Which of the following queries is most efficient for listing the names and capitals of each country?

Consider the numbers of row in the country and city tables:

mysql> SELECT COUNT(*) FROM Country;

Which of the following queries is most efficient for listing the names and capitals of each country?

Consider the numbers of row in the country and city tables:

mysql> SELECT COUNT(*) FROM Country;

Which of the following queries is most efficient for listing the names and capitals of each country?

A.
SELECT Country.name, City.name FROM Country, City WHERE Country.Capital=City.id

B.
SELECT Country.name, City.name FROM City, Country WHERE Country.Capital=City.id

C.
The queries are equally efficient.



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