Headcount by Department

EasySQLSQL

Solve this the way you would in the interview: out loud, on a timer, with an AI interviewer asking follow-ups while you code. You get a scored report at the end.

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Problem

Table departments: id INTEGER primary key name TEXT Table employees: id INTEGER primary key name TEXT department_id INTEGER may be NULL for someone not yet assigned Return every department with the number of employees in it. A department with nobody in it must still appear, with 0. Columns, in this order: department name, headcount. Order by headcount descending, then department name ascending.

Examples

Input: departments employees id | name id | name | department_id 1 | Design 1 | Ana | 2 2 | Engineering 2 | Ben | 2 3 | Cho | NULL
Output: Engineering | 2 Design | 0

Constraints

  • Unassigned employees are not counted anywhere.

What the interviewer grades

A correct solution is one of five scores. The report also grades problem understanding (did you clarify inputs and edge cases before coding), problem solving, communication while you work, code quality, and testing. See a sample report, or read up on the pattern in the lessons.

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