime yet stay isolated, and why that makes governor limits unavoidable.
- Describe what happens when you create an object, field or Apex class in a metadata-driven platform, and why upgrades do not break customizations.
- Map objects, pages, components, Apex and automation onto the Model, View and Controller layers.
- Compare Lightning web components and Aura components within the Lightning Component Framework, including bundle structure and interoperability.
- Key terms: tenant/org (one customer's isolated slice of the shared platform, identified by OrgID); metadata (data that describes objects, fields, UI and logic); governor (a runtime-enforced resource limit); MVC (splitting an app into data, presentation and logic); Lightning components (the umbrella term for Aura components and Lightning web components).
Key facts
Tenant isolation
- Detail
- Every org-specific row in the shared tables carries an OrgID
Creating an object or field
- Detail
- Stores metadata in MT_Objects/MT_Fields; no physical table, no DDL, no downtime
Expensive query
- Detail
- A query the optimizer regards as too expensive throws a runtime exception
Data access from Apex
- Detail
- Inline SOQL and SOSL to read, DML to write; no direct SQL
Before every upgrade
- Detail
- Salesforce runs all unit tests to confirm custom Apex still works
Exceeding a governor
- Detail
- Throws a runtime exception that can't be handled
Transaction wall-clock ceiling
- Detail
- 10 minutes, sync and async
Async executions per 24 hours
- Detail
- 250,000 or user licenses × 200, whichever is greater; org-wide
Scheduled Apex classes
- Detail
- 100 at once (5 in Developer Edition)
LWC and Aura nesting
- Detail
- Aura can contain LWC; LWC can't contain Aura
LWC bundle naming
- Detail
- Folder and files share one name;
myComponentis<c-my-component>in markup
LWC JavaScript class
- Detail
- Default export extends
LightningElementfromlwc
Sources for this section (6)
- Multitenant Architecturedeveloper.salesforce.com (opens in a new tab)
- What is Apex?developer.salesforce.com (opens in a new tab)
- Governor Limitsdeveloper.salesforce.com (opens in a new tab)
- LWC and Aura Togetherdeveloper.salesforce.com (opens in a new tab)
- LWC Component Folderdeveloper.salesforce.com (opens in a new tab)
- LWC JavaScript Filedeveloper.salesforce.com (opens in a new tab)
- Why can Salesforce add a custom field without locking other tenants?
- Why does Apex enforce governor limits at all?
- When does adding more Queueable jobs stop helping a high-volume org?
- When is Aura still the right choice for a new component?
- Which class must a Lightning web component's JavaScript file extend?
The questions are free to read. Answers with their sources and self-grading are included with the pack.
Keep reading with the Platform Developer pack
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- All 21 lessons of the Platform Developer guide, with reading progress
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