SQL for Average Process Time | Dataford Interview Questions

Write a SQL query to find the average time taken for each operational process in a given dataset.

Use the provided process and execution data. Calculate elapsed time only for completed executions with valid timestamps, while retaining processes with no qualifying executions.

Output

One row per operational process with process_id, process_name, and average_duration_seconds.
Return NULL when a process has no qualifying executions.
Order by process_id ascending.

Schema

operational_processes

Column	Type	Description
process_idPK	INT	Unique identifier for the operational process
process_name	VARCHAR(100)	Name of the operational process

process_executions

Column	Type	Description
execution_idPK	INT	Unique identifier for an execution
process_id	INT	Process associated with the execution
status	VARCHAR(20)	Execution status
started_at	TIMESTAMP	Execution start timestamp
completed_at	TIMESTAMP	Execution completion timestamp

Your question is SQL for Average Process Time. Start with the requirements and the two tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem