Quick answers to key questions

Short answers to the technical questions above. For project and team questions, answer from your own experience.

Automation and Lightning

• Workflow criteria, second and third option. The second option (created, and every time it is edited) runs the rule on every save as long as the criteria are true. The third option (created, and any time it is edited to subsequently meet criteria) runs only when the record changes from not meeting the criteria to meeting them, so the rule does not fire again on every edit.
• Drawbacks of Process Builder. It is slower than Flow, gets hard to read and debug when it grows, cannot loop through records, is limited for complex logic, and is retired in favour of Flow.
• Application event and component event (Aura). A component event is handled by the component that fires it or by its parents in the containment hierarchy. An application event is broadcast to every component that listens for it, anywhere on the page.
• Call a Lightning component in a Visualforce page. Use Lightning Out: add apex:includeLightning to the page, call $Lightning.use with an Aura app and then $Lightning.createComponent.
• What is LDS? Lightning Data Service reads and saves a single record without Apex, respects sharing and field-level security, and caches records across components.

Apex

• System.QueryException. It is thrown when a SOQL query fails, for example when you assign a query to a single record variable and the query returns no rows or more than one row. Assign the result to a list, or wrap it in try and catch.
• How to bulkify a trigger. Work on Trigger.new as a collection, never run SOQL or DML inside a loop, use sets and maps to collect Ids and look up results, and do a single DML for the whole list.
• Can a trigger call another trigger? One trigger cannot call another directly, but DML in one trigger can fire the trigger of another object. Salesforce stops the chain at a depth of 16 levels, so control recursion with a static flag.
• Synchronous and asynchronous. Synchronous code runs now while the user waits. Asynchronous code (future, queueable, batch, scheduled) runs in the background with higher limits, for example 60 seconds of CPU time instead of 10, and 12 MB of heap instead of 6 MB.
• Can we call a batch class from a trigger? Technically yes, with Database.executeBatch, but it is risky because only a limited number of batch jobs can be queued or active. Prefer queueable Apex for work started from a trigger.
• Can we pass an sObject to a future method? No. Future methods accept only primitive types and collections of primitives, such as List<Id>. Pass the Ids and query inside the method.
• Common problems in batch Apex. Hitting governor limits inside execute, record locking, callouts without Database.AllowsCallouts, losing variable values between batches without Database.Stateful, and too many jobs in the queue.

Security and data

• Can a permission set make a user read only? No. A permission set can only add permissions. To remove edit access, change the profile, or use a minimal profile and give edit access only to the users who need it through permission sets. A muting permission set inside a permission set group can mute permissions given by other permission sets in the same group.
• How many master-detail relationships can an object have? Up to two.
• Which objects can use the Data Import Wizard? Standard objects such as Accounts, Contacts, Leads, Campaign Members and Solutions, and custom objects.
• What is a dynamic dashboard? A dashboard that runs as the logged-in user, so each person sees only the data they can access.
• SOAP and REST. REST is lightweight, uses HTTP methods and usually JSON, and is stateless. SOAP uses XML only, follows a strict contract described by a WSDL file, and has built-in standards for security and transactions.
• What is view state? The hidden data that a Visualforce page keeps between requests to remember its state. It is limited in size, so reduce it by using transient variables, fewer components and smaller collections.