JOIN visualizer
People are the left table. Tasks are the right table. Sophie has no task. One task has no person. Change the join type and the keys to see who remains.
people
| id | name |
|---|---|
| 1 | Maya |
| 2 | Andre |
| 3 | Sophie |
tasks
| id | person_id | title |
|---|---|---|
| 10 | 1 | Design the metric |
| 11 | 1 | Review the query |
| 12 | 2 | Load the warehouse |
| 13 | NULL | Unassigned cleanup |
INNER JOIN keeps only pairs whose keys match. Sophie and the unassigned task disappear.
INNER JOIN result
| person | task |
|---|---|
| Maya | Design the metric |
| Maya | Review the query |
| Andre | Load the warehouse |