C# & SQL Online Test

About the test:

The C# SQL Test uses scenario-based MCQs to evaluate candidates on their understanding of C# programming language and SQL databases. The test assesses candidates on their knowledge of C# syntax, object-oriented programming (OOP) concepts, and .NET framework, as well as their ability to write and debug C# code. It also evaluates their familiarity with SQL syntax and usage, SQL commands for creating, querying, and modifying relational databases and tables, database design, normalization, and indexing, and their ability to write efficient and optimized SQL queries in C#.

Covered skills:

Types and Variables
Arrays
Functions
Error-handling
Dealing with Null values
Inheritance and Polymorphism
Mult-threading
Memory footprint
Prototype Pattern
File-handling
Generics
Lambda Expressions
LINQ
Memory management
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

Expressions and Operators
Control Statements
Classes, Objects and Methods
Serialization
Object-oriented Programming (OOP)
API development
Garbage Collector
Singletons
Adapter Pattern
Data-streaming
Delegates
Events
Streams
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 C# & SQL Online Test is the most accurate way to shortlist candidates

Reason #1

Tests for on-the-job skills

The C# & SQL Online Test helps recruiters and hiring managers identify qualified candidates from a pool of resumes, and helps in taking objective hiring decisions. It reduces the administrative overhead of interviewing too many candidates and saves time by filtering out unqualified candidates at the first step of the hiring process.

Non-googleable questions & proctoring features enable you to be comfortable with conducting assessments online. The C# & SQL Online Test is ideal for helping recruiters identify which candidates have the skills to do well on the job.

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 C# & SQL Test will be non-googleable.

🧐 Question
Medium Classes and Constructors OOPs	Solve
What is the output of the following C# code?
Easy Arrays and Exceptions Arrays Exceptions	Solve
What is the output of the following C# code?
Medium Multiple Namespaces	Solve
Class Student exists in both firstnamespace and secondnamespace namespaces. Which of the following are the correct ways to use the Student class?
Medium Static and constructors OOPs	Solve
What is the output of the following C# code?
Medium Multi Select	Solve
Consider the following SQL table: How many rows does the following SQL query return?
Medium Select & IN	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?
Hard With, AVG & SUM	Solve
Consider the following SQL table: How many tuples does the following query return?
Easy Registration Queue Logic	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 Longest Road logic hashmaps	Solve
A startup company E-Motors is building driverless automated cars. The car contains a sensor that checks the road quality for the next N meters to decide the optimal speed at which the cars should move. We are given recorded data by the sensor in the form of an array, where each element of the array is the rating given to 1 meter of the road in sequence. The rating given by the sensor is from 1 to 100, where 100 represents the road with the best condition, and any rating above 60 is optimal. Find the longest stretch of road in meters that is categorized as optimal by the sensor. The input is an array of "strings" which needs to be converted from string to integer/number inside the function.
Medium Visitors Count Strings	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 Classes and Constructors OOPs	2 mins C#	Solve
What is the output of the following C# code?
	Easy Arrays and Exceptions Arrays Exceptions	2 mins C#	Solve
What is the output of the following C# code?
	Medium Multiple Namespaces	2 mins C#	Solve
Class Student exists in both firstnamespace and secondnamespace namespaces. Which of the following are the correct ways to use the Student class?
	Medium Static and constructors OOPs	3 mins C#	Solve
What is the output of the following C# code?
	Medium Multi Select	2 mins SQL	Solve
Consider the following SQL table: How many rows does the following SQL query return?
	Medium Select & IN	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?
	Hard With, AVG & SUM	2 mins SQL	Solve
Consider the following SQL table: How many tuples does the following query return?
	Easy Registration Queue Logic	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 Longest Road logic hashmaps	25 mins Coding	Solve
A startup company E-Motors is building driverless automated cars. The car contains a sensor that checks the road quality for the next N meters to decide the optimal speed at which the cars should move. We are given recorded data by the sensor in the form of an array, where each element of the array is the rating given to 1 meter of the road in sequence. The rating given by the sensor is from 1 to 100, where 100 represents the road with the best condition, and any rating above 60 is optimal. Find the longest stretch of road in meters that is categorized as optimal by the sensor. The input is an array of "strings" which needs to be converted from string to integer/number inside the function.
	Medium Visitors Count Strings	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
	Classes and Constructors OOPs	C#	Medium	2 mins	Solve
What is the output of the following C# code?
	Arrays and Exceptions Arrays Exceptions	C#	Easy	2 mins	Solve
What is the output of the following C# code?
	Multiple Namespaces	C#	Medium	2 mins	Solve
Class Student exists in both firstnamespace and secondnamespace namespaces. Which of the following are the correct ways to use the Student class?
	Static and constructors OOPs	C#	Medium	3 mins	Solve
What is the output of the following C# code?
	Multi Select	SQL	Medium	2 mins	Solve
Consider the following SQL table: How many rows does the following SQL query return?
	Select & IN	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?
	With, AVG & SUM	SQL	Hard	2 mins	Solve
Consider the following SQL table: How many tuples does the following query return?
	Registration Queue Logic	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
	Longest Road logic hashmaps	Coding	Medium	25 mins	Solve
A startup company E-Motors is building driverless automated cars. The car contains a sensor that checks the road quality for the next N meters to decide the optimal speed at which the cars should move. We are given recorded data by the sensor in the form of an array, where each element of the array is the rating given to 1 meter of the road in sequence. The rating given by the sensor is from 1 to 100, where 100 represents the road with the best condition, and any rating above 60 is optimal. Find the longest stretch of road in meters that is categorized as optimal by the sensor. The input is an array of "strings" which needs to be converted from string to integer/number inside the function.
	Visitors Count Strings	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 C# & 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 C# & 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 & comparative results

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 C# & SQL Online Test?

Types and Variables

Expressions and Operators

Arrays

Control Statements

Functions

Classes, Objects and Methods

Error-handling

Serialization

Dealing with Null values

Object-oriented Programming (OOP)

Inheritance and Polymorphism

API development

Mult-threading

Garbage Collector

Memory footprint

Singletons

Prototype Pattern

Adapter Pattern

File-handling

Data-streaming

Generics

Delegates

Lambda Expressions

Events

LINQ

Streams

Memory management

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.