SUM and COUNT Quiz

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SUM and COUNT QUIZ <quiz shuffle=none display=simple> {Select the statement that shows the sum of population of all countries in 'Europe' |type="()"} -A. SELECT name, population FROM bbc WHERE region = 'Europe' -B. SELECT population FROM bbc WHERE region = 'Europe' SUM BY region +C. SELECT SUM(population) FROM bbc WHERE region = 'Europe' -D. SELECT SUM(population FROM bbc WHERE region = 'Europe') -E. SUM population FROM bbc WHERE region = 'Europe'

{Select the statement that shows the number of countries with population smaller than 150000 |type="()"} +A. SELECT COUNT(name) FROM bbc WHERE population < 150000 -B. SELECT COUNT(population < 150000) FROM bbc -C. SELECT name FROM bbc WHERE population < 150000 -D. SELECT population AS COUNT FROM bbc WHERE population < 150000 -E. SELECT SUM() FROM bbc WHERE population < 150000

{Select the full set of SQL aggregate functions |type="()"} -A. AVG(), COUNT(), FIRST(), LAST(), SUM() -B. AVG(), COUNT(), MAX(), MEDIAN(), MIN(), ROUND(), SUM() +C. AVG(), COUNT(), FIRST(), LAST(), MAX(), MIN(), SUM() -D. AVG(), COUNT(), MAX(), MIN(), SUM() -E. COUNT(), SUM()

{Select the statement that shows the average population of 'Poland', 'Germany' and 'Denmark' |type="()"} -A. SELECT AVG(population) FROM bbc WHERE name = ('Poland', 'Germany', 'Denmark') +B. SELECT AVG(population) FROM bbc WHERE name IN ('Poland', 'Germany', 'Denmark') -C. SELECT AVG(population) FROM bbc WHERE name LIKE ('Poland', 'Germany', 'Denmark') -D. SELECT AVG(population) FROM bbc WHERE name LIKE (Poland, Germany, Denmark) -E. SELECT population FROM bbc WHERE name IN ('Poland', 'Germany', 'Denmark')

{Select the statement that shows the medium population density of each region |type="()"} -A. SELECT region, AVG(population/area) AS density FROM bbc -B. SELECT region, COUNT(population)/COUNT(area) AS density FROM bbc GROUP BY region -C. SELECT region, SUM(population)/COUNT(area) AS density FROM bbc GROUP BY region -D. SELECT region, SUM(population)/SUM(area) AS density FROM bbc HAVING region +E. SELECT region, SUM(population)/SUM(area) AS density FROM bbc GROUP BY region

{Select the statement that shows the name and population density of the country with the largest population |type="()"} -A. SELECT name, density AS population/area FROM bbc WHERE population = MAX(population) -B. SELECT name, density AS population/area FROM bbc WHERE population = (SELECT MAX(population) FROM bbc) -C. SELECT name, MAX (population) FROM bbc WHERE population / (SELECT area FROM bbc) +D. SELECT name, population/area AS density FROM bbc WHERE population = (SELECT MAX(population) FROM bbc) -E. SELECT name, population/area AS density FROM bbc WHERE population > (SELECT MAX(population) FROM bbc)

</quiz>