Odd and Even Sensor Readings

SQLMediumMid levelGoogle~15 min

Problem

**[Asked at Google]**

Industrial sensors emit readings throughout the day. For each calendar day,
readings are numbered in time order: 1st, 2nd, 3rd, … The data team wants:
- Sum of readings at **odd positions** (1st, 3rd, 5th, …)
- Sum of readings at **even positions** (2nd, 4th, 6th, …)

Return `reading_day`, `odd_sum`, `even_sum`, ordered by reading_day.

Tables

Example rows — the live problem includes the full dataset.

sensor_readings

reading_id	value	recorded_at

Expected output

Your answer should return 2 rows with the columns reading_day, odd_sum, even_sum.

Starter code (SQL)

SELECT *
FROM sensor_readings;

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