30+ OLX Interview Questions and Answers

Design a database schema for a chat application with individual and group messaging.

• Create a 'users' table with unique user IDs

• Create a 'messages' table with message IDs, sender and receiver IDs, message content, and timestamp

• Create a 'groups' table with unique group IDs and group names

• Create a 'group_members' table with group ID and user ID to track group membership

• Use foreign keys to link tables together

• Consider indexing frequently queried columns for performance

SQL query to retrieve all unread messages upon user sign in

• Use a JOIN statement to combine the messages and user tables

• Filter the results to only show messages that have not been read by the user

• Use the user's sign in information to identify which messages are unread

The price of a 2013 Maruti Wagnor with a third owner would depend on various factors.

• The condition of the car will affect the price. A well-maintained car may have a higher price.

• The mileage of the car will also be a factor. A car with lower mileage may have a higher price.

• The demand for the specific model and year of the car in the market will influence the price.

• The location of the sale can also impact the price. Prices may vary in different regions.

• Additional features or m...read more

Our website receives an average of 10,000 unique visitors per day.

• Our website has a steady flow of traffic with a consistent number of unique visitors per day.

• We use Google Analytics to track our web traffic and analyze user behavior.

• Our peak traffic times are during weekdays from 9am to 5pm.

• We have noticed an increase in mobile traffic over the past year.

• Our website's traffic is primarily driven by organic search and social media.

To find missing number in an array of first n numbers.

• Calculate the sum of first n numbers using formula n*(n+1)/2

• Calculate the sum of given array using loop

• Subtract the sum of array from sum of first n numbers to get the missing number

include_once and require_once are PHP functions used to include files. The difference is in how they handle errors.

• include_once will only include the file once, and will not throw a fatal error if the file is not found

• require_once will also only include the file once, but will throw a fatal error if the file is not found

• Both functions are used to include files that contain functions or variables that are needed in the current script

Negotiate based on market value and condition of the car. Provide evidence to support your quote.

• Research the market value of the car and its condition to determine a fair price

• Explain to the customer the factors that affect the value of their car

• Provide evidence such as recent sales of similar cars to support your quote

• Be willing to negotiate and find a compromise that satisfies both parties

Different sources to find and onboard channel partners

• Referrals from existing partners

• Industry events and conferences

• Online directories and marketplaces

• Social media platforms

• Cold outreach and prospecting

• Partner recruitment agencies

• Competitor analysis

• Customer recommendations

Several factors affect the price of a car, including its make and model, age, mileage, condition, features, and market demand.

• Make and model

• Age

• Mileage

• Condition

• Features

• Market demand

Sessions and cookies are both used for maintaining user state, but sessions are server-side and cookies are client-side.

• Sessions store user data on the server, while cookies store data on the client's browser

• Sessions are more secure than cookies because the data is not accessible to the client

• Cookies can be used for tracking user behavior and preferences

• Sessions are typically used for authentication and authorization purposes

• Cookies can be set to expire after a certain amount...read more

Assets can be handled through proper management, distribution, tracking, mapping, allocation, and receiving after user FnF.

• Assets should be properly documented and tracked using a reliable system.

• Distribution should be based on the needs and priorities of the organization.

• Mapping and allocation should be done based on the asset's value and importance.

• After user FnF, assets should be properly received and accounted for.

• Regular audits should be conducted to ensure proper asset ...read more

There are around 15-20 car brands in India.

• Some popular car brands in India are Maruti Suzuki, Hyundai, Tata Motors, Mahindra, Honda, Toyota, and Ford.

• Luxury car brands like Mercedes-Benz, BMW, and Audi also have a presence in India.

• The number of car brands in India is constantly changing with new brands entering the market and some existing ones exiting.

• The Indian government has also been promoting electric vehicles, leading to the entry of brands like MG Motor and Tata Moto...read more

Indexes in MySQL are used to improve query performance by allowing faster data retrieval.

• Indexes are created on one or more columns of a table.

• They work by creating a separate data structure that allows for faster data retrieval.

• Indexes can be created using the CREATE INDEX statement.

• Indexes can also be dropped using the DROP INDEX statement.

• Indexes can be used to speed up SELECT, UPDATE, and DELETE statements.

• Indexes can also be used to enforce uniqueness on a column or set ...read more

Regular communication, understanding dealer's needs, providing value-added services, and incentivizing growth.

• Regularly communicate with the dealer to understand their needs and challenges.

• Provide value-added services such as training, marketing support, and after-sales service.

• Incentivize growth by offering discounts, rebates, or other rewards for meeting sales targets.

• Collaborate with the dealer to develop joint business plans and set achievable goals.

• Monitor performance re...read more

Pre-owned car dealers typically acquire their inventory through trade-ins, auctions, and direct purchases from individuals or other dealers.

• Pre-owned car dealers often acquire inventory through trade-ins from customers looking to upgrade to a new vehicle.

• Dealers may also purchase pre-owned cars at auctions, where they can bid on vehicles from various sources.

• Some dealers may directly purchase pre-owned cars from individuals looking to sell their vehicles, or from other dealer...read more

Being humble to customers involves active listening, showing empathy, and being respectful.

• Listen actively to the customer's needs and concerns

• Show empathy by acknowledging their feelings and experiences

• Be respectful by using polite language and avoiding condescension

• Avoid interrupting or talking over the customer

• Take responsibility for any mistakes or issues and work towards a solution

• Thank the customer for their business and feedback

The ABS system, or Anti-lock Braking System, is a safety feature in vehicles that prevents the wheels from locking up during braking.

• ABS system uses sensors to monitor the rotational speed of each wheel.

• If the system detects that a wheel is about to lock up, it modulates the brake pressure to that wheel.

• This allows the driver to maintain steering control and avoid skidding.

• ABS system is particularly useful in emergency braking situations or on slippery surfaces.

• It is commonly...read more

There are three types of engine smoke: black, white, and blue.

• Black smoke indicates incomplete combustion of fuel.

• White smoke indicates coolant or water in the combustion chamber.

• Blue smoke indicates oil burning in the combustion chamber.

• Examples: A car emitting black smoke may have a clogged air filter, while white smoke may indicate a blown head gasket.

Golden rules of accounting are basic principles that guide the process of recording financial transactions.

• The three golden rules of accounting are: Debit the receiver, Credit the giver; Debit what comes in, Credit what goes out; Debit expenses and losses, Credit income and gains.

• Double-entry accounting system is based on these rules to ensure accuracy and balance in financial records.

• For example, when a company receives cash from a customer, the cash account is debited (incr...read more

I am fluent in English and Spanish.

• Fluent in English and Spanish

• Proficient in reading and writing in French

• Basic knowledge of German

• Experience working with multilingual clients

Promises, async/await, and event emitters are all ways to handle asynchronous operations in JavaScript.

• Promises provide a way to handle asynchronous operations by returning a promise object that can be resolved or rejected.

• Async/await is a syntax for working with promises that makes code easier to read and write.

• Event emitters allow you to create custom events that can be triggered and listened for in your code.

Designation refers to the job title or position held by an employee in an organization.

• Designation is a term used to describe the job title or position held by an employee in an organization.

• It is often used interchangeably with job title.

• Examples of designations include Manager, Executive, Analyst, etc.

My product handling experience has been excellent, with a focus on efficiency and accuracy.

• Implemented efficient product handling processes to streamline operations

• Ensured accurate inventory management and tracking

• Trained team members on proper product handling techniques

• Utilized technology to improve product handling efficiency, such as barcode scanning systems

Design a system like Facebook

• Create a user registration and login system

• Implement a news feed for users to see updates from friends

• Allow users to create and join groups

• Include features like messaging, commenting, and liking posts

• Implement privacy settings for users to control who can see their content

The transmission system is responsible for transferring power from the engine to the wheels of a vehicle.

• The transmission system consists of various components such as the gearbox, clutch, and driveshaft.

• It allows the driver to change gears and control the speed and torque of the vehicle.

• There are different types of transmission systems, including manual, automatic, and continuously variable transmissions.

• For example, in a manual transmission, the driver uses a clutch pedal a...read more

Power steering is a system that assists the driver in turning the wheels of a vehicle.

• Power steering uses hydraulic or electric power to reduce the effort required to steer the vehicle.

• It allows the driver to easily maneuver the vehicle, especially at low speeds or when parking.

• The power steering system consists of a pump, fluid reservoir, hoses, and a steering gear or rack.

• When the driver turns the steering wheel, the power steering pump applies pressure to the fluid, which ...read more

Rank assigns unique ranks to each distinct value, while Dense Rank assigns consecutive ranks to each distinct value.

• Rank does not skip ranks when there are ties, while Dense Rank does

• Rank will have gaps in ranks if there are ties, while Dense Rank will not

• Rank function is used to assign a unique rank to each distinct row, while Dense Rank function is used to assign consecutive ranks to each distinct row

My favorite product is the iPhone. Metrics I would track include user engagement, retention rate, customer satisfaction, and revenue growth.

• User engagement: tracking daily active users, time spent on the device, and frequency of app usage.

• Retention rate: monitoring how many users continue to use the product over time.

• Customer satisfaction: collecting feedback through surveys, reviews, and customer support interactions.

• Revenue growth: analyzing sales data, subscription renewal...read more

I have worked with various payroll software including ADP, Paychex, and QuickBooks.

• ADP

• Paychex

• QuickBooks

The question is asking for a variation of sorting an array containing 0s, 1s, and 2s.

• Use a three-way partitioning algorithm to sort the array in a single pass.

• Keep track of three pointers - low, mid, and high to partition the array.

• Example: Input array = [0, 1, 2, 1, 0], Output array = [0, 0, 1, 1, 2]

A palindromic substring is a string that reads the same forwards and backwards.

• Use dynamic programming to find the longest palindromic substring.

• Start by considering each character as the center of a potential palindrome.

• Expand outwards from each center to check for palindromic substrings.

• Keep track of the longest palindrome found so far.

• Example: Input 'babad', Output 'bab' or 'aba'.

Design a video streaming platform

• Consider the scalability and performance requirements

• Implement a content delivery network (CDN) to distribute video content

• Use adaptive streaming techniques to optimize video quality based on network conditions

• Implement user authentication and authorization mechanisms

• Design a robust video encoding and transcoding system

• Implement a recommendation engine to suggest relevant videos

• Ensure secure video streaming by using encryption and DRM

• Implement...read more