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| # | Title↑ | Topic↑ | Difficulty↑ | Status↑ |
|---|---|---|---|---|
| 1 | Average Employee Salary AmazonMicrosoft | Aggregation | Easy | — |
| 2 | Average Rating per Product AirbnbDoorDashUber | Grouping | Easy | — |
| 3 | Count Orders by Status ShopifyDoorDashLyft | Grouping | Easy | — |
| 4 | Customer Count by Email Domain LinkedInHubSpotSalesforce | String Functions | Easy | — |
| 5 | Customers Who Signed Up This Year UberLinkedInTwitter | Date Functions | Easy | — |
| 6 | Customers With No Orders AmazonMeta | Joins | Easy | — |
| 7 | Department Headcount AmazonGoogle | Grouping | Easy | — |
| 8 | Employee Name Search AmazonMicrosoft | Filtering | Easy | — |
| 9 | Employees Earning Over 100K AmazonGoogle | Filtering | Easy | — |
| 10 | Employees Sorted by Department AmazonMicrosoft | Sorting | Easy | — |
| 11 | Employees Without a Manager AmazonMicrosoft | Filtering | Easy | — |
| 12 | Find Duplicate Emails GoogleMeta | Grouping | Easy | — |
| 13 | Highest Paid per Department AmazonMicrosoftGoogle | Grouping | Easy | — |
| 14 | List Product Categories AmazonShopify | Distinct | Easy | — |
| 15 | Low Stock Products AmazonShopifyWalmart | Filtering | Easy | — |
| 16 | Minimum and Maximum Order Amount AmazonStripe | Aggregation | Easy | — |
| 17 | Order Count per Customer AmazonShopify | Grouping | Easy | — |
| 18 | Orders Above $100 StripeSquarePayPal | Filtering | Easy | — |
| 19 | Orders Placed in the Last 30 Days AmazonShopifyStripe | Date Filtering | Easy | — |
| 20 | Orders in a Date Range AmazonGoogle | Date Filtering | Easy | — |
| 21 | Orders with Customer Name AmazonShopify | Joins | Easy | — |
| 22 | Product Count per Category AmazonShopify | Grouping | Easy | — |
| 23 | Products Above Average Price AirbnbNetflixSpotify | Subqueries | Easy | — |
| 24 | Products Never Ordered AmazonShopify | Joins | Easy | — |
| 25 | Products Out of Stock AmazonShopify | Filtering | Easy | — |
| 26 | Top 5 Longest-Tenured Employees MicrosoftLinkedInWorkday | Sorting | Easy | — |
| 27 | Top 5 Most Expensive Products AmazonShopify | Sorting | Easy | — |
| 28 | Top Earning Employees AmazonMicrosoft | Grouping | Easy | — |
| 29 | Total Items per Order AmazonShopify | Grouping | Easy | — |
| 30 | Total Revenue from Orders AmazonStripe | Aggregation | Easy | — |
| 31 | User Count by Country AirbnbUberTwitter | Grouping | Easy | — |
| 32 | Average Days Between Orders per Customer AmazonDoorDashInstacart | Window Functions | Medium | — |
| 33 | Average Order Value per Customer AmazonShopifyStripe | Grouping | Medium | — |
| 34 | Average Revenue per User (ARPU) StripeAirbnbNetflix | Joins | Medium | — |
| 35 | Combined Employee and Contractor List AmazonMicrosoft | Set Operations | Medium | — |
| 36 | Cumulative Revenue by Month AmazonGoogleStripe | Window Functions | Medium | — |
| 37 | Customer Lifetime Value AmazonShopifyStripe | Joins | Medium | — |
| 38 | Customers With Multiple Orders AmazonMeta | Filtering Groups | Medium | — |
| 39 | Customers with No Orders in 90 Days DoorDashUberLyft | Date Functions | Medium | — |
| 40 | Day-1 User Retention NetflixSpotifyLinkedIn | Joins | Medium | — |
| 41 | Day-over-Day Sales Change AmazonGoogleStripe | Window Functions | Medium | — |
| 42 | Days Between Consecutive Orders per Customer AmazonMetaShopify | Window Functions | Medium | — |
| 43 | Dense Rank Employees by Salary AmazonGoogleMeta | Window Functions | Medium | — |
| 44 | Departments With High Average Salary GoogleMeta | Filtering Groups | Medium | — |
| 45 | Employee Salary Band Classification AmazonMicrosoftGoogle | CASE Expressions | Medium | — |
| 46 | Employee Tenure in Years AmazonMicrosoftGoogle | Date Functions | Medium | — |
| 47 | Employees Above Company Average Salary GoogleMeta | Subqueries | Medium | — |
| 48 | Employees Earning Above Department Average AmazonGoogle | Subqueries | Medium | — |
| 49 | Employees and Their Managers AmazonMicrosoft | Joins | Medium | — |
| 50 | Employees with Multiple Roles MicrosoftGoogleWorkday | Grouping | Medium | — |
| 51 | First Purchase Date per Customer AmazonStripe | Grouping | Medium | — |
| 52 | Full Inventory and Sales Reconciliation AmazonShopify | Joins | Medium | — |
| 53 | Month-over-Month Revenue Growth ShopifyStripeNetflix | Window Functions | Medium | — |
| 54 | Monthly Revenue AmazonStripe | Date Filtering | Medium | — |
| 55 | Most Prolific Reviewer per Product Category AmazonYelpTripAdvisor | Window Functions | Medium | — |
| 56 | Most Recent Order per Customer AmazonMetaShopify | Window Functions | Medium | — |
| 57 | New vs Returning Customers per Month AirbnbUberLyft | CTEs | Medium | — |
| 58 | Order Line Items with Customer and Product AmazonShopify | Joins | Medium | — |
| 59 | Orders Above the Customer's Own Average AmazonMeta | Subqueries | Medium | — |
| 60 | Product Revenue Share AmazonShopifyWalmart | Window Functions | Medium | — |
| 61 | Products With No Reviews AmazonGoogleShopify | Subqueries | Medium | — |
| 62 | Rank Employees by Salary AmazonGoogle | Window Functions | Medium | — |
| 63 | Repeat Purchasers in Consecutive Months DoorDashLyftInstacart | Window Functions | Medium | — |
| 64 | Revenue by Product Category AmazonShopify | Joins | Medium | — |
| 65 | Revenue by Quarter AmazonGoogleStripe | Date Functions | Medium | — |
| 66 | Running Total of Sales AmazonStripe | Window Functions | Medium | — |
| 67 | Salary Percentile Rank AmazonGoogleMeta | Window Functions | Medium | — |
| 68 | Salary Quartile Bands AmazonGoogleMeta | Window Functions | Medium | — |
| 69 | Salary Statistics by Department AmazonMicrosoftGoogle | Grouping | Medium | — |
| 70 | Second Highest Salary AmazonMeta | Subqueries | Medium | — |
| 71 | Signup Cohort Size by Month SpotifyLinkedInTwitter | Date Functions | Medium | — |
| 72 | Top 2 Products by Revenue per Category AmazonShopifyDoorDash | Window Functions | Medium | — |
| 73 | Top 3 Customers by Total Spend AmazonShopify | Grouping | Medium | — |
| 74 | Top Product per Category by Revenue AmazonGoogleShopify | Window Functions | Medium | — |
| 75 | Total Sales by Day of Week AmazonShopifyStripe | Date Functions | Medium | — |
| 76 | Weekly Active Users NetflixSpotifyTwitter | Date Functions | Medium | — |
| 77 | 3-Day Moving Average of Sales AmazonGoogleStripe | Window Functions | Hard | — |
| 78 | A/B Test Conversion Analysis AirbnbUberNetflix | CTEs | Hard | — |
| 79 | Employees Earning More Than Their Manager AmazonMeta | Self Joins | Hard | — |
| 80 | First and Last Purchase per Customer AmazonMetaStripe | Window Functions | Hard | — |
| 81 | Frequently Bought Together AmazonNetflixSpotify | Joins | Hard | — |
| 82 | Full Org Chart via Recursive CTE AmazonMicrosoftGoogle | CTEs | Hard | — |
| 83 | Funnel Conversion Analysis AirbnbUberLinkedIn | CTEs | Hard | — |
| 84 | Last-Touch Marketing Attribution GoogleMetaHubSpot | Window Functions | Hard | — |
| 85 | Longest Daily Login Streak per User SpotifyLinkedInDuolingo | Window Functions | Hard | — |
| 86 | Longest Monthly Ordering Streak per Customer AmazonGoogleMeta | CTEs | Hard | — |
| 87 | Median Salary by Department MicrosoftGoogleMeta | Window Functions | Hard | — |
| 88 | Monthly Recurring Revenue (MRR) StripeNetflixSpotify | CTEs | Hard | — |
| 89 | Pivot Revenue by Quarter AmazonMetaStripe | CASE Expressions | Hard | — |
| 90 | Product Price Change History AmazonShopifyWalmart | Window Functions | Hard | — |
| 91 | Products Frequently Bought Together AmazonMetaShopify | Self-Joins | Hard | — |
| 92 | Reactivated Users SpotifyLinkedInTwitter | CTEs | Hard | — |
| 93 | Revenue Rollup by Region and Country StripeAirbnbUber | CTEs | Hard | — |
| 94 | Revenue by Customer Signup Cohort GoogleMetaStripe | CTEs | Hard | — |
| 95 | Rolling 7-Day Revenue ShopifyStripeAirbnb | Window Functions | Hard | — |
| 96 | Salary Percentile Breakdown MicrosoftGoogleMeta | Window Functions | Hard | — |
| 97 | Session Gap Analysis NetflixSpotifyTwitter | Window Functions | Hard | — |
| 98 | Top Driver per City by Completed Rides DoorDashUberLyft | Window Functions | Hard | — |
| 99 | User Retention by Cohort GoogleMeta | CTEs | Hard | — |
| 100 | Year-over-Year Revenue Growth AmazonGoogleStripe | CTEs | Hard | — |