Consider the country table.
mysql> DESCRIBE COUNTRY;
Which of the following queries will produce a list of all continents along with their largest country?
A.
SELECT continent, name, surfacearea FROM Country AS co2 WHERE co2.surfacearea = (SELECT MAX(surfacearea) FROM Country AS col WHERE co2.continent=col.continent GROUP BY col.continent)
B.
SELECT continent, name, surfacearea FROM Country AS co2 WHERE co2.surfacearea = (SELECT MAX(surfacearea) FROM Country AS col GROUP BY col.continent)
C.
SELECT continent, name, surfacearea FROM Country AS co2 WHERE co2.surfacearea > (SELECT surfacearea FROM Country AS col WHERE co2.continent=col.continent GROUP BY col.continent)
D.
SELECT continent, name, surfacearea FROM Country AS co2 WHERE co2.surfacearea > (SELECT surfacearea FROM Country AS col GROUP BY col.continent)
E.
SELECT continent, name, surfacearea FROM Country WHERE surfacearea = (SELECT MAX(surfacearea) FROM Country GROUP BY continent)
Explanation:
B doesn’t say how tables are joined, C > not = (largest country = Max), D > not =, E table name is ambiguous.