Subquery inside SELECT
As explored in the video, there are often multiple ways to produce the same result in SQL. You saw that subqueries can provide an alternative to joins to obtain the same result.
In this exercise, you'll go further in exploring how some queries can be written using either a join or a subquery.
In Step 1, you'll begin with a LEFT JOIN combined with a GROUP BY to select the nine countries with the most cities appearing in the cities table, along with the counts of these cities. In Step 2, you'll write a query that returns the same result as the join, but leveraging a nested query instead.
This exercise is part of the course
Joining Data in SQL
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
-- Find top nine countries with the most cities
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-- Order by count of cities as cities_num
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-- Limit the results
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