Jointype
Jointype is a term used in relational databases and query processing to describe the category of a join operation that combines two data sources based on a join condition. It defines how rows from the input sources are matched, what criteria are used, and what rows appear in the result.
Common jointypes include inner join, left outer join, right outer join, full outer join, and cross join.
In SQL and other query languages, the jointype is specified or implied by join syntax (for example,