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If you say, "List the books priced less than $10 and more than $30," the and suggests the use of the AND operator:
SELECT title_name, price
WHERE price < 10 AND price > 30; --Wrong
This query returns no rows, however, because it's impossible for a book to be priced less than $10 and more than $30 simultaneously, as AND logic commands. The logical meaning of OR finds books that meet any of the criteria, not all the criteria at the same time:
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