Analyze Recent User Engagement in Video Calls

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Q: What difficulty level is this coding question?

This is a Medium difficulty Data Manipulation (SQL/Python) question, commonly asked during Technical Screen rounds at Meta.

Q: What role is this question designed for?

This question is commonly asked for Data Scientist candidates at Meta during technical interviews.

Question

calls

+-----------+-----------+---------------------+---------+---------+
| caller_id | callee_id | call_start_timestamp| country | call_id |
+-----------+-----------+---------------------+---------+---------+
| 1         | 2         | 2023-03-10 14:05:00 | France  | 101     |
| 1         | 3         | 2023-03-12 09:20:00 | France  | 102     |
| 1         | 4         | 2023-03-13 18:40:00 | France  | 103     |
| 2         | 5         | 2023-03-13 12:10:00 | Germany | 104     |
| 3         | 1         | 2023-03-14 07:55:00 | France  | 105     |

##### Scenario

Video-call product analytics team wants quick health checks on recent engagement.

##### Question

How many users started a call with more than three different people in the last seven days?

What percentage of yesterday’s DAUs located in France were on at least one video call?

##### Hints

Think window functions, DISTINCT callee counts, filtering by DATE(call_start_timestamp).

PracHub · Accepted Answer

This question evaluates competency in data manipulation and product analytics, focusing on transforming event-level call records into user-level engagement metrics using SQL or Python; the category is Data Manipulation (SQL/Python).

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