DispatchTrack Interview Questions and Answers

ACID properties are a set of properties that guarantee reliable and consistent transactions in a database system.

• Atomicity ensures that either all operations in a transaction are completed successfully or none at all.

• Consistency ensures that the database remains in a valid state before and after the transaction.

• Isolation ensures that the concurrent execution of transactions results in a system state that would be obtai...read more

Idempotent HTTP requests are requests that can be repeated multiple times without changing the result beyond the initial request.

• Idempotent requests have the same outcome no matter how many times they are executed.

• GET, PUT, and DELETE HTTP methods are typically idempotent.

• POST requests are not idempotent as they can create new resources with each execution.

Expanding the market can be achieved through market research, identifying new target demographics, developing new products or services, and implementing effective marketing strategies.

• Conduct market research to identify potential new markets or untapped segments within the current market.

• Analyze competitors to understand their strategies and identify opportunities for differentiation.

• Develop new products or services th...read more

Create a basic React app with dummy data fetched from a JSON API.

• Set up a new React project using create-react-app

• Create a component to fetch data from a JSON API using fetch or axios

• Display the fetched data in the component

Binary heap is used to implement a priority queue.

• Binary heap is a complete binary tree where each node has a value greater than or equal to its children.

• It can be implemented using arrays, where the parent of node at index i is at index (i-1)/2.

• Insertion and deletion operations have time complexity of O(log n) in a binary heap.

A binary tree can have any number of nodes, but the maximum number of trees with n nodes is 2^n.

• A binary tree can have 0 nodes, 1 node, 2 nodes, or any number of nodes.

• The maximum number of binary trees with n nodes is 2^n.

• For example, a binary tree with 3 nodes can have up to 8 different structures.

Use a SQL query to find the second highest marks in a student database.

• Use the ORDER BY clause to sort the marks in descending order

• Use the LIMIT clause to limit the result to the second row

Program to check if two strings are anagrams

• Create a function that takes in two strings as input

• Remove any spaces and convert both strings to lowercase for consistency

• Sort the characters in both strings and compare if they are equal to determine if they are anagrams

• Example: 'listen' and 'silent' are anagrams