SQL Join With Aggregated Counts

EasySQL · PostgreSQL00:00

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Your question is SQL Join With Aggregated Counts. Start with the requirements and the two tables on the right.

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Problem

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

Tablesmodel_categoriesinference_runs

Your solutionPostgreSQL

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