Definition - What does Outer Join mean?
An outer join in SQL is a specific kind of query construction that deliberately allows for a wider array of results. The process of building specific queries in SQL to get database results is a highly technical one, and an outer join is an example of a type of detail learned and utilized by database researchers.
Techopedia explains Outer Join
Someone who is writing a query can use a left or right outer join to include table results that only have a given component, rather than requiring multiple components to be present. A left outer join includes all rows in a table regardless of whether a specifically positioned column has results or not. By contrast, an inner join requires both components to be present.
Because outer joins provide for more diversity, they are often useful in searches that are less rigid and do not require strict adherence to the principle of having consistent data from multiple search components.