10+ TCS Interview Questions and Answers

APEX CPU Limit Exceeded error happens when code consumes too much CPU time. Best practices include optimizing code, reducing loops, and using asynchronous processing.

• Avoid using nested loops and optimize code for better performance

• Use asynchronous processing like @future or Queueable to offload CPU intensive tasks

• Limit the use of SOQL queries inside loops to reduce CPU consumption

SOQL query to fetch description field from Account and reason for inability to filter

• SOQL query: SELECT Description FROM Account

• Description field is not filterable because it is a long text field

• Long text fields cannot be filtered in SOQL queries

The @track decorator in Salesforce is used to track changes to a property in a Lightning web component.

• Used to make a property reactive and trigger re-renders when its value changes

• Not mandatory but recommended for properties that need to be reactive

• Use @track when you want changes to a property to be reflected in the UI

The code will output 'undefined' because variable 'a' is hoisted within the function.

• Variable 'a' is hoisted to the top of the function scope, so when 'console.log(a)' is called, 'a' is undefined.

• To fix this, move the declaration of 'var a=2;' above the 'console.log(a);' statement.

Yes, future methods can be called from a batch class in Salesforce.

• Future methods can be called from batch classes to perform asynchronous processing.

• This can be useful for offloading long-running tasks to future methods to avoid hitting governor limits.

• Example: Calling a future method from a batch class to update records in Salesforce asynchronously.

Mixed DML Exception occurs when DML operations are performed on setup and non-setup objects in a single transaction.

• Occurs when DML operations are performed on both setup and non-setup objects in a single transaction

• Setup objects include User, Profile, PermissionSet, etc.

• Non-setup objects include custom objects, standard objects like Account, Contact, etc.

Dynamic polymorphism is the ability of a single function or method to operate on different types of data.

• Allows a function to behave differently based on the object it is operating on

• Achieved through method overriding in object-oriented programming languages

• Enables code reusability and flexibility in software development

Lifecycle hooks in LWC are methods that allow developers to interact with the component at specific stages of its lifecycle.

• ConnectedCallback - called when a component is inserted into the DOM

• RenderedCallback - called after a component's template has been rendered

• DisconnectedCallback - called when a component is removed from the DOM

Aura components are used in Salesforce to build dynamic web applications with reusable components.

• Create interactive user interfaces

• Enhance user experience with dynamic content

• Enable communication between components

• Leverage event-driven architecture

• Support client-side controller logic

Connected apps in Salesforce allow external applications to integrate with Salesforce using APIs.

• Connected apps are created in Salesforce to establish a secure connection with external applications.

• They use OAuth protocol for authentication and authorization.

• Connected apps define the permissions and access levels for external applications.

• They can be used to integrate third-party applications, such as marketing automation tools or custom web applications.

Visualforce is a framework that allows developers to build custom user interfaces for Salesforce applications.

• Visualforce uses a tag-based markup language similar to HTML.

• Developers can use Visualforce to create custom pages, components, and apps within Salesforce.

• Visualforce pages can include standard Salesforce components like fields, buttons, and links.

• Visualforce allows for dynamic content rendering based on user interactions or data.

• Visualforce can be used to create resp...read more