7-Day Rolling Network Traffic

Juniper Networks uses daily telemetry from Juniper Mist and Junos devices to monitor network demand. Write a PostgreSQL query that calculates a seven-day rolling average of daily traffic and compares it with the immediately preceding seven-day period.

Requirements

1. Aggregate traffic by calendar date, treating missing dates and NULL traffic values as zero.
2. Generate a contiguous daily time series so each rolling window represents seven calendar days.
3. Calculate the current seven-day average, the previous seven-day average, the absolute change, and the percentage change.
4. Return only dates with two complete, non-overlapping seven-day periods, ordered chronologically.