When two or more separate queries need to be combined into a single dataset, Interactive Reporting provides an interface for combining queries using the Union, Union All, Intersection, and Minus operators. In SQL, these specific operators are specified between two queries driving the behavior of interest. Each operator is defined as follows:
The Union operator combines distinct records between both queries. If the same record exists in both queries, the record is only returned once from the database.
The Union All operator combines all the records between both queries.
The Intersection operator returns the rows that match between both queries. If the same record appears in both queries, the record is returned. If the record does not match, it is excluded from the query results.
The Minus operator returns all of the records from the first query that does not have a match in the second query.