Working with Subqueries
Filtering with a Subquery
Filtering with CTE
Filtering with EXISTS
Subqueries as Calculated Fields
Subquery in the JOIN Statement
Updating With a Subquery
Deleting With a Subquery
DELETE
FROM
country
WHERE
NOT
EXISTS
(
SELECT
1
FROM
city
WHERE
city.
CountryCode
= country.
Code
)
Deleting countries without cities.