What are some good examples where SQL's OUTER JOIN is used?

sql join left-join outer-join
nonopolarity picture nonopolarity · Apr 23, 2010 · Viewed 26.5k times · Source

I often get asked the questions in an interview that "what is an outer join in SQL"?

While it can be answered, I wonder what might be some classic and good real life examples where a (LEFT) OUTER JOIN is used?

Answer

Raj Kaimal picture Raj Kaimal · Apr 23, 2010

In the Northwind database on the Customers and Orders table.

Doing an inner join will only give you customers that have placed orders.

Doing an outer join will get all customers and orders for customers that have placed orders.

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