Python Backend Performance Bottlenecks | Dataford Interview Questions

What are the common performance bottlenecks you have encountered in Python-based backend systems?

For this SQL exercise, analyze backend request logs and identify endpoints that show consistently high response times. Include only endpoints with at least two requests and an average duration of at least 300 milliseconds.

Output

One row per qualifying endpoint with endpoint_name, request_count, average_duration_ms, error_count, and error_rate_pct.
Sort by average duration descending, then endpoint name ascending for ties.

Schema

endpoints

Column	Type	Description
endpoint_idPK	INT	Unique endpoint identifier
endpoint_name	VARCHAR(100)	Readable endpoint name
method	VARCHAR(10)	HTTP method
path	VARCHAR(200)	HTTP route path

request_logs

Column	Type	Description
log_idPK	INT	Unique request log identifier
endpoint_id	INT	Referenced endpoint identifier
requested_at	TIMESTAMP	Request timestamp
duration_ms	INT	Request duration in milliseconds
status_code	INT	HTTP response status code

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Problem