🚀 50 JavaScript Interview Questions for 2024 🚀

1.What is JavaScript?
2.What are the data types in JavaScript?
3.What is the difference between null and undefined?
4.Explain the concept of hoisting in JavaScript.
5.What is a closure in JavaScript?
6.What is the difference between “==” and “===” operators in JavaScript?
7.Explain the concept of prototypal inheritance in JavaScript.
8.What are the different ways to define a function in JavaScript?
9.How does event delegation work in JavaScript?
10.What is the purpose of the “this” keyword in JavaScript?
11.What are the different ways to create objects in JavaScript?
12.Explain the concept of callback functions in JavaScript.
13.What is event bubbling and event capturing in JavaScript?
14.What is the purpose of the “bind” method in JavaScript?
15.Explain the concept of AJAX in JavaScript.
16.What is the “typeof” operator used for?
17.How does JavaScript handle errors and exceptions?
18.Explain the concept of event-driven programming in JavaScript.
19.What is the purpose of the “async” and “await” keywords in JavaScript?
20.What is the difference between a deep copy and a shallow copy in JavaScript?
21.How does JavaScript handle memory management?
22.Explain the concept of event loop in JavaScript.
23.What is the purpose of the “map” method in JavaScript?
24.What is a promise in JavaScript?
25.How do you handle errors in promises?
26.Explain the concept of currying in JavaScript.
27.What is the purpose of the “reduce” method in JavaScript?
28.What is the difference between “null” and “undefined” in JavaScript?
29.What are the different types of loops in JavaScript?
30.What is the difference between “let,” “const,” and “var” in JavaScript?
31.Explain the concept of event propagation in JavaScript.
32.What are the different ways to manipulate the DOM in JavaScript?
33.What is the purpose of the “localStorage” and “sessionStorage” objects?
34.How do you handle asynchronous operations in JavaScript?
35.What is the purpose of the “forEach” method in JavaScript?
36.What are the differences between “let” and “var” in JavaScript?
37.Explain the concept of memoization in JavaScript.
38.What is the purpose of the “splice” method in JavaScript arrays?
39.What is a generator function in JavaScript?
40.How does JavaScript handle variable scoping?
41.What is the purpose of the “split” method in JavaScript?
42.What is the difference between a deep clone and a shallow clone of an object?
43.Explain the concept of the event delegation pattern.
44.What are the differences between JavaScript’s “null” and “undefined”?
45.What is the purpose of the “arguments” object in JavaScript?
46.What are the different ways to define methods in JavaScript objects?
47.Explain the concept of memoization and its benefits.
48.What is the difference between “slice” and “splice” in JavaScript arrays?
49.What is the purpose of the “apply” and “call” methods in JavaScript?
50.Explain the concept of the event loop in JavaScript and how it handles asynchronous operations.

SQL Basic PDF Notes

most asked DSA Questions:

Array:
-How is an array sorted using quicksort?
-How do you reverse an array?
-How do you remove duplicates from an array?
-How do you find the 2nd largest number in an unsorted integer array

Linked Lists:
-How do you find the length of a linked list?
-How do you reverse a linked list?
-How do you find the third node from the end?
-How are duplicate nodes removed in an unsorted linked list?

Strings:
-How do you check if a string contains only digits?
-How can a given string be reversed?
-find the first non-repeated character?
-find duplicate characters in strings/

Binary trees:
-How are all leaves of a binary tree printed?
-How do you check if a tree is a binary search tree?
-How is a binary search tree implemented?
-find the lowest common ancestor in binary tree?

Graph:
-How to detect a cycle in a directed graph?
-How to detect a cycle in an undirected graph?
-Find the total number of strongly connected components?
-Find whether a path exists between two nodes of a graph?

Node Js Handwritten Notes💡
https://coderbaba.gumroad.com/l/nodejs

best DSA Resource
https://drive.google.com/drive/folders/14786Md4FyFngju0V5O4GmT_SgN6Wt61j?usp=drive_link

Crack Your SQL Server Interview: 50 Questions Explained & Asked by MANG & FAANG Companies
https://youtu.be/oGhO-6ZB4vw

Crack Your SQL Server Interview: 50 Questions Explained & Asked by MANG & FAANG Companies
https://youtu.be/oGhO-6ZB4vw

Are you preparing for an SQL interview? Here are some essential SQL questions to help you ace your next interview! 👨‍💻📊
🔍 Basic SQL Concepts:
📌 Explain the difference between SQL and NoSQL databases.
📌 What are the common data types in SQL?
📋 Querying:
📌 How do you retrieve all records from a table named "Customers"?
📌 What is the difference between SELECT and SELECT DISTINCT in a query?
📌 Explain the purpose of the WHERE clause in SQL queries.
🔗 Joins:
📌 Describe the types of joins in SQL (INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL JOIN).
📌 How would you retrieve data from two tables using an INNER JOIN?
📊 Aggregate Functions:
📌 What are aggregate functions in SQL? Can you name a few?
📌 How do you calculate the average, sum, and count of a column in a SQL query?
🔍 Grouping and Filtering:
📌 Explain the GROUP BY clause and its use in SQL.
📌 How would you filter the results of an SQL query using the HAVING clause?
🔄 Subqueries:
📌 What is a subquery, and when would you use one in SQL?
📌 Provide an example of a subquery in an SQL statement.
🔧 Indexes and Optimization:
📌 Why are indexes important in a database?
📌 How would you optimize a slow-running SQL query?
📚 Normalization and Data Integrity:
📌 What is database normalization, and why is it important?
📌 How can you enforce data integrity in a SQL database?
⚙️ Transactions:
📌 What is a SQL transaction, and why would you use it?
📌 Explain the concepts of ACID properties in database transactions.
📋 Views and Stored Procedures:
📌 What is a database view, and when would you create one?
📌 What is a stored procedure, and how does it differ from a regular SQL query?
🔥 Advanced SQL:
📌 Can you write a recursive SQL query, and when would you use recursion?
📌 Explain the concept of window functions in SQL.
📌 For more SQL insights and tutorials, follow #coderbaba and stay tuned for more updates! 💡
#SQL #SQLServer #Database #InterviewPreparation #Coding #Programming
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Mastering CHAR, VARCHAR and NVARCHAR Data type in SQL: What 90% of Developers Get Wrong in SQL Server
video Link: https://youtu.be/gwtideAuxSc

👇👇👇download complete PDF notes:👇👇👇👇

Mastering CHAR, VARCHAR and NVARCHAR Data type in SQL: What 90% of Developers Get Wrong in SQL Server
https://youtu.be/gwtideAuxSc
👇👇👇download complete PDF notes:👇👇👇👇

SQL Server Best Practices: Clarifying the Difference Between CHAR, VARCHAR and NVARCHAR
https://youtu.be/gwtideAuxSc

14 Qualities of High-Performing Employees ⭐️💼:
https://youtube.com/shorts/fglhfPpx9Q4

🔍 SQL Server Database Constraints Demystified: Boosting Data Integrity and Efficiency 🔍
Understanding database constraints is pivotal for ensuring robust data integrity and improving efficiency in SQL Server. Here's a quick rundown of the key types of constraints every developer should be familiar with:

📌 Types of Constraints:
1-Default constraint
2-Not Null constraint
3-Primary key constraints
4-Foreign Key constraints
5-Unique Key constraints
6-Check constraint
Implementing the right constraints can significantly enhance the reliability and performance of your database. Stay tuned for more insights and best practices! 🚀
Link: https://youtu.be/7gjPhqpRvB0



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#CoderBaba @coder_baba
#DatabaseConstraints #DataIntegrity #SQLQueries #PrimaryKey #ForeignKey #UniqueKey #CheckConstraint #DatabaseDesign #SQL #DatabaseOptimization #RelationalDatabase #SQL #Database #DataIntegrity #Coding #Programming #TechTips #WebDevelopment
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Become Full Stack Developer in just
steps: 👇👇

Step 1: Learn HTML & CSS
Step 2: Learn Java Script
Step 3: Learn React, Node JS
Step 4: MySql
Step 5: MongoDB
Step 6: Git Commands
Step 7: Build Projects & Push on GitHub
Step 8: Practice, Practice & Practice

🚀 Essential SQL Tips for Beginners! 🚀

Diving into the world of SQL? Here are some vital tips to kickstart your journey and enhance your SQL skills! 👩‍💻👨‍💻

🔹 Primary Key = Unique Key + Not Null constraint 🗝
🔹 Perform case-insensitive search using UPPER() function:
UPPER(customer_name) LIKE 'A%A'
🔹 LIKE operator is for string data types 🧵
🔹 COUNT(*), COUNT(1), COUNT(0) are all equivalent 🧮
🔹 Aggregate functions ignore NULL values 🚫
🔹 MIN, MAX, SUM, AVG, COUNT are for int data types; STRING_AGG is for string data types 📊
🔹 For row-level filtration use WHERE; for aggregate-level filtration use HAVING 🕵️‍♂️
🔹 UNION ALL includes duplicates; UNION excludes duplicates 🔄
🔹 Use UNION ALL if results won't have duplicates 🚫
🔹 Alias the subquery if using columns in the outer select query 📝
🔹 Subqueries can be used with NOT IN condition 🔄
🔹 CTEs are visually better than subqueries; performance-wise they're equivalent 📈
🔹 When joining two tables with one having only one value, use 1=1 for a CROSS JOIN 🤝
🔹 Window functions operate at the ROW level 🪟
🔹 RANK() vs DENSE_RANK(): RANK() skips rank if values are the same 🏅
🔹 EXISTS works on true/false conditions; if the query returns at least one value, the condition is TRUE ✅

👉 If you found these tips helpful, give it a like! 😄
For more insights and updates, follow me and stay tuned!
🌐Link: https://youtu.be/7gjPhqpRvB0
#SQLTips #BeginnerGuide #DatabaseManagement #TechInsights 📚🔍🔥
#CoderBaba #SQLQueries

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