10+ _VOIS Interview Questions and Answers

To detect and remove a cycle from a linked list, we can use Floyd's Cycle Detection Algorithm.

• Use two pointers, slow and fast, to detect a cycle in the linked list.

• If there is a cycle, the fast pointer will eventually meet the slow pointer.

• Once the cycle is detected, reset one of the pointers and move them at the same pace to find the start of the cycle.

• Remove the cycle by setting the next pointer of the node where the two pointers meet to null.

Collections are data structures used to store multiple values of the same data type.

• Types of collections in Oracle are Associative arrays, Nested tables, and Varrays.

• Associative arrays are indexed by string values, Nested tables are like arrays with no fixed size, and Varrays are like arrays with a fixed size.

• Collections can be used to pass multiple values to a stored procedure or function.

Record is a composite data type that stores related fields together.

• A record is a user-defined data type that contains a group of related data items.

• It is also known as a row or tuple in a table.

• Each field in a record can have a different data type.

• Records are commonly used in PL/SQL to hold query results or to pass data between procedures.

• Example: DECLARE emp_rec employees%ROWTYPE;

• This creates a record variable emp_rec that contains all the columns of the employees table.

Reverse a linkedlist by changing the pointers direction

• Iterate through the linkedlist and change the direction of pointers

• Use three pointers to keep track of current, previous, and next nodes

• Update the head of the linkedlist to point to the last node as the new head

The API-creating process involves designing, developing, testing, documenting, and deploying APIs.

• Design the API by defining endpoints, request/response formats, and authentication methods

• Develop the API using programming languages like Java, frameworks like Spring Boot, and tools like Swagger

• Test the API for functionality, performance, security, and scalability

• Document the API with clear instructions, examples, and usage guidelines

• Deploy the API to a server or cloud platform...read more

Before prod deployment, it is crucial to thoroughly test the changes to ensure they do not negatively impact the system.

• Perform thorough testing of the changes in a staging environment before deploying to production

• Ensure all stakeholders are informed and prepared for the deployment

• Have a rollback plan in case any issues arise during deployment

Procedures are used to perform an action, while functions return a value.

• Procedures do not return values, but can have output parameters

• Functions must return a value and cannot have output parameters

• Procedures can modify data, while functions cannot

• Functions can be used in SQL queries, while procedures cannot

I am comfortable with testing as it allows me to ensure the quality and functionality of the product.

• I have experience in creating test plans and test cases to cover all aspects of the software

• I am proficient in using testing tools and techniques to identify and report bugs

• I enjoy the challenge of finding defects and working with the development team to resolve them

• I am detail-oriented and thorough in my approach to testing

Use a SQL query to retrieve all data from a table

• Use SELECT * FROM table_name to retrieve all data

• Make sure you have the necessary permissions to access the table

• Consider using WHERE clause for specific data retrieval

• Check for any filters or conditions specified in the query

An interface in Java is a reference type, similar to a class, that can contain only constants, method signatures, default methods, static methods, and nested types.

• Interfaces are used to define a contract for classes that implement them.

• Classes can implement multiple interfaces, but can only extend one class.

• Interfaces can be used to achieve abstraction and multiple inheritance in Java.

• Example: interface Shape { void draw(); }

• Example: class Circle implements Shape { public vo...read more

Use a loop to iterate through the string and build a new string in reverse order.

• Create an empty string to store the reversed string.

• Iterate through the original string from the end to the beginning.

• Append each character to the new string.

• Return the reversed string.

To sort an array of strings, use a sorting algorithm like quicksort or mergesort.

• Use a sorting algorithm like quicksort or mergesort to sort the array of strings.

• Implement a comparison function to define the sorting order.

• Consider the time complexity of the sorting algorithm for efficiency.

• Example: Sorting an array of strings alphabetically.

Cycle detection in linked list involves finding if there is a loop in the list.

• Use two pointers approach - slow pointer moves one step at a time, fast pointer moves two steps at a time. If they meet, there is a cycle.

• Floyd's Tortoise and Hare algorithm is commonly used for cycle detection in linked lists.

• Maintain a set to keep track of visited nodes and check if a node is already in the set while traversing the list.