Describe a scenario for which a find unmatched query could be used.

unmatched query can be used when you use one table to store data about an item, and another table to store data about items movement such as sales that involve that thing. To determine which items are idle these stored information is not enough because the item movements table includes data only about items that have been sold. You must compare the two tables to determine which items are idle. In such situations this query is used