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Apex
Master core programmatic development. Study bulkification, async architectures, and trigger handling schemas frequently requested by top technical recruiters.
AI Overview & Core Concepts
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What is Apex in Salesforce?
Apex is a strongly typed, object-oriented programming language executed on the Salesforce multitenant architecture. It allows developers to build transactional execution flows, DML write procedures, and custom REST integrations directly on the Lightning Platform. Apex compiles into bytecode and runs in a cloud sandbox governed by strict execution limit guardrails.
Core Apex Guardrails
- •Bulkification: Write all database operations and logic to handle collections of up to 200 records in a single execution loop.
- •No DML inside loops: Never place query (SOQL) or commit (DML) commands inside loop iterations to prevent transaction governor limit crashes.
- •Async Processing: Use Batch, Queueable, or @future methods to process heavy workloads in separate, higher-limit background threads.
Before Triggers vs. After Triggers
Runs prior to database saves. Best for field validation and in-memory updates on the triggering records.
Runs post-database saving. Allows accessing system IDs and updating related parent or child records.
Apex Pillars.
Elite Apex developers are evaluated on their ability to build scale-safe logic and handle large data volumes.
Bulkification
Designing logic capable of processing batches of up to 200 records in a single database execution block.
Async Processing
Selecting the correct background execution framework (Queueable, Batch, or @future) to optimize performance.
Platform Safety
Adhering strictly to transaction boundaries, governor limit quotas, and test framework standards.
Core Apex Questions
How do you handle trigger recursion in bulk transactions?
"I use a static boolean variable in a helper class and set it to true when the trigger first executes to block future runs."
A simple static boolean fails during bulk DML updates (e.g. via Data Loader) because records are processed in batches of 200, which resets trigger contexts but retains static variables, causing later batches to be bypassed. A bulk-safe design uses a helper class with a static Set<Id> to track processed record IDs. The handler compares incoming records against the Set, filters out processed items, and runs logic only on new records.
What is the difference between Queueable Apex and future methods?
"Future methods are older and use the @future tag, while Queueable is newer and lets you monitor jobs using a Job ID."
Queueable Apex improves upon future methods by supporting complex parameters (like sObjects or custom classes), returning an AsyncApexJob ID for tracking, and allowing jobs to be chained sequentially (one job triggering another). Future methods only accept primitive data types, cannot be monitored natively via ID in apex, and cannot be chained.
Frequently Asked Questions
What is bulkification in Apex?
When should I use Batch Apex instead of Queueable?
Recommended Next Topics
Continue LearningApex Trigger Guide
Learn trigger frameworks, order of execution, and recursion helper patterns.
Governor Limits Guide
Deep-dive into Salesforce execution quotas and CPU management.
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