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Employee and Department Join With NULLs

EasySQL · PostgreSQL00:00
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Your question is Employee and Department Join With NULLs. Start with the requirements and the two tables on the right.

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Problem

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

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

Schema

employees
ColumnTypeDescription
emp_idPKINTUnique employee identifier
nameVARCHAR(100)Employee full name
dept_idINTOptional reference to departments.dept_id
departments
ColumnTypeDescription
dept_idPKINTUnique department identifier
dept_nameVARCHAR(100)Department display name
Tablesemployeesdepartments
Your solutionPostgreSQL
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