Advanced Window Functions

MediumSQL · PostgreSQL00:00

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Your question is Advanced Window Functions. Start with the requirements and the three tables on the right.

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Problem

Write a SQL query using advanced window functions such as DENSE_RANK and RANK(). Asked in the Technical Round 2 stage. This was the first SQL question of round 2.

Use the provided employee, department, and assessment score data. Include active employees assigned to a department, treating missing completed scores as zero.

Output

One row per included employee with department_name, employee_name, total_points, dense_rank, and rank.
Rank employees within each department by total points descending. Tied employees share both ranks.
Order by department_name, rank, then employee_id.

Schema

departments

Column	Type	Description
department_idPK	INT	Unique department identifier
department_name	VARCHAR(100)	Department name

employees

Column	Type	Description
employee_idPK	INT	Unique employee identifier
employee_name	VARCHAR(100)	Employee name
department_id	INT	Assigned department identifier
is_active	BOOLEAN	Whether the employee is active

assessment_scores

Column	Type	Description
score_idPK	INT	Unique assessment score identifier
employee_id	INT	Employee receiving the score
points	INT	Points earned for the assessment
completed	BOOLEAN	Whether the assessment was completed

Tablesemployeesdepartmentsassessment_scores

Your solutionPostgreSQL

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