![]() You can join it to its source imported dataset.Self JoinĪ self join is a join operation between a dataset and a copy of itself. For example, you can use a self-join to invert the structure of hierarchical data, such as brand-product or manager-employee.ĭataprep by Trifacta supports joins between a recipe and any upstream recipe or dataset. NOTE: Depending on the size of your datasets, a cross join can greatly expand the size of the output, which may increase costs in some environments. Each row in the right table appears in the results, regardless of whether there are matches in the left table.įor the preceding example tables, a right join on the DepartmentID table produces the following result table: A right join does not require that there be matching records for each value in the key value of the secondary (right) table. However, since there are no corresponding values in the Department table, the corresponding fields in the result table are NULL values.Ī right join (or right outer join) is the reverse of a left join. In this left join, the Mary Martin row has been added to the result, since her record in the Employee table does contain an entry for the DepartmentID.
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