1 For each left table row, read all right table rows from the beginning until one is found that can be joined with it.
2 Produce the join result.
If no matching right table rows are found, return the left row.
Note: Teradata Database does not support dynamic row partition elimination for exclusion product joins for 8‑byte partitioning.
The following request returns the names of those employees who do not work in Chicago:
SELECT name
FROM employee
WHERE dept_no NOT IN (SELECT dept_no
FROM department
WHERE loc = ’CHI’);
Because the subquery returns only one row, the Optimizer selects an exclusion product join for the join plan using with the following process:
1 All AMPs are searched for department rows where loc = ‘CHI’.
2 The single row found to satisfy this condition, that for department 600, is duplicated right away, without being spooled in the local AMP.
3 The rows in the two spools undergo an exclusion product join on each AMP.
4 Name information for any employee row whose dept_no is not 600 is placed in a result spool on each AMP.
5 When the last AMP has completed its portion of the join, the contents of all results spools are sent to the requesting application via a BYNET merge.
The following graphic illustrates this process: