Archive.org and Wayback Machine often have old Salesforce training workbooks (circa 2018-2020) available as PDFs that are still 90% relevant for core logic.
focuses on rapid web application development. For details, see the Salesforce Apex Developer Guide Oracle APEX Overview Apex Developer Guide - Salesforce apex tutorial pdf
Apex is a strongly-typed, object-oriented programming language. It runs natively on the Salesforce multi-tenant cloud platform. Key characteristics include: Archive
| Feature | Java / C# | Apex | | :--- | :--- | :--- | | | public static void main | No main method. Triggers run via events. | | Database | JDBC / ORM (Hibernate) | Native SOQL (SELECT Id FROM Account) | | Logging | Log4j / Console.WriteLine | System.debug(log) goes to debug logs. | | Memory | Gigabytes | 6-12 MB (very limited) | | Deployment | JAR / EXE / Compile | Change Sets / VS Code / Ant | It runs natively on the Salesforce multi-tenant cloud