Exercise

Correlated sub-query

Sub-queries are used to retrieve information from another table, or query, that is separate to the main query.

A friend is working on a project looking at earthquake hazards around the world. She requires a table that lists all countries, their continent and the average magnitude earthquake by country. This query will need to access data from the Nations and Earthquakes tables.

Instructions 1/2

XP

1
2

Add the average magnitude column in the sub-query.
Add the Nations country code column reference in the sub-query.

Take Hint (-15 XP)