Business Context
Diligent Robotics operations leaders need a weekly view of how sites using Moxi are performing. The report should show completed task volume and turnaround trends while preserving sites and robots that may have no completed work.
Task
Write a PostgreSQL query that analyzes completed tasks by site and Monday-based calendar week. Use started_at to determine the week and calculate turnaround from started_at to completed_at.
Requirements
- Include only tasks with
status = 'completed' and non-null timestamps.
- Return site name, week start, completed task count, and average turnaround in minutes rounded to two decimals.
- Use
LAG to calculate week-over-week percentage change for both completed task count and average turnaround, comparing each site with its previous reported week.
- Return sites in chronological order, with each site's weeks ordered ascending. Return null percentage changes when no prior week exists or the prior value is zero.
