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Platform Developer II

Checklist progress

0/197Learned

Platform Developer II

Study Checklist

  • Platform Administrator
  • Platform App Builder
  • Platform Foundations
  • Platform Developer
  • Platform Administrator II
  • Agentforce Sales Consultant
  • Agentforce Service Consultant
  • Platform Data Architect
  • Platform Development Lifecycle and Deployment Architect
  • Platform Identity and Access Management Architect
  • Platform Integration Architect
  • Platform Sharing and Visibility Architect
  • Heroku Architect
  • B2C Solution Architect
  • Experience Cloud Consultant
  • Agentforce Field Service and Operations Consultant
  • Agentforce Nonprofit Consultant
  • Data 360 Consultant
  • Omnistudio Consultant
  • CRM Analytics and Einstein Discovery Consultant
  • Platform User Experience Designer
  • Platform Strategy Designer
  • B2C Commerce Developer
  • JavaScript Developer
  • Omnistudio Developer
  • Platform Developer II
  • Marketing Cloud Engagement Administrator
  • Marketing Cloud Engagement Specialist
  • Marketing Cloud Engagement Consultant
  • Agentforce Sales Foundations
  • Business Analyst
  • Marketing Cloud Engagement Developer
  • Marketing Cloud Engagement Foundations
  • Agentforce Specialist
  • Agentforce Life Sciences Consultant
  • B2B Commerce Administrator AP
  • B2B Commerce Developer AP
  • Agentforce Consumer Goods AP
  • Agentforce Financial Services AP
  • Agentforce Health AP
  • Agentforce Manufacturing AP
  • MuleSoft Integration Foundations
  • MuleSoft Developer
  • MuleSoft Developer II
  • MuleSoft Platform Integration Architect
  • MuleSoft Platform Architect
  • Tableau Desktop Foundations
  • Tableau Data Analyst
  • Tableau Consultant
  • Tableau Server Administrator
  • Tableau Architect

Checklist progress

0/197Learned

  • How enabling multi-currency in an org adds the CurrencyIsoCode field to currency-enabled sObjects and what happens to SOQL queries that filter or aggregate currency fields
  • The difference between single currency and advanced (dated exchange rate) multi-currency and how dated exchange rates affect opportunity and forecast roll-ups in Apex
  • How SOQL handles currency conversion with the convertCurrency() function and its syntax in aggregate queries
  • The impact of multi-currency on SOQL aggregate functions (SUM, AVG) — whether results are in the corporate currency or the record currency
  • How Apex code must handle the IsoCode field when inserting or updating records in a multi-currency org, including required field population
  • How to use the CurrencyType and DatedConversionRate sObjects in Apex to retrieve exchange rates programmatically
  • How the System.Label class and custom labels support localization in Apex and Visualforce, and how translations are applied at runtime
  • Which Apex methods and System classes are affected by the running user's locale
  • Date and number formatting differences between User.LocaleSidKey values in Apex
  • The significance of with sharing, without sharing, and inherited sharing keywords in Apex and how they interact with the running user's record visibility
  • How Apex class sharing is inherited when one class calls another class declared with a different sharing keyword
  • The difference in behavior between Database.query() called from a with sharing class versus a without sharing class when record-level security is the concern
  • When Apex managed sharing is the correct solution versus a sharing rule or manual share, given a scenario with dynamic or complex record-access requirements
  • The structure of a sharing object (e.g., AccountShare) and the meaning of its RowCause, UserOrGroupId, and AccessLevel fields
  • How to grant record access programmatically by inserting rows into a sharing object from Apex, including required field values
  • How a custom RowCause (share reason) is created and why it is required for Apex managed sharing to survive record ownership changes
  • The difference between Custom Metadata Types and Custom Settings (hierarchy vs. list) in deployment and packaging
  • When to use Custom Metadata Type records instead of Custom Settings for configuration that must be deployable as metadata between orgs
  • How to access hierarchy custom settings in Apex using getInstance() versus getOrgDefaults() and which takes precedence
  • How to query Custom Metadata Type records in Apex using SOQL (FROM MyType__mdt) and what special rules apply (e.g., no DML allowed)
  • Data availability of Custom Metadata versus Custom Settings in Apex test contexts
  • How Custom Metadata records are included in Apex test execution without needing test data setup, unlike Custom Setting records
  • How to use the Metadata.Operations class to deploy or retrieve Custom Metadata Type records programmatically in Apex
  • The Protected attribute on Custom Metadata Type records and its implications for managed package subscribers

Given a scenario, identify the considerations of interactions between multiple processes, both declarative and programmatic.

0/4

  • How Record-Triggered Flows and Apex triggers interact in the same transaction and the execution order between before-save flows, triggers, and after-save flows
  • How governor limits are shared across a single transaction that includes both declarative (Flow) and programmatic (Apex) automation
  • How multiple Record-Triggered Flows on the same object and trigger fire in a single transaction and potential for limit exhaustion
  • The risk of recursion when a trigger invokes a flow that causes the same trigger to fire again, and the mechanism to prevent it

Given a scenario, propose and justify the optimal programmatic or declarative solution.

0/5

  • When to use a before-save Record-Triggered Flow versus a before-trigger in Apex for field updates on the same record, based on performance and complexity
  • When to escalate from a declarative flow to Apex code, such as when HTTP callouts, complex data transformations, or dynamic SOQL are required
  • The benefits of using an invocable Apex method called from a Flow versus writing a full trigger for a specific automation task
  • How to declare an @InvocableMethod with @InvocableVariable-annotated input/output inner classes so the method can be called from Flow with structured data
  • How Outbound Messages (a declarative SOAP-based workflow action) differ from Apex callouts and when each is the appropriate integration approach

Demonstrate knowledge of the best practices for writing Apex triggers.

0/6

  • Which trigger context variables are available in before insert, before update, after insert, and after update contexts (Trigger.new, Trigger.old, Trigger.newMap, Trigger.oldMap)
  • How Trigger.isExecuting, Trigger.isBefore, Trigger.isAfter, Trigger.isInsert, Trigger.isUpdate context Boolean variables are used to route logic
  • Why DML and SOQL statements must not be placed inside trigger for-loops and the governor limit consequences if they are
  • How to bulkify a trigger by collecting IDs into a Set, querying outside the loop, and building maps for efficient record lookup
  • The one-trigger-per-object pattern and how to implement a trigger handler class to centralize logic and support unit testing
  • How to use a static Boolean flag in a handler class to prevent recursive trigger execution

Describe the Apex features available for error handling and maintaining transactional integrity.

0/7

  • How try-catch-finally blocks work in Apex and which exception types can be caught (DmlException, QueryException, etc.)
  • How to create a custom exception class in Apex by extending Exception, and when a custom exception should be thrown versus re-throwing a caught exception
  • The difference between Database.insert(records, false) with partial success and a standard DML insert that rolls back the entire transaction on any failure
  • How Database.SaveResult, Database.UpsertResult, and Database.DeleteResult are used to inspect per-record errors when allOrNone is false
  • The behavior of addError() on a trigger record and how it prevents DML from completing while surfacing a user-visible error message
  • How uncaught exceptions in an after-trigger cause the entire transaction (including all before-trigger DML) to be rolled back
  • How Savepoint and Database.rollback() are used to roll back DML to a specific point in a transaction without aborting the entire transaction

Demonstrate how and where to use advanced keywords in a SOQL query structure.

0/11

  • How to write child-to-parent relationship queries in SOQL using dot notation and the difference between standard and custom relationship names (__r suffix)
  • How to write a parent-to-child relationship query (nested SELECT) in SOQL and access the child records in Apex
  • The syntax of SOQL aggregate functions (COUNT, SUM, AVG, MIN, MAX) with GROUP BY
  • How the HAVING clause filters grouped results in SOQL aggregate queries
  • How OFFSET and LIMIT work together for pagination in SOQL, and the maximum allowed OFFSET value
  • How to write a SOQL semi-join (IN subquery) and its valid syntax constraints
  • How to write a SOQL anti-join (NOT IN subquery) and its valid syntax constraints
  • How to use the WITH SECURITY_ENFORCED clause in SOQL to enforce field- and object-level security, and what exception is thrown if a field is inaccessible
  • How to use FIELDS(ALL), FIELDS(STANDARD), and FIELDS(CUSTOM) in SOQL queries and their governor limit implications
  • The syntax and purpose of TYPEOF in polymorphic SOQL queries against fields like What or Who on Activity
  • The syntax and use of FOR UPDATE in SOQL to lock records and prevent concurrent modifications during a transaction

Analyze a set of requirements and determine the benefits of using asynchronous Apex coding.

0/13

  • Future and Queueable Apex — primary use cases and governor limits
  • Batch Apex — primary use cases and governor limits
  • Scheduled Apex — primary use cases and governor limits
  • How @future(callout=true) enables HTTP callouts from a trigger context and the constraints on @future method signatures (only primitives and collections of primitives)
  • How Queueable Apex differs from @future methods in terms of support for non-primitive parameters, job monitoring, and the ability to chain jobs
  • How Queueable Apex supports chaining jobs via System.enqueueJob() inside execute() and the maximum chaining depth in non-sandbox contexts
  • When to choose Batch Apex over Queueable for processing large data volumes, specifically when the record count exceeds what a single transaction can handle
  • The Database.Batchable interface methods (start, execute, finish) and the governor limits that apply to each method in batch Apex
  • How Database.Stateful is used in batch Apex to persist instance variable values across execute() method calls
  • How to pass state between Queueable job chains and between batch start/execute/finish methods using instance variables
  • The maximum number of batch Apex jobs that can be queued or active simultaneously and the impact on System.enqueueJob() calls within a batch context
  • How to implement the Schedulable interface and use a CRON expression string with System.schedule() to run Apex at a recurring calendar-based schedule
  • How to schedule a batch Apex job to run at a specific time using System.scheduleBatch() versus implementing the Schedulable interface

Given a scenario and requirements, identify the appropriate dynamic Apex feature to use in the solution.

0/8

  • How to construct and execute a dynamic SOQL query using Database.query(queryString) and the risks of SOQL injection if user input is not sanitized
  • How String.escapeSingleQuotes() prevents SOQL injection in dynamic queries and when it must be applied
  • How to use Schema.getGlobalDescribe() and Schema.describeSObjects() to dynamically retrieve sObject and field metadata at runtime
  • How to use Schema.SObjectType and Schema.SObjectField tokens in Apex for compile-time-safe metadata references compared to string-based describe calls
  • How to retrieve field-level describe information (isAccessible, isCreateable, isUpdateable) and enforce CRUD/FLS programmatically before DML
  • How to use dynamic DML with Database.query, Database.insert, and sObject.put() / sObject.get() for field access by API name string
  • How to dynamically build a list of field API names from describe results and construct a SOQL SELECT clause programmatically for a generic query utility
  • How to use Type.forName() and dynamic instantiation of Apex classes to implement a strategy or plugin pattern

Given a scenario, identify the appropriate publish / subscribe logic for platform events.

0/10

How to publish a Platform Event from Apex using EventBus.publish() and the difference between synchronous and transaction-scoped publishing

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How Publish After Commit (default) versus Publish Immediately affects when subscribers receive a platform event relative to the publisher's transaction

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How to subscribe to Platform Events in Apex using an after-insert trigger on the event object and the governor limits that apply

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How LWC and Aura components subscribe to Platform Events using the lightning/empApi or empApi Aura module

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Platform Event delivery durability and replay ID: how subscribers can replay missed events using a stored ReplayId

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The behavior of Platform Events when a publishing transaction is rolled back — whether the event is still delivered to subscribers

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How to use the EventBus.publish() return value and the OperationResult to check whether a Platform Event was successfully published in Apex

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How Change Data Capture (CDC) differs from Platform Events in terms of what triggers the event, what data is included (changed fields only), and which objects support it

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When to use Platform Events versus Change Data Capture for real-time integration scenarios

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When to use Streaming API PushTopics versus Platform Events or Change Data Capture

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Given a scenario, apply programmatic integration techniques and platform features for inbound and outbound communication.

0/11

  • How to make an outbound REST callout from Apex using HttpRequest, HttpResponse, and Http.send(), including setting endpoint, method, headers, and body
  • How Named Credentials abstract endpoint URL and authentication from Apex callout code and the syntax for referencing them (callout:MyNamedCredential/path)
  • The purpose of Remote Site Settings and how they are required for outbound callouts to external endpoints not covered by Named Credentials
  • The callout governor limits (number of callouts per transaction, maximum callout timeout) and the error thrown when they are exceeded
  • How to use JSON.serialize() and JSON.deserialize() in Apex for converting between sObjects/POJOs and JSON strings
  • The difference between JSON.deserialize() and JSON.deserializeStrict() and when to use each
  • How to expose an Apex class as a REST web service using @RestResource, @HttpGet, @HttpPost annotations and how request/response data is accessed
  • How to use the @RestResource urlMapping parameter with path parameters and how to read them from RestContext.request in the Apex method body
  • How to expose Apex methods as SOAP web services using the webService keyword and what types are supported in the WSDL
  • How to implement a StaticResourceCalloutMock in Apex tests to load mock HTTP responses from a static resource file instead of hand-crafting the response body
  • How to handle continuation-based callouts in Visualforce to perform asynchronous server-side callouts without blocking the browser
  • How @AuraEnabled(cacheable=true) and @AuraEnabled differ in terms of server-side caching behavior and which is required for wire adapter compatibility
  • How to return a List, Map, or custom Apex type from an @AuraEnabled method and the serialization rules that apply
  • How the @wire decorator in LWC calls an @AuraEnabled(cacheable=true) Apex method and when the data is refreshed
  • How to imperatively call an Apex method from LWC JavaScript using a promise-based import, versus using @wire
  • How to surface Apex exceptions to LWC callers using AuraHandledException and the effect on the error object received in the component's catch block
  • How apex:actionFunction enables JavaScript to invoke a controller method and optionally perform a partial page refresh via reRender
  • How the apex:actionSupport tag attaches a controller action to a DOM event (e.g., onclick, onchange) on a Visualforce component
  • How apex:actionRegion limits the components that are processed on the server during a partial page submission
  • How apex:actionStatus is used to display a loading indicator during an asynchronous action and how it ties to the status attribute of other action components
  • How apex:actionPoller automatically invokes a controller action at a specified interval and the minimum supported interval
  • How a Visualforce standard set controller enables list-based views with pagination via first(), next(), previous(), last(), and the pageSize property
  • How JavaScript Remoting (@RemoteAction) works in Visualforce, including the method signature requirements and callback structure in JavaScript
  • How Visualforce Remote Objects allow JavaScript-initiated CRUD operations without writing a controller method, and their governor limit behavior
  • How to catch and display errors from imperative Apex calls in LWC using the error property of the catch block and rendering it conditionally
  • How to display page-level errors in LWC using lightning-messages or a custom error message component, versus adding errors to apex:pageMessages in Visualforce
  • How to display field-level errors in LWC using the reportValidity() and setCustomValidity() methods on lightning-input components
  • How apex:pageMessages and apex:messages display controller-added messages and how ApexPages.addMessage() is used in a Visualforce controller
  • When to use LWC versus Aura versus Visualforce given requirements around modern browser standards, performance, and interoperability
  • Scenarios where Visualforce is still the required choice — PDF rendering, printing, embedded in email templates, or legacy apex:detail-heavy pages
  • Which features are exclusive to Aura components (e.g., extends for inheritance, application events) that have no direct LWC equivalent
  • How to use the SLDS grid system (slds-grid, slds-col, slds-size) in LWC and Aura to build responsive layouts
  • How to use the @salesforce/client/formFactor module in LWC to branch display logic based on device form factor (Large, Medium, Small)
  • Conditional rendering with if:true/if:false (Aura) and {#if} (LWC) for showing/hiding UI
  • How lightning/platformShowToastEvent displays toast notifications in LWC and Aura
  • How to dispatch a CustomEvent from a child LWC and handle it in the parent component using the template's event listener syntax
  • The difference between bubbling and non-bubbling CustomEvents in LWC, and how the composed flag affects propagation through shadow DOM boundaries
  • How to call a child LWC component's public method using @api and a reference obtained via this.template.querySelector()
  • How to use slots (default and named) in LWC for component composition and how slot content is rendered in the child template
  • How Aura component events work and when to use them
  • How Aura application events work and when to use them
  • How to use a Lightning Message Channel to communicate between unrelated LWC components, including MessageContext wire adapter and publish/subscribe APIs
  • How the lightning/uiRecordApi wire adapters (getRecord, getFieldValue, getFieldDisplayValue) are used to retrieve and display record data reactively in LWC
  • How to use NavigationMixin in LWC to navigate to a record, a named page, a standard object list, or a URL, and the syntax for each page reference type
  • How LWC shadow DOM prevents direct CSS and JavaScript access across component boundaries and the use of CSS custom properties (:host) to pierce the boundary for styling
  • The benefits of static resources for versioning and caching third-party JavaScript libraries in Salesforce deployments
  • How to reference a static resource in Visualforce using $Resource.ResourceName and the apex:includeScript / apex:stylesheet tags
  • How to reference a static resource in LWC using the @salesforce/resourceUrl import and loadStyle / loadScript from platformResourceLoader
  • The 75% code coverage requirement for Apex deployment to production and how coverage is calculated (lines executed / total executable lines)
  • How Test.startTest() and Test.stopTest() reset governor limits and force asynchronous Apex (future, batch, queueable) to execute synchronously in tests
  • How to use @testSetup to create shared test data once for all test methods in a class, and how DML is rolled back between test methods
  • How to use the Apex Test Data Factory pattern to create reusable, parameterized helper methods for generating test records
  • How to use Test.loadData() with a static resource CSV file to load test records in bulk without writing explicit Apex test data creation code
  • How seeAllData=true on a test class or method works and why it is discouraged in favor of isolated test data
  • How to use the @TestVisible annotation to expose private methods and variables for testing without changing their access modifiers
  • How to use Test.setMock() with an HttpCalloutMock implementation to simulate HTTP callout responses in Apex tests
  • How to use a StaticResourceCalloutMock to return mock HTTP responses stored in a static resource, and when it is preferable to a hand-coded HttpCalloutMock
  • How to use MultiStaticResourceCalloutMock to return different mock responses for multiple endpoints in a single test method
  • How to use Test.setMock() with WebServiceMock to simulate SOAP web service responses in Apex tests
  • How to implement a stub provider using the StubProvider interface and System.StubProvider to mock Apex class behavior without a managed package
  • How to use Jest and @salesforce/sfdx-lwc-jest to unit-test LWC JavaScript without a Salesforce org, including mocking wire adapters and Apex imports
  • How to mock LWC wire adapter responses in Jest tests using the @salesforce/wire-service-jest-util to simulate both data and error states
  • How to use the browser Developer Tools and the Lightning Web Components debug mode to inspect component properties and events at runtime
  • How to use the Lightning Component Inspector browser extension to view the component tree, properties, and event log for LWC and Aura components
  • How to write a Visualforce controller extension that adds behavior to a standard controller and how to test the extension in an Apex test class
  • How to read an Apex debug log to identify which lines of code executed, what DML operations occurred, and where an exception was thrown
  • How to set debug log levels (FINEST, DEBUG, INFO, WARN, ERROR) and which log categories (Apex Code, Database, System) control what appears in the log
  • How to use System.debug() with LoggingLevel parameter and how to read LIMIT_USAGE_FOR_NS lines in a debug log to identify governor limit issues
  • How to identify and resolve a 'Too many SOQL queries: 101' or 'Too many DML statements: 151' error by reading a debug log or test failure message
  • The difference between Metadata API and SFDX (Salesforce CLI) source format for deployment
  • The purpose of the sfdx-project.json file and how it defines package directories, the namespace, and the source API version for a Salesforce DX project
  • How to use Salesforce CLI commands (sf project deploy start, sf project retrieve start) for source-driven deployments
  • How package.xml (manifest) files specify which metadata components to include in a Metadata API deployment or retrieval
  • The purpose of a .forceignore file in a Salesforce DX project and how it controls which metadata is retrieved or deployed
  • The role of scratch orgs in a source-driven development workflow and how they differ from sandboxes for development and testing
  • How to run specified Apex tests during a deployment using the RunSpecifiedTests or RunLocalTests option and the minimum code coverage requirement
  • How to use sf apex run test --synchronous and interpret the test result output including code coverage percentages and failure messages via CLI
  • How Change Sets differ from Salesforce CLI/Metadata API deployments in terms of source control integration and automation capability
  • The difference between unlocked packages and managed packages in namespace requirements, versioning, and subscriber edit rights
  • When to use unlocked packages versus managed packages
  • How to create and install an unlocked package using the Salesforce CLI (sf package create, sf package version create, sf package install) and what artifacts are produced
  • How a CI/CD pipeline using GitHub Actions or GitLab CI integrates with Salesforce DX to authenticate via a connected app JWT and deploy on pull request merge
  • How the number of components on a Lightning page, excessive wire calls, and large data payloads degrade UI performance, and how to mitigate them
  • How caching @AuraEnabled(cacheable=true) Apex results reduces server round trips in LWC wire-based data fetching
  • How lazy loading components using conditional rendering (if:true) versus always rendering hidden components affects initial page load performance in LWC
  • How to use the Chrome DevTools Performance tab and Network panel to diagnose slow LWC rendering and excessive server calls
  • How to use the Lightning Experience Performance page and Salesforce Optimizer to identify slow-loading pages and components
  • How to use SOQL query selectively (indexed fields in WHERE clause) to avoid full table scans and non-selective query errors on large objects
  • Which standard fields are automatically indexed in Salesforce (Id, Name, OwnerId, CreatedDate, external ID fields)
  • How to use the Salesforce query plan tool (Query Plan button in Developer Console) to analyze whether a query will use an index or perform a full table scan
  • How heap size limits in Apex (6 MB synchronous / 12 MB asynchronous) constrain large query results, and the pattern of using SOQL for loops or pagination to stay within limits
  • How to use SOQL for loops (for (SObject s : [SELECT ...]) {}) to process large query results without exceeding heap size limits
  • How to use QueryLocator in batch Apex start() to retrieve up to 50 million records compared to the Iterable approach, and when each is appropriate
  • How to use the Platform Cache (Org Cache and Session Cache) in Apex via Cache.Org.put() / get() to cache expensive query results or computed values across transactions
  • The difference between Org Cache and Session Cache in Platform Cache: scope, TTL, visibility across users, and Apex usage patterns for each
  • How to avoid locking contention and row-lock errors by designing batch jobs and triggers to avoid updating the same parent records concurrently
  • The maximum synchronous callout timeout (120 seconds) versus the benefit of asynchronous callouts for long-running external services
  • How moving an HTTP callout from a synchronous Apex controller method to a @future or Queueable Apex method prevents the user from waiting on the external response
  • How Continuation objects in Visualforce and LWC allow server-side callouts to run asynchronously while the browser remains responsive
  • How to design a utility/service class in Apex with static methods to share common logic across multiple triggers, controllers, and batch classes
  • How to implement an invocable Apex method using @InvocableMethod so it can be called from Flow, Process Builder, and REST API, enabling reuse across channels
  • How to create a reusable LWC base component that encapsulates common UI logic and is composed into multiple parent components
  • How to use Apex interfaces to define contracts between a trigger handler and interchangeable strategy implementations for policy-based reuse
  • Given Apex code with SOQL inside a for-loop, identify the governor limit risk and rewrite the query outside the loop using a Map for lookup
  • Given Apex code with DML inside a for-loop, identify the issue and refactor to collect records in a List and perform a single bulk DML operation
  • Given a SOQL query missing a WHERE clause filter on an indexed field against a large object, identify the non-selective query risk and the correct remediation
  • Given a batch Apex execute() method that queries records instead of processing the scope parameter, identify the inefficiency and the correct pattern
  • Given an LWC that calls multiple @wire-decorated methods for related data, identify when a single server-side Apex method combining data would be more efficient
  • Given Apex code that uses String concatenation in a loop to build a large string, identify the heap size risk and rewrite using a List<String> and String.join()

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How LWC and Aura components subscribe to Platform Events using the lightning/empApi or empApi Aura module

Explainer

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Practice Question

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Next conceptPlatform Event delivery durability and replay ID: how subscribers can replay missed events using a stored ReplayId

Checklist progress

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0 of 197 concepts learned

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Explainer

The empApi module in Lightning Web Components and the empApi component in Aura enable real-time subscription to streaming channels like Platform Events. They utilize a shared CometD connection within a browser session to listen for event messages and trigger callbacks.

Core information
  • LWC developers import methods like subscribe and unsubscribe from the lightning/empApi module, whereas Aura developers add the lightning:empApi component to their markup.
More details and nuances
  • The empApi connection is not shared across different browsers or user sessions, and the limit applies per channel and unique browser session.