Unfinished Assembly Lines

SQLEasyJunior levelTesla~15 min

Problem

**[Asked at Tesla]**

Tesla's production team tracks every assembly step for each vehicle part.
A part moves through several steps; each step has a start time but only gets
a finish time when it completes successfully.

Find all part–step combinations that have been **started but not yet finished**
(i.e., `finish_date` is NULL). These are the current bottlenecks on the line.
Sort results by part name, then step number.

Tables

Example rows — the live problem includes the full dataset.

assembly_log

log_id	part	assembly_step	start_date	finish_date

Expected output

Your answer should return 4 rows with the columns part, assembly_step.

Starter code (SQL)

SELECT *
FROM assembly_log;

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