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Below is an example of a right outer join (the OUTER keyword is optional), with the additional result row italicized: SELECT * FROM employee RIGHT OUTER JOIN department ON employee . DepartmentID = department .
The right outer join of relations R and S is written as R S. [e] The result of the right outer join is the set of all combinations of tuples in R and S that are equal on their common attribute names, in addition to tuples in S that have no matching tuples in R. [citation needed] For example, consider the tables Employee and Dept and their right ...
The join operation defined for relational databases is often referred to as a natural join (⋈). In this type of join, two relations are connected by their common attributes. MySQL's approximation of a natural join is the Inner join operator. In SQL, an INNER JOIN prevents a cartesian product from occurring when there are two tables in a query.
For example, one variant of the block nested loop join reads an entire page of tuples into memory and loads them into a hash table. It then scans S {\displaystyle S} , and probes the hash table to find S {\displaystyle S} tuples that match any of the tuples in the current page of R {\displaystyle R} .
A right join is employed over the Target (the INTO table) and the Source (the USING table / view / sub-query)--where Target is the left table and Source is the right one. The four possible combinations yield these rules:
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The current text for right outer join states that they're rarely used because they can be replaced by left outer joins, but it doesn't provide any examples of why they might ever be used. One situation I have occasionally found use for them is when I have a single table needing to be left outer joined to two inner joined tables.
One day after special counsel Jack Smith moved to dismiss both his cases against President-elect Donald Trump, the U.S. Court of Appeals for the Eleventh Circuit complied by dropping Trump from ...