Employee and Department Join With NULLs | Dataford Interview Questions

Yardi Voyager exports employee records separately from department reference data. Write a PostgreSQL query that reports each employee and the department name associated with their dept_id.

Requirements

Return every employee, including employees whose dept_id is NULL.
Match employees to departments using dept_id.
Return emp_id, name, and dept_name.
Sort the result by emp_id in ascending order. If no department matches, dept_name must remain NULL.

Schema

employees

Column	Type	Description
emp_idPK	INT	Unique employee identifier
name	VARCHAR(100)	Employee full name
dept_id	INT	Optional reference to departments.dept_id

departments

Column	Type	Description
dept_idPK	INT	Unique department identifier
dept_name	VARCHAR(100)	Department display name

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