A unique join is a type of join that eliminates duplicate rows from the result set. It is not available in the Information Designer, as it is not a standard SQL join operator. The join operators that are available in the Information Designer are: inner join, left outer join, right outer join, full outer join, left single match join, right single match join, and freehand join12. These join operators can be used to define how rows in different tables relate to one another, and can be reused in multiple information links3. References: Creating a Join in Information Designer, Freehand Joins in Information Designer, Overview of Joins in Information Designer