Hugo Kornelis has a two-parter for us. First up is the inserted scan operator:
The Inserted Scan operator is only found in execution plans for code in triggers. It is used for queries that read data from the inserted pseudo-table. Its counterpart, Deleted Scan, reads from the deleted pseudo-table.
This pseudo-table contains a copy of all the rows that were inserted in AFTER INSERT triggers, or the new content of the data in all affected rows in AFTER UPDATE triggers. In INSTEAD OF INSERT or INSTEAD OF UPDATE triggers, the data in the inserted pseudo-table is the data that would have been inserted, or the data as it would have been after the update. In AFTER DELETE and INSTEAD OF DELETE triggers, using the inserted pseudo-table is allowed but returns no data.
This pseudo-table contains a copy of all rows that has just been deleted in AFTER DELETE triggers, or the original data of all affected rows in AFTER UPDATE triggers. In INSTEAD OF DELETE or INSTEAD OF UPDATE triggers, the data in the deleted pseudo-table is the current data in the rows that would have been deleted or updated. In AFTER INSERT and INSTEAD OF INSERT triggers, using the deleted pseudo-table is allowed but returns no data.
Click through to see how they work.