SQL Join With Aggregated Counts | Dataford Interview Questions

The Fractal AI platform tracks model inference runs across multiple analytical categories. Write a PostgreSQL query that reports how many completed inference runs belong to each matching model category.

Requirements

Join inference_runs to model_categories using category_id and return only rows with a matching category.
Count completed runs for each category, excluding runs with other statuses.
Return categories ordered by completed run count descending, then category name ascending for ties.

Schema

model_categories

Column	Type	Description
category_idPK	INT	Unique model category identifier
category_name	VARCHAR(50)	Name of the analytical category

inference_runs

Column	Type	Description
run_idPK	INT	Unique inference run identifier
category_id	INT	Category associated with the inference run
run_status	VARCHAR(20)	Current status of the inference run

Your question is SQL Join With Aggregated Counts. 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