Apex Salesforce Study Notes

Apex Best Practices

The core disciplines — bulkification, selective SOQL, and layered architecture — that keep Apex code safe at production scale.

Apex Data Types

An overview of Apex's primitive types, collection types (List, Set, Map), sObjects and IDs, and the rules governing type conversion and null handling.

Apex Design Patterns

Explore the Trigger Handler, Service Layer, Selector, and Unit of Work patterns that keep large Apex codebases maintainable, testable, and bulk-safe.

Apex Interview Questions

The governor-limit, OOP, and async Apex scenarios interviewers actually probe, with the reasoning strong answers demonstrate.

Apex Quick Reference

A fast lookup for Apex collection syntax, SOQL/DML statement forms, and the exact governor limit numbers that matter day-to-day.

Apex REST and Web Services

Learn how to expose custom REST endpoints with @RestResource, handle request/response payloads, and make outbound callouts to external web services.

Apex Syntax and Variables

Covers the foundational rules of Apex syntax, how to declare and scope variables, naming conventions, and how comments structure readable code.

Apex Triggers Basics

An introduction to what Apex triggers are, how their syntax and events work, and when to reach for a trigger instead of declarative automation.

Batch Apex

Learn how to process millions of records safely using the Database.Batchable interface, controlling chunk size, state, and job chaining.

Building a Trigger Handler

How to structure a one-trigger-per-object handler class with context-specific methods, recursion guards, and safe use of Trigger context variables.

Bulkification and Best Practices

How to write Apex trigger logic that stays safely within governor limits regardless of whether it processes one record or two hundred.

Common Apex Pitfalls

The recurring bugs — unbulkified loops, hardcoded Ids, recursive triggers, and swallowed exceptions — that cause most Apex production incidents.

Conditionals and Loops in Apex

Learn how Apex controls program flow with if/else branching, switch statements, and for/while loops, including the governor limits that shape how you write the…

Exception Handling in Apex

Learn how to use try/catch/finally, built-in and custom exception types, and partial-success DML patterns to write resilient Apex code.

Future Methods and Async Apex

Learn how @future methods let Apex defer work to a separate asynchronous transaction with its own governor limits, and when to reach for them over other async…

Governor Limits

Understand why Salesforce enforces per-transaction governor limits and how to write bulk-safe Apex that never hits SOQL, DML, CPU, or heap ceilings.

Integrating Apex with LWC

Learn how Lightning Web Components call Apex with @AuraEnabled methods, wire adapters, imperative calls, caching, and error handling patterns.

Lists, Sets, and Maps

Master Apex's three core collection types — ordered Lists, unique Sets, and key-value Maps — and when to use each for bulk-safe, governor-limit-friendly code.

Queueable and Scheduled Apex

Learn how Queueable Apex overcomes future method limitations with chaining and sObject support, and how Scheduled Apex runs jobs on a cron-based cadence.

Security and Sharing in Apex

Learn how CRUD/FLS enforcement, sharing keywords, and the WITH SECURITY_ENFORCED / stripInaccessible tools keep Apex code from leaking data users shouldn't see.

sObjects and DML

Understand Apex's sObject data model and the insert, update, upsert, and delete DML operations used to change Salesforce records, including bulk patterns and e…

SOQL Queries

Learn Salesforce Object Query Language (SOQL) syntax for retrieving records, including relationship queries, aggregate functions, and governor-limit-aware quer…

SOSL Searches

Learn Salesforce Object Search Language (SOSL) for full-text search across multiple objects and fields at once, and when to reach for it instead of SOQL.

Testing Apex Code

Learn how to write robust Apex test classes, use assertions and mocks, and produce meaningful code coverage that survives real deployments.