Modeling Guide

Join

A Join node represents a relational multiway join operation.

Context

The Join node can perform multiple step joins on two or more inputs.

Procedure

  1. (Optional) On the Columns tab, click the + icon to include columns that may not be mapped from the source.
  2. (Optional) Remove any output columns by clicking the x icon. The Output column shows how the column has been mapped with the input source. You can change the column, if necessary.
  3. Click the Criteria tab and use the Table Editor to define the Left join partner, the Join Type.
  4. Click the + icon to choose the join Partner Name.
  5. Choose the Join Type.
    • Inner join: use when each record in the two tables has matching records.
    • Left outer join: output all records in the left table, even when the join condition does not match any records in the right table.
    • Right outer join: output all records in the right table, even when the join condition does not match any records in the left table.
    • Full outer: output all matching records from both tables. The records are output regardless of whether they are contained in both tables. In other words, if a record is in the left table and matches the criteria, it is output even though the same record is not in the right table.
  6. Enter the Join Condition of each join step. This is an expression to define the join condition. In this, only the first entry in the join condition consists of a Left join partner and a Right join partner. Every subsequent join condition has the previous join tree as Left join partner.
  7. Click Apply to return to the flowgraph editor.