LEFT OUTER JOIN


### left outer join 성능 구림
### left outer == left
![](https://www.notion.so/image/https%3A%2F%2Fs3-us-west-2.amazonaws.com%2Fsecure.notion-static.com%2F8ed519a5-6972-4d00-b98f-a861f3296e2e%2FUntitled.png?table=block&id=b285baa4-c12e-47e1-95c3-0d52876197a4&cache=v2)

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