JavaScript, NodeJS & SQL Online Test

About the test:

The JavaScript, NodeJS & SQL Test uses scenario-based MCQs to evaluate candidates on their proficiency in JavaScript programming language, NodeJS runtime environment, and SQL database. The test assesses candidates' understanding of topics such as event-driven programming, asynchronous programming, middleware, database connections, SQL queries, and database design principles. Candidates are evaluated on their ability to use JavaScript and NodeJS to develop server-side applications, interact with databases, design database schemas, and write optimized and secure SQL queries for data manipulation and retrieval.

Covered skills:

Types and operators
Variables
Arrays
Strings
HTML/ CSS fundamentals
IIFE
ES6
Cookies
Async/Await
Arrows
Destructuring
Session storage
this', 'call', 'bind' keywords
Exception handling
Service workers
NodeJS under-the-hood
Request Response
Handle HTTP requests
NPM
Event Emitter
Streams
CRONs
Serving static files
CORS
Templating engines (Handlebars)
In-memory cache
Asynchronous programming (Async/ Await)
Singletons
Worker threads
API security
SQL Basics
Data Modification Language
CRUD
Subqueries
3 Valued Logic
Window Functions
Aggregate Functions
ORDER BY
Top-Down Design
Entity Relationship Diagram
Database Types
Permission Management
Transactions
Views
Replication
Vertical + Horizontal Scaling
Database Security
Access Control
Letter Coding
Substitution
Non-verbal Reasoning
Business analysis
Programming languages
Basic DBMS concepts
Automation systems
Non-verbal Reasoning

Loops
Functions
Objects
DOM
Closures
OOPs
Math
JSON
Promises
Timers
Local storage
Console
Event handling
Form handling
JavaScript fundamentals
ExpressJS fundamentals
Routing & Controller Methods
Middlewares
ES6
Buffers
Pipes
Express
JSON and XML
Websockets
Session management
Connecting to databases (SQL, Mongoose)
Promises
Authorization and authentication
Clustering
The Relational Model
SQL Functions
Data Query Language
SQL Filtering / WHERE Statement
Indexes
SQL JOINS
Date Filtering and Timestamps
Operator Precedence
GROUP BY
Bottom-Up Design
Normalization
Multi-Table SELECT
Backup Strategies
Data Types
Sharding
Backups
Distributed vs Centralized Databases
SQL Injections
Computer fundamentals
Number Coding
Coding-Decoding Puzzles
SQL concepts
Coding-Decoding
Computer architecture
SOLID principles
Decision making
Problem-solving approach

See all covered skills

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9 reasons why

Adaface JavaScript, NodeJS & SQL Online Test is the most accurate way to shortlist Full Stack Developers

Reason #1

Tests for on-the-job skills

The JavaScript, NodeJS & SQL Test helps recruiters and hiring managers identify qualified candidates from a pool of resumes and take objective hiring decisions. It reduces the administrative overhead of interviewing too many candidates and saves expensive engineering time by filtering out unqualified candidates.

You can use the Adaface JavaScript, NodeJS & SQL Test to screen candidates for the following roles:

Full Stack Developer
JavaScript Developer
Node.js Developer
SQL Developer

Reason #2

No trick questions

Traditional assessment tools use trick questions and puzzles for the screening, which creates a lot of frustration among candidates about having to go through irrelevant screening assessments.

The main reason we started Adaface is that traditional pre-employment assessment platforms are not a fair way for companies to evaluate candidates. At Adaface, our mission is to help companies find great candidates by assessing on-the-job skills required for a role.

Why we started Adaface ->

Reason #3

Non-googleable questions

We have a very high focus on the quality of questions that test for on-the-job skills. Every question is non-googleable and we have a very high bar for the level of subject matter experts we onboard to create these questions. We have crawlers to check if any of the questions are leaked online. If/ when a question gets leaked, we get an alert. We change the question for you & let you know.

These are just a small sample from our library of 10,000+ questions. The actual questions on this JavaScript, NodeJS & SQL Test will be non-googleable.

🧐 Question
Medium Async Await Promises Promises Async-Await	Solve
What will the following code output? A: 24 after 5 seconds and after another 5 seconds, another 24 B: 24 followed by another 24 immediately C: 24 immediately and another 24 after 5 seconds D: After 5 seconds, 24 and 24 E: Undefined F: NaN G: None of these
Medium Bitcoin prices Axios Promises	Solve
Review the following JavaScript code and pick the correct options: Assume that the API returns a successful 200 response code and a JSON object as the response body. What would the value of ‘a’ be after the code is executed?
Medium My Module Scope	Solve
What will the output of the following JavaScript code be?
Medium Promise Resolve Promises Async-Await	Solve
What does the following code output?
Easy Throw, Try, Async Promises Async-Await	Solve
What does the following JS code output?
Medium I/O cycle and main module Event Loop	Solve
Review the following NodeJS code: Pick the correct statements: A: X will be logged after Y always B: Y will be logged after X always C: The order of executing timeout and immediate callbacks is non-deterministic and is bound by the performance of the process D: In this case, the function calls are scheduled in the main module and not in the I/O cycle E: In this case, the function calls are scheduled in the I/O cycle so setImmediate is always executed before any timers scheduled in the I/O phase, independently of how many timers are left
Easy Res methods	Solve
If none of the methods (res.download, res.end, res.json, res.jsonp, res.redirect, res.render, res.send, res.sendFile, res.sendStatus) are called from a route handler to terminate request response cycle, what happens to the the client request? A) Will be left hanging indefinitely B) Will get an internal server error - 500 C) Will get a service unavailable error - 503 D) Will be left hanging for a while and then request timeout error - 408
Medium Phases and Timers Event Loop	Solve
Review the following NodeJS code: Pick the correct statements: A: Adaface will be logged after Lovelace. B: Lovelace will be logged after Adaface. C: Once the asyncOpThatTakes195ms completes reading the file, it starts executing the callback which takes 10 seconds. Only after this is finished, the event loop will execute the timers that are finished. So the timeout call back will actually be executed after 205 ms even though it is scheduled to be run after 200 ms D: Once the asyncOpThatTakes195ms completes reading the file, it starts executing the callback. While executing the callback, the scheduled timer becomes ready to be executed. So the runtime executes the timer and then completes processing the callback.
Medium Multi Select JOIN GROUP BY	Solve
Consider the following SQL table: How many rows does the following SQL query return?
Medium nth highest sales Nested queries User Defined Functions	Solve
Consider the following SQL table: Which of the following SQL commands will find the ‘nth highest Sales’ if it exists (returns null otherwise)?
Medium Select & IN Nested queries	Solve
Consider the following SQL table: Which of the following SQL queries would return the year when neither a football or cricket winner was chosen?
Medium Sorting Ubers Nested queries Join Comparison operators	Solve
Consider the following SQL table: What will be the first two tuples resulting from the following SQL command?
Hard With, AVG & SUM MAX() MIN() Aggregate functions	Solve
Consider the following SQL table: How many tuples does the following query return?
Easy Registration Queue Logic Queues	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
Medium Visitors Count Strings Logic	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

	🧐 Question	🔧 Skill
	Medium Async Await Promises Promises Async-Await	2 mins JavaScript	Solve
What will the following code output? A: 24 after 5 seconds and after another 5 seconds, another 24 B: 24 followed by another 24 immediately C: 24 immediately and another 24 after 5 seconds D: After 5 seconds, 24 and 24 E: Undefined F: NaN G: None of these
	Medium Bitcoin prices Axios Promises	2 mins JavaScript	Solve
Review the following JavaScript code and pick the correct options: Assume that the API returns a successful 200 response code and a JSON object as the response body. What would the value of ‘a’ be after the code is executed?
	Medium My Module Scope	2 mins JavaScript	Solve
What will the output of the following JavaScript code be?
	Medium Promise Resolve Promises Async-Await	2 mins JavaScript	Solve
What does the following code output?
	Easy Throw, Try, Async Promises Async-Await	2 mins JavaScript	Solve
What does the following JS code output?
	Medium I/O cycle and main module Event Loop	2 mins NodeJS	Solve
Review the following NodeJS code: Pick the correct statements: A: X will be logged after Y always B: Y will be logged after X always C: The order of executing timeout and immediate callbacks is non-deterministic and is bound by the performance of the process D: In this case, the function calls are scheduled in the main module and not in the I/O cycle E: In this case, the function calls are scheduled in the I/O cycle so setImmediate is always executed before any timers scheduled in the I/O phase, independently of how many timers are left
	Easy Res methods	3 mins NodeJS	Solve
If none of the methods (res.download, res.end, res.json, res.jsonp, res.redirect, res.render, res.send, res.sendFile, res.sendStatus) are called from a route handler to terminate request response cycle, what happens to the the client request? A) Will be left hanging indefinitely B) Will get an internal server error - 500 C) Will get a service unavailable error - 503 D) Will be left hanging for a while and then request timeout error - 408
	Medium Phases and Timers Event Loop	2 mins NodeJS	Solve
Review the following NodeJS code: Pick the correct statements: A: Adaface will be logged after Lovelace. B: Lovelace will be logged after Adaface. C: Once the asyncOpThatTakes195ms completes reading the file, it starts executing the callback which takes 10 seconds. Only after this is finished, the event loop will execute the timers that are finished. So the timeout call back will actually be executed after 205 ms even though it is scheduled to be run after 200 ms D: Once the asyncOpThatTakes195ms completes reading the file, it starts executing the callback. While executing the callback, the scheduled timer becomes ready to be executed. So the runtime executes the timer and then completes processing the callback.
	Medium Multi Select JOIN GROUP BY	2 mins SQL	Solve
Consider the following SQL table: How many rows does the following SQL query return?
	Medium nth highest sales Nested queries User Defined Functions	3 mins SQL	Solve
Consider the following SQL table: Which of the following SQL commands will find the ‘nth highest Sales’ if it exists (returns null otherwise)?
	Medium Select & IN Nested queries	3 mins SQL	Solve
Consider the following SQL table: Which of the following SQL queries would return the year when neither a football or cricket winner was chosen?
	Medium Sorting Ubers Nested queries Join Comparison operators	3 mins SQL	Solve
Consider the following SQL table: What will be the first two tuples resulting from the following SQL command?
	Hard With, AVG & SUM MAX() MIN() Aggregate functions	2 mins SQL	Solve
Consider the following SQL table: How many tuples does the following query return?
	Easy Registration Queue Logic Queues	30 mins Coding	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
	Medium Visitors Count Strings Logic	30 mins Coding	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

	🧐 Question	🔧 Skill	💪 Difficulty	⌛ Time
	Async Await Promises Promises Async-Await	JavaScript	Medium	2 mins	Solve
What will the following code output? A: 24 after 5 seconds and after another 5 seconds, another 24 B: 24 followed by another 24 immediately C: 24 immediately and another 24 after 5 seconds D: After 5 seconds, 24 and 24 E: Undefined F: NaN G: None of these
	Bitcoin prices Axios Promises	JavaScript	Medium	2 mins	Solve
Review the following JavaScript code and pick the correct options: Assume that the API returns a successful 200 response code and a JSON object as the response body. What would the value of ‘a’ be after the code is executed?
	My Module Scope	JavaScript	Medium	2 mins	Solve
What will the output of the following JavaScript code be?
	Promise Resolve Promises Async-Await	JavaScript	Medium	2 mins	Solve
What does the following code output?
	Throw, Try, Async Promises Async-Await	JavaScript	Easy	2 mins	Solve
What does the following JS code output?
	I/O cycle and main module Event Loop	NodeJS	Medium	2 mins	Solve
Review the following NodeJS code: Pick the correct statements: A: X will be logged after Y always B: Y will be logged after X always C: The order of executing timeout and immediate callbacks is non-deterministic and is bound by the performance of the process D: In this case, the function calls are scheduled in the main module and not in the I/O cycle E: In this case, the function calls are scheduled in the I/O cycle so setImmediate is always executed before any timers scheduled in the I/O phase, independently of how many timers are left
	Res methods	NodeJS	Easy	3 mins	Solve
If none of the methods (res.download, res.end, res.json, res.jsonp, res.redirect, res.render, res.send, res.sendFile, res.sendStatus) are called from a route handler to terminate request response cycle, what happens to the the client request? A) Will be left hanging indefinitely B) Will get an internal server error - 500 C) Will get a service unavailable error - 503 D) Will be left hanging for a while and then request timeout error - 408
	Phases and Timers Event Loop	NodeJS	Medium	2 mins	Solve
Review the following NodeJS code: Pick the correct statements: A: Adaface will be logged after Lovelace. B: Lovelace will be logged after Adaface. C: Once the asyncOpThatTakes195ms completes reading the file, it starts executing the callback which takes 10 seconds. Only after this is finished, the event loop will execute the timers that are finished. So the timeout call back will actually be executed after 205 ms even though it is scheduled to be run after 200 ms D: Once the asyncOpThatTakes195ms completes reading the file, it starts executing the callback. While executing the callback, the scheduled timer becomes ready to be executed. So the runtime executes the timer and then completes processing the callback.
	Multi Select JOIN GROUP BY	SQL	Medium	2 mins	Solve
Consider the following SQL table: How many rows does the following SQL query return?
	nth highest sales Nested queries User Defined Functions	SQL	Medium	3 mins	Solve
Consider the following SQL table: Which of the following SQL commands will find the ‘nth highest Sales’ if it exists (returns null otherwise)?
	Select & IN Nested queries	SQL	Medium	3 mins	Solve
Consider the following SQL table: Which of the following SQL queries would return the year when neither a football or cricket winner was chosen?
	Sorting Ubers Nested queries Join Comparison operators	SQL	Medium	3 mins	Solve
Consider the following SQL table: What will be the first two tuples resulting from the following SQL command?
	With, AVG & SUM MAX() MIN() Aggregate functions	SQL	Hard	2 mins	Solve
Consider the following SQL table: How many tuples does the following query return?
	Registration Queue Logic Queues	Coding	Easy	30 mins	Solve
We want to register students for the next semester. All students have a receipt which shows the amount pending for the previous semester. A positive amount (or zero) represents that the student has paid extra fees, and a negative amount represents that they have pending fees to be paid. The students are in a queue for the registration. We want to arrange the students in a way such that the students who have a positive amount on the receipt get registered first as compared to the students who have a negative amount. We are given a queue in the form of an array containing the pending amount. For example, if the initial queue is [20, 70, -40, 30, -10], then the final queue will be [20, 70, 30, -40, -10]. Note that the sequence of students should not be changed while arranging them unless required to meet the condition. ⚠️⚠️⚠️ Note: - The first line of the input is the length of the array. The second line contains all the elements of the array. - The input is already parsed into an array of "strings" and passed to a function. You will need to convert string to integer/number type inside the function. - You need to "print" the final result (not return it) to pass the test cases. For the example discussed above, the input will be: 5 20 70 -40 30 -10 Your code needs to print the following to the standard output: 20 70 30 -40 -10
	Visitors Count Strings Logic	Coding	Medium	30 mins	Solve
A manager hires a staff member to keep a record of the number of men, women, and children visiting the museum daily. The staff will note W if any women visit, M for men, and C for children. You need to write code that takes the string that represents the visits and prints the count of men, woman and children. The sequencing should be in decreasing order. Example: Input: WWMMWWCCC Expected Output: 4W3C2M Explanation: ‘W’ has the highest count, then ‘C’, then ‘M’. ⚠️⚠️⚠️ Note: - The input is already parsed and passed to a function. - You need to "print" the final result (not return it) to pass the test cases. - If the input is- “MMW”, then the expected output is "2M1W" since there is no ‘C’. - If any of them have the same count, the output should follow this order - M, W, C.

Reason #4

1200+ customers in 75 countries

With Adaface, we were able to optimise our initial screening process by upwards of 75%, freeing up precious time for both hiring managers and our talent acquisition team alike!

Brandon Lee, Head of People, Love, Bonito

Reason #5

Designed for elimination, not selection

The most important thing while implementing the pre-employment JavaScript, NodeJS & SQL Test in your hiring process is that it is an elimination tool, not a selection tool. In other words: you want to use the test to eliminate the candidates who do poorly on the test, not to select the candidates who come out at the top. While they are super valuable, pre-employment tests do not paint the entire picture of a candidate’s abilities, knowledge, and motivations. Multiple easy questions are more predictive of a candidate's ability than fewer hard questions. Harder questions are often "trick" based questions, which do not provide any meaningful signal about the candidate's skillset.

Reason #6

1 click candidate invites

Email invites: You can send candidates an email invite to the JavaScript, NodeJS & SQL Test from your dashboard by entering their email address.

Public link: You can create a public link for each test that you can share with candidates.

API or integrations: You can invite candidates directly from your ATS by using our pre-built integrations with popular ATS systems or building a custom integration with your in-house ATS.

Reason #7

Detailed scorecards & benchmarks

Reason #8

High completion rate

Adaface tests are conversational, low-stress, and take just 25-40 mins to complete.

This is why Adaface has the highest test-completion rate (86%), which is more than 2x better than traditional assessments.

Reason #9

Advanced Proctoring

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What topics are covered in the JavaScript, NodeJS & SQL Online Test?

Types and operators

Loops

Variables

Functions

Arrays

Objects

Strings

DOM

HTML/ CSS fundamentals

Closures

IIFE

OOPs

ES6

Math

JSON

Async/Await

Promises

Arrows

Timers

Destructuring

Local storage

Session storage

Console

this', 'call', 'bind' keywords

Event handling

Exception handling

Form handling

Service workers

JavaScript fundamentals

NodeJS under-the-hood

ExpressJS fundamentals

Request Response

Routing & Controller Methods

Handle HTTP requests

Middlewares

NPM

ES6

Event Emitter

Buffers

Streams

Pipes

CRONs

Express

Serving static files

JSON and XML

CORS

Websockets

Templating engines (Handlebars)

Session management

In-memory cache

Connecting to databases (SQL, Mongoose)

Asynchronous programming (Async/ Await)

Promises

Singletons

Authorization and authentication

Worker threads

Clustering

API security

The Relational Model

SQL Basics

SQL Functions

Data Modification Language

Data Query Language

CRUD

SQL Filtering / WHERE Statement

Subqueries

Indexes

3 Valued Logic

SQL JOINS

Window Functions

Date Filtering and Timestamps

Aggregate Functions

Operator Precedence

ORDER BY

GROUP BY

Top-Down Design

Bottom-Up Design

Entity Relationship Diagram

Normalization

Database Types

Multi-Table SELECT

Permission Management

Backup Strategies

Transactions

Data Types

Views

Sharding

Replication

Backups

Vertical + Horizontal Scaling

Distributed vs Centralized Databases

Database Security

SQL Injections

Access Control

Computer fundamentals

Letter Coding

Number Coding

Substitution

Coding-Decoding Puzzles

Non-verbal Reasoning

SQL concepts

Business analysis

Coding-Decoding

Programming languages

Computer architecture

Basic DBMS concepts

SOLID principles

Automation systems

Decision making

Non-verbal Reasoning

Problem-solving approach

Preview this test

View sample scorecard

The hiring managers felt that through the technical questions that they asked during the panel interviews, they were able to tell which candidates had better scores, and differentiated with those who did not score as well. They are highly satisfied with the quality of candidates shortlisted with the Adaface screening.

85%

reduction in screening time

View Full Case Study

FAQs

Can I combine multiple skills into one custom assessment?

Yes, absolutely. Custom assessments are set up based on your job description, and will include questions on all must-have skills you specify.

Do you have any anti-cheating or proctoring features in place?

We have the following anti-cheating features in place:

Non-googleable questions
IP proctoring
Web proctoring
Webcam proctoring
Plagiarism detection
Secure browser

Read more about the proctoring features.

How do I interpret test scores?

The primary thing to keep in mind is that an assessment is an elimination tool, not a selection tool. A skills assessment is optimized to help you eliminate candidates who are not technically qualified for the role, it is not optimized to help you find the best candidate for the role. So the ideal way to use an assessment is to decide a threshold score (typically 55%, we help you benchmark) and invite all candidates who score above the threshold for the next rounds of interview.

What experience level can I use this test for?

Each Adaface assessment is customized to your job description/ ideal candidate persona (our subject matter experts will pick the right questions for your assessment from our library of 10000+ questions). This assessment can be customized for any experience level.

Does every candidate get the same questions?

Yes, it makes it much easier for you to compare candidates. Options for MCQ questions and the order of questions are randomized. We have anti-cheating/ proctoring features in place. In our enterprise plan, we also have the option to create multiple versions of the same assessment with questions of similar difficulty levels.