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Total0 / 149
Easy0 / 57
Medium0 / 68
Hard0 / 24
Filtering0/6 solved
1
Employee Name Search
Filtering
AmazonEasy—
2
Employees Earning Over 100K
Filtering
GoogleEasy—
3
Employees Without a Manager
Filtering
AmazonEasy—
4
Low Stock Products
Filtering
AmazonEasy—
5
Orders Above $100
Filtering
StripeEasy—
6
Products Out of Stock
Filtering
AmazonEasy—
Sorting0/8 solved
1
10 Most Recent Orders
Sorting
AmazonEasy—
2
Alphabetical Product Catalog
Sorting
ShopifyEasy—
3
Employees Sorted by Department
Sorting
AmazonEasy—
4
Top 5 Highest-Paid Employees
Sorting
AmazonEasy—
5
Top 5 Longest-Tenured Employees
Sorting
LinkedInEasy—
6
Top 5 Most Expensive Products
Sorting
AmazonEasy—
7
Customers Ranked by Total Spend
Sorting
AmazonMedium—
8
Products Ranked by Price Within Category
Sorting
AmazonMedium—
Distinct0/8 solved
1
Count Products Ordered More Than Once
Distinct
AmazonEasy—
2
Count Unique Customers
Distinct
AmazonEasy—
3
List Product Categories
Distinct
AmazonEasy—
4
List Unique Customer Countries
Distinct
ShopifyEasy—
5
List Unique Job Titles
Distinct
GoogleEasy—
6
Distinct Event Types Per User
Distinct
MetaMedium—
7
Find Duplicate Email Addresses
Distinct
GoogleMedium—
8
Unique Purchasers by Month
Distinct
StripeMedium—
Aggregation0/8 solved
1
Average Employee Salary
Aggregation
AmazonEasy—
2
Count Orders by Status
Aggregation
ShopifyEasy—
3
Min and Max Salary by Department
Aggregation
GoogleEasy—
4
Minimum and Maximum Order Amount
Aggregation
StripeEasy—
5
Total Revenue from Orders
Aggregation
StripeEasy—
6
Total Sales by Region
Aggregation
WalmartEasy—
7
Average Order Value by Customer (Min 3 Orders)Pro
Aggregation
ShopifyMedium—
8
Revenue Concentration by ProductPro
Aggregation
AmazonMedium—
Grouping0/15 solved
1
Average Rating per Product
Grouping
AirbnbEasy—
2
Count Orders by Status
Grouping
DoorDashEasy—
3
Department Headcount
Grouping
AmazonEasy—
4
Find Duplicate Emails
Grouping
GoogleEasy—
5
Highest Paid per Department
Grouping
AmazonEasy—
6
Order Count per Customer
Grouping
AmazonEasy—
7
Product Count per Category
Grouping
AmazonEasy—
8
Top Earning Employees
Grouping
AmazonEasy—
9
Total Items per Order
Grouping
AmazonEasy—
10
User Count by Country
Grouping
AirbnbEasy—
11
Average Order Value per Customer
Grouping
AmazonMedium—
12
Employees with Multiple Roles
Grouping
GoogleMedium—
13
First Purchase Date per Customer
Grouping
AmazonMedium—
14
Salary Statistics by Department
Grouping
AmazonMedium—
15
Top 3 Customers by Total Spend
Grouping
AmazonMedium—
Filtering Groups0/8 solved
1
Active Product Categories
Filtering Groups
WalmartEasy—
2
Customers With Multiple Orders
Filtering Groups
AmazonEasy—
3
High Revenue Products
Filtering Groups
StripeEasy—
4
Customers With Multiple Orders
Filtering Groups
AmazonMedium—
5
Departments Above Average Salary
Filtering Groups
GoogleMedium—
6
Departments With High Average Salary
Filtering Groups
GoogleMedium—
7
Product Categories With Wide Price Range
Filtering Groups
AmazonMedium—
8
Users With Failed Login Attempts
Filtering Groups
CloudflareMedium—
Joins0/11 solved
1
Customers With No Orders
Joins
AmazonEasy—
2
Orders with Customer Name
Joins
AmazonEasy—
3
Products Never Ordered
Joins
AmazonEasy—
4
Average Revenue per User (ARPU)
Joins
StripeMedium—
5
Customer Lifetime Value
Joins
AmazonMedium—
6
Day-1 User Retention
Joins
SpotifyMedium—
7
Employees and Their Managers
Joins
AmazonMedium—
8
Full Inventory and Sales Reconciliation
Joins
AmazonMedium—
9
Order Line Items with Customer and Product
Joins
AmazonMedium—
10
Revenue by Product Category
Joins
AmazonMedium—
11
Frequently Bought TogetherPro
Joins
AmazonHard—
Self Joins0/8 solved
1
Employee and Manager Name Pairs
Self Joins
AmazonEasy—
2
Find Salary Peers in the Same Department
Self Joins
MicrosoftEasy—
3
Direct Reports of a ManagerPro
Self Joins
GoogleMedium—
4
Generate Team Matchups Within DivisionPro
Self Joins
GoogleMedium—
5
Product Price Pairs Within CategoryPro
Self Joins
AmazonMedium—
6
Users With Back-to-Back Login DaysPro
Self Joins
MetaMedium—
7
Employees Earning More Than Their Manager
Self Joins
AmazonHard—
8
Products Frequently Bought Together
Self Joins
AmazonHard—
Subqueries0/6 solved
1
Products Above Average Price
Subqueries
AmazonEasy—
2
Employees Above Company Average Salary
Subqueries
GoogleMedium—
3
Employees Earning Above Department Average
Subqueries
AmazonMedium—
4
Orders Above the Customer's Own Average
Subqueries
AmazonMedium—
5
Products With No Reviews
Subqueries
AmazonMedium—
6
Second Highest Salary
Subqueries
AmazonMedium—
CTEs0/11 solved
1
New vs Returning Customers per Month
CTEs
UberMedium—
2
A/B Test Conversion AnalysisPro
CTEs
AirbnbHard—
3
Full Org Chart via Recursive CTEPro
CTEs
GoogleHard—
4
Funnel Conversion AnalysisPro
CTEs
AirbnbHard—
5
Longest Monthly Ordering Streak per CustomerPro
CTEs
AmazonHard—
6
Monthly Recurring Revenue (MRR)Pro
CTEs
StripeHard—
7
Reactivated Users
CTEs
TwitterHard—
8
Revenue by Customer Signup CohortPro
CTEs
MetaHard—
9
Revenue Rollup by Region and CountryPro
CTEs
UberHard—
10
User Retention by CohortPro
CTEs
MetaHard—
11
Year-over-Year Revenue GrowthPro
CTEs
AmazonHard—
Set Operations0/8 solved
1
All Purchases and Refunds
Set Operations
StripeEasy—
2
Churned Customers
Set Operations
ShopifyEasy—
3
Combine Customer Lists
Set Operations
AmazonEasy—
4
Customers Active on Both Channels
Set Operations
MetaEasy—
5
Combined Employee and Contractor List
Set Operations
AmazonMedium—
6
Multi-Region Product CatalogPro
Set Operations
ShopifyMedium—
7
Products in All Three StoresPro
Set Operations
WalmartMedium—
8
Subscribers Who Are Not CustomersPro
Set Operations
HubSpotMedium—
Window Functions0/26 solved
1
Average Days Between Orders per Customer
Window Functions
DoorDashMedium—
2
Cumulative Revenue by Month
Window Functions
AmazonMedium—
3
Day-over-Day Sales Change
Window Functions
AmazonMedium—
4
Days Between Consecutive Orders per Customer
Window Functions
AmazonMedium—
5
Dense Rank Employees by Salary
Window Functions
AmazonMedium—
6
Month-over-Month Revenue Growth
Window Functions
AmazonMedium—
7
Most Prolific Reviewer per Product Category
Window Functions
AirbnbMedium—
8
Most Recent Order per Customer
Window Functions
AmazonMedium—
9
Product Revenue Share
Window Functions
AmazonMedium—
10
Rank Employees by Salary
Window Functions
AmazonMedium—
11
Repeat Purchasers in Consecutive Months
Window Functions
DoorDashMedium—
12
Running Total of Sales
Window Functions
AmazonMedium—
13
Salary Percentile Rank
Window Functions
GoogleMedium—
14
Salary Quartile Bands
Window Functions
AmazonMedium—
15
Top 2 Products by Revenue per Category
Window Functions
AmazonMedium—
16
Top Product per Category by Revenue
Window Functions
AmazonMedium—
17
3-Day Moving Average of Sales
Window Functions
AmazonHard—
18
First and Last Purchase per Customer
Window Functions
AmazonHard—
19
Last-Touch Marketing AttributionPro
Window Functions
GoogleHard—
20
Longest Daily Login Streak per User
Window Functions
SpotifyHard—
21
Median Salary by Department
Window Functions
GoogleHard—
22
Product Price Change History
Window Functions
AmazonHard—
23
Rolling 7-Day RevenuePro
Window Functions
StripeHard—
24
Salary Percentile Breakdown
Window Functions
GoogleHard—
25
Session Gap Analysis
Window Functions
SpotifyHard—
26
Top Driver per City by Completed Rides
Window Functions
UberHard—
CASE Expressions0/8 solved
1
Employee Performance Rating
CASE Expressions
GoogleEasy—
2
Order Size Label
CASE Expressions
AmazonEasy—
3
Product Availability Status
CASE Expressions
ShopifyEasy—
4
Conditional Customer DiscountPro
CASE Expressions
ShopifyMedium—
5
Customer Segment RevenuePro
CASE Expressions
AmazonMedium—
6
Employee Salary Band Classification
CASE Expressions
AmazonMedium—
7
Sales by QuarterPro
CASE Expressions
AmazonMedium—
8
Pivot Revenue by QuarterPro
CASE Expressions
AmazonHard—
Date Filtering0/3 solved
1
Orders in a Date Range
Date Filtering
AmazonEasy—
2
Orders Placed in the Last 30 Days
Date Filtering
AmazonEasy—
3
Monthly Revenue
Date Filtering
AmazonMedium—
Date Functions0/7 solved
1
Customers Who Signed Up This Year
Date Functions
LinkedInEasy—
2
Customers with No Orders in 90 Days
Date Functions
UberMedium—
3
Employee Tenure in Years
Date Functions
AmazonMedium—
4
Revenue by Quarter
Date Functions
AmazonMedium—
5
Signup Cohort Size by Month
Date Functions
LinkedInMedium—
6
Total Sales by Day of Week
Date Functions
AmazonMedium—
7
Weekly Active Users
Date Functions
SpotifyMedium—
String Functions0/8 solved
1
Customer Count by Email Domain
String Functions
LinkedInEasy—
2
Extract Username from Email
String Functions
SlackEasy—
3
Find Long Product Names
String Functions
ShopifyEasy—
4
Full Name Formatting
String Functions
WorkdayEasy—
5
Normalize Email Addresses
String Functions
HubSpotEasy—
6
Clean Phone NumbersPro
String Functions
TwilioMedium—
7
Extract Domain from URLPro
String Functions
GoogleMedium—
8
Search Product DescriptionsPro
String Functions
AmazonMedium—

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