The Join processor allows you to apply four different types of join operations to your hierarchical data.
Inner join
This type of join operation is used to:
- match the values that are common between two datasets.
- create a result set with all the pairs that match.
The result set is determined as follows:
| If the join statement is satisfied (dataset L matches dataset R) | If the join statement is not satisfied |
|---|---|
| All matching records are combined and returned in the result set | Non-matching records are ignored |
Left outer join
This type of join operation is used to:
- match the values that are common between two datasets AND retain all the values that exists in the left dataset
- create a result set combining these records
The result set is determined as follows:
| If the join statement is satisfied (everything that is in dataset L + matches in the two datasets) | If the join statement is not satisfied |
|---|---|
| All records in the left dataset as well as the matching records between dataset left and dataset right are combined and returned in the result set | Non-matching records are ignored |
Right outer join
This type of join operation is used to:
- match the values that are common between two datasets AND retain all the values that exists in the right dataset.
- create a result set combining these records.
The result set is determined as follows:
| If the join statement is satisfied (everything that is in dataset L and R + matches in the two datasets) | If the join statement is not satisfied |
|---|---|
| All records in the left dataset as well as the matching records between dataset left and dataset right are combined and returned in the result set | Non-matching records are ignored |
Full outer join
This type of join operation is used to:
- retain all the values that match in the left and right datasets.
- create a result set combining these records.
The result set is determined as follows:
| If the join statement is satisfied (everything that is in dataset L + matches in the two datasets) | If the join statement is not satisfied |
|---|---|
| All records in the left dataset as well as the matching records between dataset left and dataset right are combined and returned in the result set | Non-matching records will be listed in the result set as NULL |