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Start broad, then focus when you want structure.
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Tesla
Foundations Track
Weekly Queue Ratings
Customer support reviews are logged by queue. For reviews submitted in March 2024, return the week_start date, queue_name, and average satisfaction_score rou...
Foundations Track
Trainer Certification Coverage
The operations team needs trainers who can cover every required warehouse course. Return the trainer_id values for trainers who hold all three certifications...
Spotify
Foundations Track
Sponsor Payback Ratio
Finance wants a simple efficiency metric for podcast sponsors. For each sponsor_id, return the ratio of total attributed_revenue to total media_spend rounded...
DoorDash
Foundations Track
Stockout Days by Warehouse
The inventory team wants to know which warehouses experienced stockouts in July 2024. Return warehouse_id and the number of stockout_days where units_on_hand...
Foundations Track
Tutor Utilization by Subject
Learning ops wants a utilization view for tutoring capacity. Return each subject and the utilization_pct rounded to two decimals, calculated as total booked_...
Salesforce
Foundations Track
Partner Contracts Expiring Soon
Partnership ops wants a list of non-renewing contracts that are about to end. Using 2024-11-01 as the reference date, return partner_id, region, and end_date...
DoorDash
Foundations Track
Duplicate Delivery Role Posts
Delivery operations wants a monthly cleanup report for employers that recycled the same role posting. Looking only at April 2024, return one value named empl...
PayPal
Foundations Track
Final Wallet Balance
For each account_id, calculate the final wallet balance. Credits add to the balance and debits subtract from it. Return account_id and final_balance ordered ...
Netflix
Foundations Track
Streaming Device View Mix
The streaming analytics team wants a one-row device-family snapshot for recent viewing traffic. Count laptop events separately, roll phone and tablet into a ...
Airbnb
Foundations Track
Top Rated Venues
Return the top two venue_id values with the highest average star rating, considering only venues that have at least three reviews. Output venue_id and avg_st...
Foundations Track
Advertiser Health Status
Classify each advertiser based on month-over-month spend. Return advertiser_id and status using these rules: New if previous_month_spend is 0 and current_mon...
Wayfair
Foundations Track
Complete Skill Coverage
At Wayfair, analysts are preparing a scorecard focused on complete skill coverage. Return the candidate_id values for candidates who have all three required ...
Salesforce
Foundations Track
Alternating Measurement Totals
Salesforce wants a scorecard for alternating measurement totals. Return separate totals for odd-numbered and even-numbered measurement days. Return two colum...
Wayfair
Foundations Track
Pages Without Followers
At Wayfair, analysts are preparing a scorecard focused on pages without followers. Return every page_id that has no follower rows. Sort by page_id.
Netflix
Foundations Track
Device View Mix
Netflix is reviewing device view mix through a scorecard. Count how many views came from laptop devices and how many came from mobile devices. Treat phone an...
Meta
Foundations Track
Third Customer Transaction
Meta wants a scorecard for third customer transaction. Return each user_id and transaction_date for the third transaction made by that user. Sort by user_id.
Amazon
Foundations Track
Departments Above Average Pay
Use this Amazon scorecard to work on departments above average pay. Return each department_id whose average salary exceeds the company average salary for Mar...
Databricks
Foundations Track
Most Frequent Item Counts
Databricks wants a scorecard for most frequent item counts. Return the item_count value or values with the highest order_occurrences. Sort by item_count.
TikTok
Foundations Track
First Customer Transaction
TikTok is reviewing first customer transaction through a scorecard. Return each user_id and transaction_date for the first transaction made by that user. Sor...
Snowflake
Foundations Track
Late Shipment Rate By Carrier
Snowflake is reviewing late shipment rate by carrier through a scorecard. Return the percentage of shipments that arrived late by carrier_name. Output carrie...
Foundations Track
Creators With Multiple 2024 Posts
Use this Pinterest scorecard to work on creators with multiple 2024 posts. Return each creator_id that posted at least two items in 2024. Sort by creator_id.
TikTok
Foundations Track
2024 App Click Volume
TikTok wants a scorecard for 2024 app click volume. Return each app_id and the total number of click events recorded in 2024. Sort by app_id.
Apple
Foundations Track
Duplicate Job Posts
Apple wants a scorecard for duplicate job posts. Return the number of employers that posted the same role_name in the same city more than once during April 2...
Salesforce
Foundations Track
Customers Sharing Same
Salesforce is reviewing customers sharing same through a scorecard. Return each customer pair that purchased the same order on the same day. Output customer_...
Visa
Foundations Track
Median Google Search Frequency
At Visa, analysts are preparing a scorecard focused on median google search frequency. Return the weighted median number of searches from the compressed sear...
TikTok
Foundations Track
Frequent Support Callers
Use this TikTok scorecard to work on frequent support callers. Return the distinct policy_holder_id values for members who made at least 3 calls. Sort by pol...
Foundations Track
Highest Profit Drugs
LinkedIn wants a scorecard for highest profit drugs. Return the top 3 drugs by total profit. Output drug and total_profit sorted from highest to lowest profit.
Tesla
Foundations Track
Manufacturer Sales In Millions
At Tesla, analysts are preparing a scorecard focused on manufacturer sales in millions. Return the total sales per manufacturer rounded to the nearest millio...
Tesla
Foundations Track
Top Product By Category
Tesla is reviewing top product by category through a trend check. Return the highest-grossing product_id in each category during June 2024 along with categor...
Visa
Foundations Track
Bidirectional Transfer Pairs
Visa is reviewing bidirectional transfer pairs through a trend check. Count unique transfer relationships regardless of direction. Return relationship_count.
Alibaba
Foundations Track
Second-highest Salary
Alibaba wants a readout for second-highest salary. Return the second-highest salary amount in the table as second_highest_salary.
Wayfair
Foundations Track
Signup Confirmation Rate
At Wayfair, analysts are preparing a operations review focused on signup confirmation rate. Calculate the confirmation rate as the percentage of signups that...
Stripe
Foundations Track
Top Sellers By Gross Sales
Stripe is reviewing top sellers by gross sales through a operations review. Return the top 3 sellers by total_gross_sales. Output seller_id and total_gross_s...
Wayfair
Foundations Track
Weighted Search Median
Use this Wayfair operations review to work on weighted search median. Return the weighted median number of searches from the compressed search frequency table.
Foundations Track
Customer Who Visited But Did Not Make Any Transactions
Pinterest is reviewing customer who visited but did not make any transactions through a finance summary. Return the distinct policy_holder_id values for memb...
Wayfair
Foundations Track
Employee Id And Whether The Employee Met Quota Using Values Yes Or No
Use this Wayfair scorecard to work on employee id and whether the employee met quota using values yes or no. Return each employee_id and whether the employee...
Stripe
Foundations Track
Pages With No Likes
Use this Stripe operations review to work on pages with no likes. Return every page_id that has no follower rows. Sort by page_id.
Robinhood
Foundations Track
FAANG Underperforming Stocks (part 3)
Robinhood wants a analysis pass for faang underperforming stocks (part 3). Return the distinct policy_holder_id values for members who made at least 3 calls....
Airbnb
Foundations Track
Find Total Time Spent By Each Employee
Use this Airbnb weekly brief to work on find total time spent by each employee. Return each app_id and the total number of click events recorded in 2024. Sor...
Amazon
Foundations Track
Number Of Unique Subjects Taught By Each Teacher
Amazon is reviewing number of unique subjects taught by each teacher through a diagnostic pass. Return each app_id and the total number of click events recor...
Amazon
Foundations Track
Odd And Even Transactions
Amazon wants a operations review for odd and even transactions. Return separate totals for odd-numbered and even-numbered measurement days. Return two column...
Airbnb
Foundations Track
Page Recommendation
Airbnb is reviewing page recommendation through a trend check. Return every page_id that has no follower rows. Sort by page_id.
Salesforce
Foundations Track
Patient Support Analysis (part 3)
At Salesforce, analysts are preparing a weekly brief focused on patient support analysis (part 3). Return the distinct policy_holder_id values for members wh...
Amazon
Foundations Track
Loss-Making Drug Totals
Amazon is reviewing loss-making drug totals through a scorecard. Return each manufacturer with the number of loss-making drugs and the total absolute loss. S...
TikTok
Foundations Track
Primary Department For Each Employee
At TikTok, analysts are preparing a operations review focused on primary department for each employee. Return each employee_id and whether the employee met q...
Uber
Foundations Track
Year-on-year Product Spend Growth
Use this Uber trend check to work on year-on-year product spend growth. Calculate the year-on-year growth rate for each product_id. Return report_year, produ...
Robinhood
Foundations Track
Total Traveled Distance
Robinhood is reviewing total traveled distance through a performance check. Return each app_id and the total number of click events recorded in 2024. Sort by...
Apple
Foundations Track
Heavy
At Apple, analysts are preparing a readiness review focused on heavy. Return the distinct policy_holder_id values for members who made at least 3 calls. Sort...
Tesla
Foundations Track
Quota Attainment Status
At Tesla, analysts are preparing a planning note focused on quota attainment status. Return each employee_id and whether the employee met quota as made_quota...
Robinhood
Foundations Track
Consistent Creator Activity
Robinhood wants a diagnostic pass for consistent creator activity. Return each creator_id that posted at least two items in 2024. Sort by creator_id.
Alibaba
Foundations Track
Alibaba Compressed Mode
You're given a table containing the item count for each order on Alibaba, along with the frequency of orders that have the same item count. Write a query to ...
IshaSQL
Foundations Track
DNA Pattern Recognition
Table: Samples +----------------+---------+ | Column Name | Type | +----------------+---------+ | sample_id | int | | dna_sequence | varchar | | species | va...
IshaSQL
Foundations Track
Odd and Even Transactions
Table: transactions +------------------+------+ | Column Name | Type | +------------------+------+ | transaction_id | int | | amount | int | | transaction_da...
IshaSQL
Foundations Track
Employees Whose Manager Left the Company
Table: Employees +-------------+----------+ | Column Name | Type | +-------------+----------+ | employee_id | int | | name | varchar | | manager_id | int | |...
IshaSQL
Foundations Track
Employees With Missing Information
Table: Employees +-------------+---------+ | Column Name | Type | +-------------+---------+ | employee_id | int | | name | varchar | +-------------+---------...
IshaSQL
Foundations Track
Count Salary Categories
Table: Accounts +-------------+------+ | Column Name | Type | +-------------+------+ | account_id | int | | income | int | +-------------+------+ account_id ...
IshaSQL
Foundations Track
The Latest Login in 2020
Table: Logins +----------------+----------+ | Column Name | Type | +----------------+----------+ | user_id | int | | time_stamp | datetime | +---------------...
IshaSQL
Foundations Track
Rearrange Products Table
Table: Products +-------------+---------+ | Column Name | Type | +-------------+---------+ | product_id | int | | store1 | int | | store2 | int | | store3 | ...
IshaSQL
Foundations Track
Primary Department for Each Employee
Table: Employee +---------------+---------+ | Column Name | Type | +---------------+---------+ | employee_id | int | | department_id | int | | primary_flag |...
IshaSQL
Foundations Track
Recyclable and Low Fat Products
Table: Products +-------------+---------+ | Column Name | Type | +-------------+---------+ | product_id | int | | low_fats | enum | | recyclable | enum | +--...
IshaSQL
Foundations Track
Find Total Time Spent by Each Employee
Table: Employees +-------------+------+ | Column Name | Type | +-------------+------+ | emp_id | int | | event_day | date | | in_time | int | | out_time | in...
IshaSQL
Foundations Track
The Number of Employees Which Report to Each Employee
Table: Employees +-------------+----------+ | Column Name | Type | +-------------+----------+ | employee_id | int | | name | varchar | | reports_to | int | |...
IshaSQL
Foundations Track
Find Followers Count
Table: Followers +-------------+------+ | Column Name | Type | +-------------+------+ | user_id | int | | follower_id | int | +-------------+------+ (user_id...
IshaSQL
Foundations Track
Daily Leads and Partners
Table: DailySales +-------------+---------+ | Column Name | Type | +-------------+---------+ | date_id | date | | make_name | varchar | | lead_id | int | | p...
IshaSQL
Foundations Track
Invalid Tweets
Table: Tweets +----------------+---------+ | Column Name | Type | +----------------+---------+ | tweet_id | int | | content | varchar | +----------------+---...
IshaSQL
Foundations Track
Fix Names in a Table
Table: Users +----------------+---------+ | Column Name | Type | +----------------+---------+ | user_id | int | | name | varchar | +----------------+--------...
IshaSQL
Foundations Track
Average Time of Process per Machine
Table: Activity +----------------+---------+ | Column Name | Type | +----------------+---------+ | machine_id | int | | process_id | int | | activity_type | ...
IshaSQL
Foundations Track
Patients With a Condition
Table: Patients +--------------+---------+ | Column Name | Type | +--------------+---------+ | patient_id | int | | patient_name | varchar | | conditions | v...
IshaSQL
Foundations Track
Capital Gain/Loss
Table: Stocks +---------------+---------+ | Column Name | Type | +---------------+---------+ | stock_name | varchar | | operation | enum | | operation_day | ...
IshaSQL
Foundations Track
Queries Quality and Percentage
Table: Queries +-------------+---------+ | Column Name | Type | +-------------+---------+ | query_name | varchar | | result | varchar | | position | int | | ...
IshaSQL
Foundations Track
Article Views I
Table: Views +---------------+---------+ | Column Name | Type | +---------------+---------+ | article_id | int | | author_id | int | | viewer_id | int | | vi...
IshaSQL
Foundations Track
First Login Date
Table: Activity +--------------+---------+ | Column Name | Type | +--------------+---------+ | player_id | int | | device_id | int | | event_date | date | | ...
IshaSQL
Foundations Track
Actors and Directors Who Cooperated At Least Three Times
Table: ActorDirector +-------------+---------+ | Column Name | Type | +-------------+---------+ | actor_id | int | | director_id | int | | timestamp | int | ...
IshaSQL
Foundations Track
Not Boring Movies
Table: Cinema +----------------+----------+ | Column Name | Type | +----------------+----------+ | id | int | | movie | varchar | | description | varchar | |...
IshaSQL
Foundations Track
Classes With at Least 5 Students
Table: Courses +-------------+---------+ | Column Name | Type | +-------------+---------+ | student | varchar | | class | varchar | +-------------+---------+...
IshaSQL
Foundations Track
Big Countries
Table: World +-------------+---------+ | Column Name | Type | +-------------+---------+ | name | varchar | | continent | varchar | | area | int | | populatio...
IshaSQL
Foundations Track
Customer Placing the Largest Number of Orders
Table: Orders +-----------------+----------+ | Column Name | Type | +-----------------+----------+ | order_number | int | | customer_number | int | +--------...
IshaSQL
Foundations Track
Find Customer Referee
Table: Customer +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | name | varchar | | referee_id | int | +------------...
IshaSQL
Foundations Track
Rising Temperature
Table: Weather +---------------+---------+ | Column Name | Type | +---------------+---------+ | id | int | | recordDate | date | | temperature | int | +-----...
IshaSQL
Foundations Track
Duplicate Emails
Table: Person +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | email | varchar | +-------------+---------+ id is the...
IshaSQL
Foundations Track
Employees Earning More Than Their Managers
Table: Employee +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | name | varchar | | salary | int | | managerId | int...
Airbnb
Foundations Track
3. What does the keyword DISTINCT do
The DISTINCT keyword removes duplicates from a SELECT query. Suppose you had a table of Airbnb customers, and wanted to figure out which cities the customers...
Airbnb
Foundations Track
10. What's the SQL command INTERSECT do, and when would you use it
The SQL command INTERSECT merges the results of multiple SELECT statements and keeps only those rows that are present in all sets. For example, say you were ...
Netflix
Foundations Track
2. Analyzing Ratings For Netflix Shows
Given a table of user ratings for Netflix shows, **calculate the average rating for each show within a given month.** Assume that there is a column for user ...
Oracle
Foundations Track
6. Average Sales Revenue by Product Category for Oracle
As a tech company, Oracle offers a diverse range of products including databases, cloud solutions, and other software services. The company would likely be i...
Foundations Track
10. Difference between BETWEEN and IN operators
BETWEEN is used to select rows that match a range of values, whereas the IN operator checks for values in a specified list of values. For example, to find ca...
Apple
Foundations Track
Apple Multimedia Active Users
SELECT COUNT(distinct user_id) as distinct_user_count FROM fct_multimedia_usage WHERE usage_date='2024-07-31'
Foundations Track
Google Pay Transaction Outcomes
For January 2024, what are the total counts of successful and failed transactions in each merchant category? This analysis will help the Google Pay security ...
Alibaba
Foundations Track
15 Compressed Mean
-- You're trying to find the mean number of items per order on Alibaba, rounded to 1 decimal place using tables which includes information on the count of it...
PayPal
Foundations Track
9. Filter PayPal Customer Records Based on Email Domain
As a PayPal data analyst, you are tasked with identifying user profiles that were created with corporate email addresses, specifically those that end with '@...
Walmart
Foundations Track
List of Questions + Solutions
A. Generic Questions 1. How many unique cities does the data have? SELECT DISTINCT city FROM wm_sales_data **Result Set :** city_name ----------- Yangon Nayp...
Foundations Track
9790 Number Of Processed Complaints
SELECT type, COUNT(complaint_id) FILTER(WHERE processed='TRUE') AS processed_complaints, COUNT(complaint_id) FILTER(WHERE processed='FALSE') AS non_processed...
Airbnb
Foundations Track
9629 Find The Count Of Verified And Non Verified Airbnb Hosts
SELECT host_identity_verified, COUNT(id) as n_hosts FROM airbnb_search_details GROUP BY host_identity_verified -- NOTE: very easy; shouldn't be in the Medium...
Foundations Track
9789 Find The Total Number Of Approved Friendship Requests In January And February
SELECT COUNT(*) as n_approved FROM facebook_friendship_requests WHERE date_approved BETWEEN '2019-01-01' and '2019-02-28' -- NOTE: solved on first attempt
Amazon
Foundations Track
04 Easy Amazon Purchasing Activity By Product Type
-- purchasing activity by product type -- SELECT t1.order_date, t1.product_type, ( SELECT SUM(quantity) FROM total_trans AS t2 WHERE t2.order_date <= t1.orde...
Salesforce
Foundations Track
15 Easy Salesforce Average Deal Size Part 1
--Average Deal Size-- select round(avg(num_seats * yearly_seat_cost),2) as average_deal_size from contracts
Amazon
Foundations Track
09. Average Review Ratings [Amazon Interview]
/* Given the reviews table, write a query to get the average stars for each product every month. The output should include the month in numerical value, prod...
IshaSQL
Foundations Track
Calculate Special Bonus
Table: Employees +-------------+---------+ | Column Name | Type | +-------------+---------+ | employee_id | int | | name | varchar | | salary | int | +------...
IshaSQL
Foundations Track
Percentage of Users Attended a Contest
Table: Users +-------------+---------+ | Column Name | Type | +-------------+---------+ | user_id | int | | user_name | varchar | +-------------+---------+ u...
IshaSQL
Foundations Track
Game Play Analysis I
IshaSQL is reviewing game play analysis i through a scorecard. Table: Activity +--------------+---------+ | Column Name | Type | +--------------+---------+ |...
Amazon
Foundations Track
Average Product Review Ratings
Amazon is reviewing average product review ratings through a scorecard. The product quality team wants monthly review score reporting. For each product and m...
Foundations Track
Closed Account Ratio
Use this Facebook scorecard to work on closed account ratio. The account integrity team wants the share of accounts that were closed on 2020-01-10. Return on...
Foundations Track
Cross-Region Sellers
Commerce wants to identify sellers with broad geographic reach. Return seller_id and total_gross_sales for sellers that sold in at least three distinct regio...
Amazon
Foundations Track
Category Revenue Leaders
During June 2024, each category had multiple products generating revenue. Return the highest-grossing product_id in each category along with category and tot...
Target
Foundations Track
Top Purchase per Customer
Return each user_id with the purchase_id and amount of that user’s most expensive purchase. If two purchases tie on amount, keep the earlier purchased_at row...
Microsoft
Foundations Track
Highest
Microsoft is reviewing highest through a scorecard. Return the highest-grossing product_id in each category during June 2024 along with category and total_re...
Uber
Foundations Track
Purchase Frequency Histogram
Use this Uber scorecard to work on purchase frequency histogram. Show how many users placed each number of purchases. Return purchase_count and user_count, s...
Snowflake
Foundations Track
April Webinar Share
Use this Snowflake scorecard to work on april webinar share. Return the percentage of marketing touches that were webinars in April 2024, rounded to the near...
Meta
Foundations Track
Final Account Balance
At Meta, analysts are preparing a scorecard focused on final account balance. Calculate the final balance per account_id. Credits add to the balance and debi...
Foundations Track
Employee Query Activity Histogram
At Google, analysts are preparing a scorecard focused on employee query activity histogram. Return the number of employees who issued 0 queries, 1 query, 2 q...
Meta
Foundations Track
Tax Product Filing Mix
Use this Meta scorecard to work on tax product filing mix. The total number of TurboTax filings and QuickBooks filings. Return turbotax_total and quickbooks_...
Wayfair
Foundations Track
Queue Satisfaction Averages
Wayfair wants a scorecard for queue satisfaction averages. Return queue_name and average satisfaction_score rounded to two decimals. Sort by queue_name.
Airbnb
Foundations Track
Average Annual Deal Size
Airbnb is reviewing average annual deal size through a scorecard. Return the average annual deal size across all customers rounded to two decimals.
Wayfair
Foundations Track
Average Annual Deal Size Across All Customers
Wayfair wants a operations review for average annual deal size across all customers. Return the average annual deal size across all customers rounded to two ...
Meta
Foundations Track
Laptop Vs. Mobile Viewership (2)
At Meta, analysts are preparing a operations review focused on laptop vs. mobile viewership (2). Count how many views came from laptop devices and how many c...
Foundations Track
The Number Of Employees Which Report To Each Employee
Google is reviewing the number of employees which report to each employee through a performance snapshot. Return each department_id whose average salary exce...
Foundations Track
Histogram of Tweets by Posting Frequency
Assume you're given a table Twitter tweet data, write a query to obtain a histogram of tweets posted per user in 2022. Output the tweet count per user as the...
IshaSQL
Foundations Track
Find Users with High Token Usage
Table: prompts +-------------+---------+ | Column Name | Type | +-------------+---------+ | user_id | int | | prompt | varchar | | tokens | int | +----------...
IshaSQL
Foundations Track
Find Loyal Customers
Table: customer_transactions +------------------+---------+ | Column Name | Type | +------------------+---------+ | transaction_id | int | | customer_id | in...
IshaSQL
Foundations Track
Last Person to Fit in the Bus
Table: Queue +-------------+---------+ | Column Name | Type | +-------------+---------+ | person_id | int | | person_name | varchar | | weight | int | | turn...
IshaSQL
Foundations Track
Reformat Department Table
Table: Department +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | revenue | int | | month | varchar | +------------...
IshaSQL
Foundations Track
Immediate Food Delivery II
Table: Delivery +-----------------------------+---------+ | Column Name | Type | +-----------------------------+---------+ | delivery_id | int | | customer_i...
IshaSQL
Foundations Track
Customers Who Bought All Products
Table: Customer +-------------+---------+ | Column Name | Type | +-------------+---------+ | customer_id | int | | product_key | int | +-------------+-------...
IshaSQL
Foundations Track
Swap Consecutive Students
Table: Seat +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | student | varchar | +-------------+---------+ id is the...
IshaSQL
Foundations Track
Tree Node
Table: Tree +-------------+------+ | Column Name | Type | +-------------+------+ | id | int | | p_id | int | +-------------+------+ id is the column with uni...
IshaSQL
Foundations Track
Investments in 2016
Table: Insurance +-------------+-------+ | Column Name | Type | +-------------+-------+ | pid | int | | tiv_2015 | float | | tiv_2016 | float | | lat | float...
IshaSQL
Foundations Track
Rank Scores
Table: Scores +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | score | decimal | +-------------+---------+ id is the...
Apple
Foundations Track
19 Apple Pay Volume
SELECT merchant_id, SUM(CASE WHEN LOWER(payment_method) = 'apple pay' THEN transaction_amount ELSE 0 END) AS volume FROM transactions GROUP BY 1 ORDER BY 2 D...
Foundations Track
34 Email Table Transformation
-- Each Facebook user can designate a personal email address, a business email address, and a recovery email address. -- Unfortunately, the table is currentl...
Alibaba
Foundations Track
07. Compressed Mode [Alibaba Interview]
/*Level: MEDIUM You are trying to find the most common (aka the mode) number of items bought per order on Alibaba. However, instead of doing analytics on all...
Shopify
Foundations Track
6. What is the percentage of sales for Retail vs Shopify for each month
WITH monthly_sales AS ( SELECT month_number, CASE WHEN platform = 'Retail' THEN sales ELSE 0 END AS retail_sales, CASE WHEN platform = 'Shopify' THEN sales E...
Foundations Track
01 Active User Retention
-- Assume you're given a table containing information on Facebook user actions. Write a query to obtain number of monthly active users (MAUs) in July 2022, i...
Foundations Track
2078 From Microsoft To Google
WITH employers_cte AS ( SELECT *, LEAD(employer) OVER(PARTITION BY user_id ORDER BY start_date) as next_employer FROM linkedin_users ) SELECT COUNT(DISTINCT ...
Foundations Track
9822 Average Number Of Friends
SELECT AVG(t2.num_friends) as avg_num_friends_per_user FROM ( SELECT t1.user, COUNT(friend) as num_friends FROM ( SELECT user_id as user, friend_id as friend...
Airbnb
Foundations Track
10159 Ranking Most Active Guests
SELECT id_guest, SUM(n_messages) as sum_n_messages, DENSE_RANK() OVER(ORDER BY SUM(n_messages) desc) as ranking FROM airbnb_contacts GROUP BY id_guest ORDER ...
Airbnb
Foundations Track
10161 Ranking Hosts By Beds
SELECT host_id, SUM(n_beds) as number_of_beds, DENSE_RANK() OVER(ORDER BY SUM(n_beds) desc) as rank FROM airbnb_apartments GROUP BY host_id ORDER BY number_o...
Foundations Track
9811 Find The Minimal Adwords Earnings For Each Business Type
WITH ranked_earnings as ( SELECT business_type, adwords_earnings, RANK() OVER(PARTITION BY business_type ORDER BY adwords_earnings) as rn FROM google_adwords...
Target
Foundations Track
9904 Highest Target
WITH ranked_targets as ( SELECT first_name, target, bonus, DENSE_RANK() OVER(ORDER BY target desc) as rn FROM employee ) SELECT first_name, target, bonus FRO...
Foundations Track
02 Medium Twitter Tweets Rolling Averages
-- tweets rolling average -- WITH tweet_posts AS ( SELECT user_id, tweet_date, COUNT(tweet_id) AS tweet_count FROM tweets GROUP BY user_id, tweet_date ) SELE...
Amazon
Foundations Track
05 Medium Amazon Highest Grossing Items
-- highest grossing items -- WITH top_sales AS ( SELECT category, product, SUM(spend) AS total_spend FROM product_spend WHERE DATE_PART('year', transaction_d...
Foundations Track
14 Medium Google Invalid Search Results
-- invalid search results -- WITH search_details AS ( SELECT country, SUM(num_search) AS total_search, SUM(num_search * (invalid_result_pct/100)) AS invalid_...
IshaSQL
Foundations Track
Exchange Seats
Use this IshaSQL scorecard to work on exchange seats. Table: Seat +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | s...
IshaSQL
Foundations Track
Friend Requests II: Who Has The Most Friends
IshaSQL wants a scorecard for friend requests ii: who has the most friends. Table: RequestAccepted +----------------+---------+ | Column Name | Type | +-----...
Foundations Track
Bull And Bear Word Frequency
Google is reviewing bull and bear word frequency through a scorecard. The market content team wants to count occurrences of the words bull and bear in stored...
Meta
Interview Core Track
Monthly Reactivated Users
Meta wants a scorecard for monthly reactivated users. Count how many users logged in during a month after being inactive in the previous month. Return login_...
Visa
Interview Core Track
Dormant Promo Codes
Marketing launched several promo codes in Q1 2024 and wants to retire the unused ones. Return the promo_code values for codes created between 2024-01-01 and ...
Airbnb
Interview Core Track
Waitlist Fill Rate
Marketplace ops wants to see how efficiently waitlists are being cleared. Return each city, the total number of waitlist requests, and the percentage of fulf...
PayPal
Interview Core Track
Churned Merchants with Pending Payouts
Risk ops needs a cleanup list for merchants who have already churned but still have money waiting to be disbursed. Return the merchant_id values for churned ...
CVS Health
Interview Core Track
Weekend Staffing Gaps
Regional ops wants to find stores with no staffing at all during the weekend of 2024-08-17 and 2024-08-18. Return store_id and city for stores that had zero ...
Meta
Interview Core Track
Interest Pages Without Followers
The community team wants the page_id values for interest pages that never picked up a follower. Return the page IDs in ascending order.
Interview Core Track
Most Attended Webinar Sessions
Marketing wants the three webinar sessions with the largest verified audiences. Return webinar_id, topic, and attendee_count, ordered by attendee_count desce...
Interview Core Track
Facebook Pages and Likes Analysis
Assume you're given two tables containing data about Facebook Pages and their respective likes (as in "Like a Facebook Page"). Write a query to return the ID...
IshaSQL
Interview Core Track
Bank Account Summary II
Table: Users +--------------+---------+ | Column Name | Type | +--------------+---------+ | account | int | | name | varchar | +--------------+---------+ acc...
IshaSQL
Interview Core Track
Customer Who Visited but Did Not Make Any Transactions
Table: Visits +-------------+---------+ | Column Name | Type | +-------------+---------+ | visit_id | int | | customer_id | int | +-------------+---------+ v...
IshaSQL
Interview Core Track
Top Travellers
Table: Users +---------------+---------+ | Column Name | Type | +---------------+---------+ | id | int | | name | varchar | +---------------+---------+ id is...
IshaSQL
Interview Core Track
Replace Employee ID With The Unique Identifier
Table: Employees +---------------+---------+ | Column Name | Type | +---------------+---------+ | id | int | | name | varchar | +---------------+---------+ i...
IshaSQL
Interview Core Track
List the Products Ordered in a Period
Table: Products +------------------+---------+ | Column Name | Type | +------------------+---------+ | product_id | int | | product_name | varchar | | produc...
IshaSQL
Interview Core Track
Project Employees I
Table: Project +-------------+---------+ | Column Name | Type | +-------------+---------+ | project_id | int | | employee_id | int | +-------------+---------...
IshaSQL
Interview Core Track
Sales Person
Table: SalesPerson +-----------------+---------+ | Column Name | Type | +-----------------+---------+ | sales_id | int | | name | varchar | | salary | int | ...
IshaSQL
Interview Core Track
Customers Who Never Order
Table: Customers +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | name | varchar | +-------------+---------+ id is t...
Databricks
Interview Core Track
3. How do you identify records in one table that aren't in another
To discover records in one table that are not present in another, you can utilize a LEFT JOIN and filter out any NULL values in the right-side table. For exa...
Netflix
Interview Core Track
8. Analyzing Netflix User Behavior and Content Ratings
You're a Data Analyst at Netflix, you have been asked to analyze customer behavior and their content ratings. You have the following two tables: A users tabl...
Salesforce
Interview Core Track
7. What's the difference between an inner and a full outer join
A **full outer join** returns all rows from both tables, including any unmatched rows, whereas an **inner join** only returns rows that match the join condit...
Spotify
Interview Core Track
3. What distinguishes an inner join from a full outer join
A full outer join returns all rows from both tables, including any unmatched rows, whereas an inner join only returns rows that match the join condition betw...
Tesla
Interview Core Track
11. Tesla Fleet Efficiency Analysis
You are a data analyst at Tesla and the company is focused on improving the efficiency of its vehicle fleet. Based on service data, the Company would like to...
Meta
Interview Core Track
Meta AR Filter Engagements
Which AR filters have generated user interactions in July 2024? List the filters by name.
Netflix
Interview Core Track
Netflix Country Marketing Spend
SELECT c.country_name, SUM(ms.amount_spent) as total_marketing_budget FROM fact_marketing_spend AS ms JOIN dimension_country AS c ON ms.country_id=c.country_...
Airbnb
Interview Core Track
6. Find the Average Number of Guests per Booking in Each City for Airbnb
As an analyst at Airbnb, one of the most useful insights you could provide would be to understand the average number of guests per booking across locations. ...
Oracle
Interview Core Track
10. Determine Records in One Table Not Present in Another
To find records in one table that aren't in another, you can use a LEFT JOIN and check for NULL values in the right-side table. Here is an example using two ...
Interview Core Track
4. Pinterest's Popular Boards
Pinterest users can create and share content in the form of personal "boards". Each board is categorized under a specific theme, such as "Home Decor" or "Tra...
Interview Core Track
5. Finding Records in One Table Not Present in Another
To find records in one table that aren't in another, you can use a LEFT JOIN and check for NULL values in the right-side table. Here's an example using two t...
Interview Core Track
10070 Deepmind Employment Competition
SELECT p.team_id, AVG(s.member_score) as team_score FROM google_competition_participants p JOIN google_competition_scores s ON p.member_id = s.member_id GROU...
Airbnb
Interview Core Track
10078 Find Matching Hosts And Guests In A Way That They Are Both Of The Same Gender And Nationality
SELECT distinct h.host_id, g.guest_id FROM airbnb_hosts h JOIN airbnb_guests g ON h.nationality=g.nationality and h.gender = g.gender
Interview Core Track
10088 Liked Posts
SELECT COUNT(DISTINCT p.post_id) as n_posts_with_a_like FROM facebook_posts p JOIN facebook_reactions r ON p.post_id = r.post_id and r.reaction = 'like'
Amazon
Interview Core Track
2128 Book Sales
SELECT b.book_id, COALESCE(SUM(b.unit_price*od.quantity), 0) as total_sales FROM amazon_books b LEFT JOIN amazon_books_order_details od ON b.book_id=od.book_...
Robinhood
Interview Core Track
01 Easy Robinhood Cities With Completed Trades
-- clients with completed trades -- SELECT u.city, COUNT(t.order_id) AS total_orders FROM trades AS t INNER JOIN users AS u ON t.user_id = u.user_id WHERE t....
IshaSQL
Interview Core Track
Sales Analysis III
Table: Product +--------------+---------+ | Column Name | Type | +--------------+---------+ | product_id | int | | product_name | varchar | | unit_price | in...
Interview Core Track
Average Employee Popularity By Location
Facebook wants a scorecard for average employee popularity by location. The workplace insights team wants to compare employee survey popularity by office loc...
Interview Core Track
Posts With Heart Reactions
At Facebook, analysts are preparing a scorecard focused on posts with heart reactions. The engagement team wants the full post records for posts that receive...
TikTok
Analytics Reporting Track
Seven-Day Trial Conversion
The growth team wants to compare acquisition channels for January trial signups. For each acquisition_channel, return the number of users who converted withi...
Stripe
Interview Core Track
Average Minutes to First Reply
Support leadership wants to compare response speed across inboxes. For conversations created in May 2024, return each inbox_name and the average number of mi...
Amazon
Interview Core Track
Store Refund Share
Retail finance wants to compare refund pressure by store for April 2024 orders. Return store_id, total_sales, refunded_amount, and refund_pct rounded to two ...
Wayfair
Analytics Reporting Track
Carrier Late Shipment Rate
Operations wants to compare carrier reliability for June 2024 shipments. Return each carrier_name, total_shipments, and the late_shipment_pct rounded to two ...
CVS Health
Analytics Reporting Track
Vendor Delivery Gaps
The supply team wants to review long breaks between deliveries. For each vendor_id, return rows where the gap between one delivery and the previous delivery ...
PayPal
Analytics Reporting Track
First Purchase Revenue by Signup Month
Revenue planning wants to understand how much first-time purchase revenue is coming from each merchant signup cohort. Return signup_month and the total value...
Meta
Analytics Reporting Track
Severity-One Resolution Pace
Reliability engineering wants to compare how quickly teams resolve the most urgent incidents. Return team_name, critical_incidents, and avg_resolution_hours ...
Robinhood
Analytics Reporting Track
Backlog Older Than Three Days
Operations wants to compare teams based on how often tickets stay unresolved for more than three days. Return team_name, total_tickets, aged_tickets, and age...
Netflix
Analytics Reporting Track
Quarterly Headcount Change
People analytics wants the most recent quarter-over-quarter headcount change for each team. Return team_name, current_headcount, prior_headcount, and headcou...
Interview Core Track
Remaining Server Capacity
Each server has a total capacity and may have multiple workloads assigned. Return server_id and remaining_capacity for every server, including servers with n...
Etsy
Analytics Reporting Track
Same-Week Repeat Buyers
Count the number of users who placed at least two orders in the same calendar week. Return a single value named repeat_buyers.
Databricks
Analytics Reporting Track
Second Customer Transaction
At Databricks, analysts are preparing a scorecard focused on second customer transaction. Return each user_id and transaction_date for the second transaction...
Interview Core Track
Final Account Balances
Use this Pinterest operations review to work on final account balances. Calculate the final balance per account_id. Credits add to the balance and debits sub...
Meta
Analytics Reporting Track
Rapid Repeat Payment Alerts
Meta is reviewing rapid repeat payment alerts through a scorecard. Count how many repeated payments happened within 10 minutes for the same merchant_id, cred...
Interview Core Track
Unique Money Transfer Relationships
Use this Pinterest operations review to work on unique money transfer relationships. Count unique transfer relationships regardless of direction. Return rela...
Meta
Analytics Reporting Track
May Orders By Region
Use this Meta scorecard to work on may orders by region. Return each region and the number of orders placed during May 2024. Sort by region.
Airbnb
Analytics Reporting Track
April Weekly Event Totals
Airbnb wants a scorecard for april weekly event totals. Return the week_start date and total_events for April 2024. Sort by week_start.
Analytics Reporting Track
Unique Orders And Customers Per Month
Use this Pinterest performance snapshot to work on unique orders and customers per month. Return each region and the number of orders placed during May 2024....
IshaSQL
Interview Core Track
Find COVID Recovery Patients
Table: patients +-------------+---------+ | Column Name | Type | +-------------+---------+ | patient_id | int | | patient_name| varchar | | age | int | +----...
IshaSQL
Interview Core Track
Find Product Recommendation Pairs
Table: ProductPurchases +-------------+------+ | Column Name | Type | +-------------+------+ | user_id | int | | product_id | int | | quantity | int | +-----...
IshaSQL
Interview Core Track
Analyze Subscription Conversion
Table: UserActivity +------------------+---------+ | Column Name | Type | +------------------+---------+ | user_id | int | | activity_date | date | | activit...
IshaSQL
Interview Core Track
Confirmation Rate
Table: Signups +----------------+----------+ | Column Name | Type | +----------------+----------+ | user_id | int | | time_stamp | datetime | +--------------...
IshaSQL
Interview Core Track
Movie Rating
Table: Movies +---------------+---------+ | Column Name | Type | +---------------+---------+ | movie_id | int | | title | varchar | +---------------+--------...
IshaSQL
Interview Core Track
Students and Examinations
Table: Students +---------------+---------+ | Column Name | Type | +---------------+---------+ | student_id | int | | student_name | varchar | +-------------...
IshaSQL
Interview Core Track
Average Selling Price
Table: Prices +---------------+---------+ | Column Name | Type | +---------------+---------+ | product_id | int | | start_date | date | | end_date | date | |...
IshaSQL
Interview Core Track
2019 Buyer Orders
Table: Users +----------------+---------+ | Column Name | Type | +----------------+---------+ | user_id | int | | join_date | date | | favorite_brand | varch...
IshaSQL
Interview Core Track
Next Day Login Fraction
Table: Activity +--------------+---------+ | Column Name | Type | +--------------+---------+ | player_id | int | | device_id | int | | event_date | date | | ...
IshaSQL
Interview Core Track
Product Sales Analysis III
Table: Sales +-------------+-------+ | Column Name | Type | +-------------+-------+ | sale_id | int | | product_id | int | | year | int | | quantity | int | ...
IshaSQL
Interview Core Track
Department Highest Salary
Table: Employee +--------------+---------+ | Column Name | Type | +--------------+---------+ | id | int | | name | varchar | | salary | int | | departmentId ...
Target
Interview Core Track
Source Target ID Reconciliation
Given two tables source and target, identify the following: IDs present in the source table but not in the target table. IDs present in the target table but ...
Snapchat
Interview Core Track
02 Sending Vs Opening Snaps
-- Assume you're given tables with information on Snapchat users, including their ages and time spent sending and opening snaps. -- Write a query to obtain a...
Microsoft
Interview Core Track
10 Supercloud Customer
-- A Microsoft Azure Supercloud customer is defined as a company that purchases at least one product from each product category. -- Write a query that effect...
Interview Core Track
4. Determine the Most Popular Google Search Category
For this scenario, assume that Google wants to analyze the top searched categories in their platform to optimize their search results. We have two tables, se...
Oracle
Interview Core Track
2. Designing Database for Oracle's Employee Training Program
Oracle is starting a new Employee Training Program and wants to keep track of each employee's progress. The program includes multiple courses, and each cours...
Spotify
Interview Core Track
1. Identify Spotify's Most Frequent Listeners
Spotify wants to identify their 'whale users', these are users who listen to the most tracks every month. They are potential customers to involve in user fee...
Spotify
Interview Core Track
8. Calculate the average listening duration for each music genre on Spotify
Suppose that Spotify would like to understand better the average listening duration for each genre of music on their platform. **Write a SQL query that calcu...
Uber
Interview Core Track
7. Could you describe a self-join and provide a scenario in which it would be used
A self-join is a type of join in which a table is joined to itself. To perform a self-join, you need to specify the table name twice in the FROM clause, and ...
Airbnb
Interview Core Track
11. Analyze Host Listings and Booking Transactions
As an Airbnb data analyst, you have been asked to analyze the performance of hosts' listings in the past year. Your task is to **identify the top 10 listings...
Databricks
Interview Core Track
1. Identifying Power Users for Databricks
As a Databricks data analyst, one of the most important tasks is identifying our power users. These are users who frequently use Databricks' tools and servic...
Airbnb
Interview Core Track
10074 Find The Average Age Of Guests Reviewed By Each Host
SELECT from_user, AVG(age) as average_age FROM airbnb_reviews r JOIN airbnb_guests g ON r.to_user = g.guest_id WHERE from_type = 'host' GROUP BY from_user
Interview Core Track
2081 Recommendation System
-- Problem Statement: -- You are given the list of Facebook friends and the list of Facebook pages that users follow. Your task is to create a new recommenda...
Interview Core Track
9777 Successfully Sent Messages
WITH success_or_not as ( SELECT ms.message_id, CASE WHEN mr.message_id IS NOT NULL THEN 1 ELSE 0 END as receive_success FROM facebook_messages_sent ms LEFT J...
IshaSQL
Interview Core Track
Market Analysis I
IshaSQL wants a scorecard for market analysis i. Table: Users +----------------+---------+ | Column Name | Type | +----------------+---------+ | user_id | in...
IshaSQL
Interview Core Track
Game Play Analysis IV
At IshaSQL, analysts are preparing a scorecard focused on game play analysis iv. Table: Activity +--------------+---------+ | Column Name | Type | +---------...
TikTok
Analytics Reporting Track
One-Month Creator Retention
Growth wants a basic cohort view for creator retention. For signup_month values from 2024-01-01 through 2024-03-01, return the cohort size, the number of cre...
Etsy
Analytics Reporting Track
Revenue Rank Within Category
Merchandising wants the top products by revenue inside each category. Return the top two products per category with category, product_name, total_revenue, an...
Uber
Analytics Reporting Track
Consecutive Delay Streaks
Dispatch wants the longest streak of delayed service days for each driver. Return driver_id and longest_streak, where a streak counts consecutive trip_date v...
Analytics Reporting Track
Power Usage Outliers
Infrastructure wants to flag racks with unusual power spikes. Return rack_id, usage_date, kilowatt_hours, and the rack_average rounded to two decimals for ro...
Shopify
Analytics Reporting Track
Rising Basket Buyers
The retention team wants to identify buyers whose first three orders show steadily larger baskets. Return buyer_id values where the first order total is less...
Shopify
Interview Core Track
Running Spend by Product Line
For each product_line, return the cumulative revenue by order_date. Output order_date, product_line, and cumulative_revenue. Sort by product_line and order_d...
Fitbit
Interview Core Track
Daily Alternating Measurement Totals
Operations needs a daily split between alternating sensor readings. For each day, order measurements by measured_at, add the 1st, 3rd, 5th, and later odd-pos...
Stripe
Interview Core Track
Rapid Repeat Card Payments
Risk operations wants to flag merchants that received back-to-back payments for the same amount within a ten-minute window. For each merchant_id, return repe...
Alibaba
Interview Core Track
Rolling Three-day Earnings
At Alibaba, analysts are preparing a scorecard focused on rolling three-day earnings. Return each user_id, transaction_date, and rolling_3_day_earnings based...
Interview Core Track
Rolling Three
Use this LinkedIn operations review to work on rolling three. Return each user_id, transaction_date, and rolling_3_day_earnings based on the current day plus...
Spotify
Interview Core Track
Linkedin Power Creators (part 1)
Spotify wants a scorecard for linkedin power creators (part 1). Return each pair of products that were purchased together in the same order. Output product_i...
Databricks
Interview Core Track
Customers Buying Every Category
Databricks wants a scorecard for customers buying every category. Return each customer_id that purchased at least one product in every product_category. Sort...
Wayfair
Interview Core Track
Products Purchased Together
Use this Wayfair operations review to work on products purchased together. Return each pair of products that were purchased together in the same order. Outpu...
Spotify
Interview Core Track
Products Bought Together
Spotify is reviewing products bought together through a trend check. Return each pair of products that were purchased together in the same order. Output prod...
IshaSQL
Interview Core Track
Find Emotionally Consistent Users
Table: reactions +--------------+---------+ | Column Name | Type | +--------------+---------+ | user_id | int | | content_id | int | | reaction | varchar | +...
IshaSQL
Interview Core Track
Most Common Course Pairs
Table: course_completions +-------------------+---------+ | Column Name | Type | +-------------------+---------+ | user_id | int | | course_id | int | | cour...
IshaSQL
Interview Core Track
Find Books with Polarized Opinions
Table: books +-------------+---------+ | Column Name | Type | +-------------+---------+ | book_id | int | | title | varchar | | author | varchar | | genre | ...
IshaSQL
Interview Core Track
Find Consistently Improving Employees
Table: employees +-------------+---------+ | Column Name | Type | +-------------+---------+ | employee_id | int | | name | varchar | +-------------+---------...
IshaSQL
Interview Core Track
Seasonal Sales Analysis
Table: sales +---------------+---------+ | Column Name | Type | +---------------+---------+ | sale_id | int | | product_id | int | | sale_date | date | | qua...
IshaSQL
Interview Core Track
Restaurant Growth
Table: Customer +---------------+---------+ | Column Name | Type | +---------------+---------+ | customer_id | int | | name | varchar | | visited_on | date |...
IshaSQL
Interview Core Track
Human Traffic of Stadium
Table: Stadium +---------------+---------+ | Column Name | Type | +---------------+---------+ | id | int | | visit_date | date | | people | int | +----------...
IshaSQL
Interview Core Track
Trips and Users
Table: Trips +-------------+----------+ | Column Name | Type | +-------------+----------+ | id | int | | client_id | int | | driver_id | int | | city_id | in...
IshaSQL
Interview Core Track
Department Top Three Salaries
Table: Employee +--------------+---------+ | Column Name | Type | +--------------+---------+ | id | int | | name | varchar | | salary | int | | departmentId ...
Walmart
Interview Core Track
12 Histogram Of Users And Purchases
-- Assume you're given a table on Walmart user transactions. Based on their most recent transaction date, write a query that retrieve the users along with th...
Apple
Interview Core Track
9. Follow-Up AirPod Percentage
The Apple Customer Retention Data Science team needs your help to investigate buying patterns related to AirPods and iPhones. Write a SQL query to determine ...
Interview Core Track
11 Odd And Even Measurements
-- Assume you're given a table with measurement values obtained from a Google sensor over multiple days with measurements taken multiple times within each da...
Interview Core Track
9793 Average Time Between Steps
WITH step_differences AS ( SELECT feature_id, user_id, step_reached, timestamp, LEAD(timestamp) OVER (PARTITION BY feature_id, user_id ORDER BY step_reached)...
IshaSQL
Interview Core Track
Find Stores with Inventory Imbalance
Table: stores +-------------+---------+ | Column Name | Type | +-------------+---------+ | store_id | int | | store_name | varchar | | location | varchar | +...
Interview Core Track
Linkedin Power Creators
At LinkedIn, analysts are preparing a scorecard focused on linkedin power creators. The creator analytics team wants to identify personal profiles that have ...
Interview Core Track
Handyman Earnings Per Employee Mode
Use this Google scorecard to work on handyman earnings per employee mode. The ads finance team wants the most common adwords earnings per employee value amon...
Interview Core Track
Top Department Salaries
Twitter wants a scorecard for top department salaries. The compensation team wants the top salary levels in each department. Rank salaries within each depart...