Paypal Data Scientist Data Manipulation (SQL/Python) Interview Questions
Master your tech interview with our curated database of real questions from top companies.
Clean and Analyze User Transactions with Python Functions
transactions +---------+---------------------+---------+ | user_id | trans_ts | amount | +---------+---------------------+---------+ | 11 ...
Identify Users with Specific Page Visit Sequence
page_visits +------------+---------+---------+----------+ | date | user_id | page_id | ts | +------------+---------+---------+----------+ ...
Identify Session with Maximum Overlapping Sessions Count
sessions | session_id | start_time | end_time | | 1 | 2023-01-01 09:00:00 | 2023-01-01 10:00:00 | | 2 | 2023-0...
Analyze Transactions and Classify by Amount in SQL
transactions +---------------+---------+--------+---------+---------------------+-----------------+ | transaction_id| user_id | amount | status | ts ...
Write SQL to flag Venmo ATO
SQL case: You are a Decision Scientist on Venmo’s Fraud (ATO) team. Using the schema and sample data below, write a single Standard SQL query that ret...
Write conditional aggregation SQL queries
Question Write an SQL query to compute the total amount for rows satisfying a condition, comparing approaches that use SUM(CASE WHEN … THEN … END) ver...
Calculate and Find Average Contacts and Sync Percentage
dw_peers +--------------+---------------+-------------+ | user_id | synced_contact| date_synced | +--------------+---------------+-------------+ ...
Explain Window Functions and Joins in SQL and Python
TABLE transactions | transaction_id | user_id | merchant | amount | currency | transaction_ts | | 1001 | 17 | Walmart | 45.80...
Clean and Summarize User Purchase Data Efficiently
transactions +-----------+---------------------+-----------+--------+ | user_id | txn_timestamp | txn_value | txn_id | +-----------+----------...
Identify Users with Specific Page Navigation Patterns
page_visits +------------+---------+---------+---------------------+ | visit_date | user_id | page_id | ts | +------------+---------+...
Write conditional aggregates with CASE WHEN
Write a query that produces conditional aggregates using CASE WHEN (e.g., counts of approved vs declined transactions per merchant and the sum of amou...
Compare WHERE vs HAVING with aggregates
Filter groups based on an aggregate and explain WHERE vs HAVING. Provide a query that returns merchants with chargeback_rate > 0.5% in the last 30 day...