HTML/CSS, JavaScript, Ruby, and SQL Online Test
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Sign Up To Use This TestThe HTML/CSS, JavaScript, Ruby, and SQL online test assesses candidates' knowledge across the whole Web stack from HTML, CSS, and JavaScript on the Web front-end over Ruby on the back-end to SQL for data access.
It's an ideal test for pre-employment screening. A good Ruby full stack developer needs to be familiar in a wide range of technologies.
This online test requires candidates to solve coding problems and find and fix bugs in multiple technologies.
Recommended Job Roles
Full-Stack Developer
JavaScript Developer
Ruby Developer
SQL Developer
Web Developer
Sample Candidate Report
Sample Free Questions
Ensure
3min
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Easy
Easy
-
CODE
JavaScript
Error handling
Language
Public
JavaScript
JavaScript is the programming language of HTML and the web. It's an essential skill for any programmer working with websites and web technologies.
Error handling
Error handling is essential for properly implementing recovery procedures from errors present in a software application.
Language
A programmer should use a language as a tool, always taking advantage of language-specific data types and built-in functions.
Public
Public questions (free account) are common interview questions. They are great for practicing, or if you want to filter candidates using the classic problems.
Implement the ensure function so that it throws an error if called without arguments or the argument is undefined. Otherwise it should return the given value.
Students
3min
-
Easy
Easy
-
CODE
SQL
Aggregation
Select
Public
SQL
SQL is the dominant technology for accessing application data. It is increasingly becoming a performance bottleneck when it comes to scalability. Given its dominance, SQL is a crucial skill for all engineers.
Aggregation
An aggregate function is typically used in database queries to group together multiple rows to form a single value of meaningful data. A good programmer should be skilled at using data aggregation functions when interacting with databases.
Select
The SELECT statement is used to select data from a database. It is the most used SQL command.
Public
Public questions (free account) are common interview questions. They are great for practicing, or if you want to filter candidates using the classic problems.
Given the following data definition, write a query that returns the number of students whose first name is John. String comparisons should be case sensitive.
TABLE students id INTEGER PRIMARY KEY, firstName VARCHAR(30) NOT NULL, lastName VARCHAR(30) NOT NULL
Avatar
7min
-
Easy
Easy
-
CODE
HTML/CSS
Borders
Element size
Styling
Public
HTML/CSS
HTML is the standard markup language for creating web pages. It's an essential skill for anyone creating web pages of any complexity.
Borders
Borders can be applied to most HTML elements within the body. This is one of the most used element decorations.
Element size
Setting the size of the elements on a web page is one of the basic things that any web developer or designer should know.
Styling
Styling user interfaces according to the specification is a daily routine for a front-end developer.
Public
Public questions (free account) are common interview questions. They are great for practicing, or if you want to filter candidates using the classic problems.
Every user on your website has an image avatar that is displayed when they post a comment. You want to style these images differently from other images on your site. Add a CSS class named avatar that fulfils the following requirements:
- The avatar's border is rounded, so that it appears as a circle.
- The avatar's width and height are both 150px.
- The avatar has a solid border, has a width of 2px, and be colored gray.
For example, the avatar in the template should look like:
Merge Names
10min
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Easy
Easy
-
CODE
Ruby
Arrays
Public
Ruby
Ruby is a dynamic, reflective, object-oriented, general-purpose programming language. Having a basic familiarity with the programming language used on the job is a prerequisite for quickly getting up to speed.
Arrays
An array is a container of a fixed number of objects of a similar type. It is a fundamental component of most programming languages.
Public
Public questions (free account) are common interview questions. They are great for practicing, or if you want to filter candidates using the classic problems.
Implement the unique_names method. When passed two arrays of names, it will return an array containing the names that appear in either or both arrays. The returned array should have no duplicates.
For example, calling unique_names(["Ava", "Emma", "Olivia"], ["Olivia", "Sophia", "Emma"]) should return an array containing Ava, Emma, Olivia, and Sophia in any order.
Premium Questions
The premium question library contains our unique, hand-crafted questions. We offer a refund if you find any of them answered online.
Questions
Filter, Document Store, Positive Numbers, Greeter, Links, Function Wrapper, Double, Truthy Expressions, Roads, Table of Names, Word Count, Cards, Read First Line, Needle, Ranges, New Folder, Log Patch, Log Patch, Shipping, Loading Bar, Ingredients, Array Search, Read Write Execute, Reorder, Segment, Segment, Hobbies, Numbers to Text, A Tag, Ad, Addition, Article Style, ATM Locations, Authors, Autocomplete, Baby Names, Ban Users, Bank Branches, Blog, Bookmark, Category Tree, Chain Link, Cheapest Product, Christmas Tree, Cities, Confirm, Countries, Crop Ratio, Date Transform, Date Transform, Department Report, Developers, Editor, Employee Manager, Format Table, Height, Hide Button, Hobbies, Hospital Patients, Index Performance, Menu Items, Merge Stock Index, Movies, Movies Live, Projects, Rectangles, Restaurant Menu, Retirees, Sales, SMS Messages, Student Activities, Tasks, Transactions, Youngest Child, iframe, Keywords, Label Color, Link, Loading, Log Parser, Logo, Paragraph, Paragraph, Post Comment, Product Rating, Products, Products, Row Appender, Scale Font Size, Screen Reader, Share Button, Shirts, Snapshot, TestDome Logo, Timesheet, Upload, Username, Username, Vectors, Warehouse, Widgets, Language Teacher, Welfare Organization, Manager Sales, Delete Orders, Validation, Timer, Screen, Data Entry, Email Tables, Student Max Score, Average Salary, Movie Genres, Student Rankings, Auto Show, Ice Cream Flavors, Poll, Breakfast MenuSkills
JavaScriptJavaScript
JavaScript is the programming language of HTML and the web. It's an essential skill for any programmer working with websites and web technologies.
Arrays
An array is a container of a fixed number of objects of a similar type. It is a fundamental component of most programming languages.
Ruby
Ruby is a dynamic, reflective, object-oriented, general-purpose programming language. Having a basic familiarity with the programming language used on the job is a prerequisite for quickly getting up to speed.
Bug fixing
Everyone makes mistakes. A good programmer should be able to find and fix a bug in their or someone else's code.
Language
A programmer should use a language as a tool, always taking advantage of language-specific data types and built-in functions.
Closures
Closures are an important concept in any programming language in which functions are first-class citizens.
HTML/CSS
HTML is the standard markup language for creating web pages. It's an essential skill for anyone creating web pages of any complexity.
CSS selectors
Selectors are a programming pattern that can be used to select an element from a container. They are primarily used in technologies such as CSS and jQuery to apply styles to groups of elements.
Styling
Styling user interfaces according to the specification is a daily routine for a front-end developer.
Exceptions
Exceptions exist in most modern programming languages, making it important for a programmer to understand them and know how to handle them.
DOM manipulation
Dynamically accessing and updating user interface elements is an important part of most modern web applications.
Event handling
Event-based design patterns are very common in modern applications, especially in the development of user interfaces.
SQL
SQL is the dominant technology for accessing application data. It is increasingly becoming a performance bottleneck when it comes to scalability. Given its dominance, SQL is a crucial skill for all engineers.
Conditions
Conditional statements are a feature of most programming and query languages. They allow the programmer to control what computations are carried out based on a Boolean condition.
Views
A database view is a result set that is defined by a stored query, the results of which can can also be queried. As a fundamental and widely used database construct, it's useful for candidates to understand how and when they should be used.
Strings
The string data structure is used to represent text. It is one of the most commonly used data structures. Therefore, every programmer should be skilled at string manipulation.
Stream
A stream is a sequence of data elements made available over time. It is particularly useful for tasks that may benefit from being asynchronous, including tasks such as I/O processing or reading from a file, and as such is important for developers to understand.
Ranges
A range is an immutable sequence of numbers between the start and end. As a core data structure used for flow control in many programming languages, it's important for all developers to be familiar with.
Monkey patching
Monkey Patching is a method of either adding new or overriding existing functionality without the creation of a new type. As such it's an important tool for developers to be familiar with.
Arithmetic
Arithmetic is a fundamental branch of mathematics. An understanding of arithmetic concepts, and their application, is important for every candidate.
HTML5
HTML5 is now supported in all modern browsers, making it important for front-end developers to know how to use its features.
Subqueries
Subqueries are commonly used in database interactions, making it important for a programmer to be skilled at writing them.
Update
The UPDATE statement is used to modify the existing records in a table and is one of the most used operations for working with the database.
Recursion
A good programmer should be familiar with when to use recursive functions, since they can provide elegant solutions for complex problems.
Iteration
Iteration is the act of repeating a process, or cycling through a collection. Iteration is one of the fundamental flow control tools available to developers.
Attribute manipulation
Getting and setting HTML attributes is one of the most common coding tasks of that changes something on a web page.
Element spacing
Setting the margins and padding of the elements on a web page is one of the basic things that any web developer or designer should know.
CSS advanced
Cascading Style Sheets are the styling language of the web. Knowledge about advanced CSS features is required for seasoned front-end developers.
Element size
Setting the size of the elements on a web page is one of the basic things that any web developer or designer should know.
Constraints
Constraints are used to define rules and relationships. They are applied to a dataset. A constraint may take many forms, such as x ≤ 5 in a programming language and a NOT NULL constraint in a SQL table definition.
Create table
The CREATE TABLE statement is used to create a new table in a database. It is an essential command when creating new database.
Database schema
A database schema defines how data is stored in a database. An SQL database uses a schema to define tables consisting of rows and columns that use fixed data types to store data. Formalizing how data is stored is the first step towards building an application or service.
Select
The SELECT statement is used to select data from a database. It is the most used SQL command.
Create index
The CREATE INDEX statement is used to create indexes for tables. Indexes are used to retrieve data from the database more quickly. They are very important for making performant queries.
Performance tuning
The performance of an application or system is important. The responsiveness and scalability of an application are all related to how performant an application is. Each algorithm and query can have a large positive or negative effect on the whole system.
Flexbox
The Flexible Box Layout Module makes it easier to design a flexible responsive layout structure.
Positioning
Dynamic positioning of user interface elements depending on resolution is more important than ever in modern applications, making this important for a front-end developer.
Alter table
The ALTER TABLE statement is used to add, delete, or modify columns and constraints in an existing table. Alter table statements are important for all programmers who have to modify existing schemas.
Elements and attributes
Defining elements and their attributes is the first process in creating an HTML page.
Semantic tags
HTML5 introduced semantic tags, which can greatly improve the level of automated analysis that can be done on documents, as well as improve the readability of HTML.
Bookmarks
A bookmark is a hyperlink that points to a location within a document, which is defined by a name that is assigned to an element. Bookmarks are used when we need to jump to a specific location within a document.
Hash
A hash (or dictionary) is a data type composed of a collection of key-value pairs, where each possible key appears at most once in the collection. It is used when we need to access items by their keys.
Linked list
A linked list is a linear collection of data elements where each element points to the next. It is a data structure consisting of a collection of nodes which together represent a sequence. It is usually used for advanced scenarios where we need fast access to the next element, or when we need to remove an element from anywhere in the collection.
Aggregation
An aggregate function is typically used in database queries to group together multiple rows to form a single value of meaningful data. A good programmer should be skilled at using data aggregation functions when interacting with databases.
Fonts
Setting the font name or size is part of creating any web page.
Dialog box
Dialog box, a small window that pops-up, is a common way for communicating information to the user and prompting them for a response.
Ordering
Knowing how to order data is a common task for every programmer.
Integer division
Integer division is division in which the fractional part (remainder) is discarded. Knowing this is important for optimal implementation of some algorithms and for avoiding common bugs.
Regex
A regular expression (regex) is a special text string for describing a search pattern. It is a common way for extracting data from text.
Insert
Even though most database insert queries are simple, a good programmer should know how to handle more complicated situations like batch inserts.
Left join
LEFT JOIN is one of the ways to merge rows from two tables. We use it when we also want to show rows that exist in one table, but don't exist in the other table.
Objects
An object is a self-contained component which consists of methods and properties to make a particular type of data useful. Knowing how to create objects, and work with them, is an essential part of OOP.
Asynchronous calls
Calling methods asynchronously is a common task for programmers.
Indexes
The proper implementation and use of indexes are important for improving the performance of database queries.
Union
The UNION operator is used to combine the result-set of two or more SELECT statements. It is often used when a report needs to be made based on multiple tables.
Group by
The GROUP BY statement groups rows by some attribute into summary rows. It is a common command when making various reports.
Joins
A normalized database is normally made up of multiple tables. Joins are, therefore, required to query across multiple tables.
Hyperlink
Hyperlink, or simply a link, is a reference to data that the reader can follow by clicking or tapping. There's no web page without a hyperlink.
IFrame
The HTML Inline Frame element (iframe) represents a nested browsing context, embedding another HTML page into the current one. Web developers often use it to display content within other content.
Animation
Animation is the process in which images or objects are manipulated to appear as if they are moving. It's a powerful effect that is important for UI designers to understand and be able to use.
Serialization
Familiarity with data serialization to and from formats such as XML and JSON is important as it is commonly used for interprocess communication
XML
Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. The design goals of XML emphasize simplicity, generality, and usability across the Internet. This is one of the most used formats for exchanging data over the web.
Content manipulation
Adding or modifying content is the most common task when developing dynamic web pages.
JSON
JSON is an open-standard format that uses human-readable text to transmit data objects consisting of attribute-value pairs. It's the most common data format used for asynchronous browser/server communication.
Sorting
Every programmer should be familiar with data-sorting methods, as sorting is very common in data-analysis processes.
Accessibility
Accessibility refers to the design of products, devices, services, or environments for people who experience disabilities. It's important for all designers and developers to know how to optimize for people who experience disabilities.
Forms
Forms provide a method of grouping inputs and collecting user data. As such, they are important for all front end developers.
CSS layout
Cascading Style Sheets are the styling language of the web. For a front-end developer, a knowledge of CSS layouts is required.
Tables
A table stores data as rows and columns. From databases to HTML layouts, as a data structure they are ubiquitous. They are an important structure for developers to understand and know how to use.
Inheritance
In object-oriented programming, inheritance is the mechanism of basing a class upon another class, retaining similar implementation. Inheritance allows programmers to reuse code and is a must know topic for every programmer who works with OOP languages.
OOP
Object-oriented programming is a paradigm based on encapsulating logic and data into objects, which may then contain fields and procedures. Many of the most widely used programming languages are based on OOP, making it a very important concept in modern programming.
SQL CASE
The CASE statement is SQL's control statement. It goes through conditions and returns a value.
CTE
A CTE (Common Table Expression) is a temporary result set that can be referenced within another SELECT, INSERT, UPDATE, or DELETE statement. Recursive CTEs can reference themselves, which enables developers to work with hierarchical data.
Delete
The delete statement is used to delete records in a table and is one of the four basic CRUD functions (create, read, update, and delete) required for working with any persistent storage.
Callback
A callback is a piece of code that can be passed as an argument to another bit of code. It's a very common pattern that has a wide variety of uses, and as such it's important to understand.
Classes
A class is one of the most widely used and primary structures used in object-oriented programming. As such it's important for any developer to have a working knowledge of how to use it.
ECMAScript 2015
ECMAScript 2015 adds a significant number of features to JavaScript, including classes, modules and range based loops. As such it's important for any JavaScript developer to understand.
Borders
Borders can be applied to most HTML elements within the body. This is one of the most used element decorations.
Inline styles
Inline styles are styles that are applied directly on elements. This is one of the ways for applying styles and for some scenarios, such as for email, is the only supported way.
Responsive design
Anyone who works with web should know how to properly implement responsive web design that makes web pages render well on a variety of devices and screen sizes.
Selectors
Selectors are a programming pattern that can be used to select an element from a container. They are primarily used in technologies such as CSS and jQuery to apply styles to groups of elements.
Score Distribution
# of candidates
| 0-33% | |
|---|---|
| 34-66% | |
| 67-100% |
Score