> For the complete documentation index, see [llms.txt](https://dshub.gitbook.io/ds-hub/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dshub.gitbook.io/ds-hub/sql/sql-practice/popular-websites-for-sql-practice/sqlzoo/world-bbc-tables/sum-and-count-tutorial.md).

# SUM and COUNT Tutorial

[Link](https://sqlzoo.net/wiki/SUM_and_COUNT)

1. Show the total population of the world.

```
SELECT SUM(population) FROM world
```

2. List all the continents - just once each.

```
SELECT Distinct continent FROM world
```

3. Give the total GDP of Africa

```
SELECT SUM(GDP) FROM world WHERE continent = 'Africa'
```

4. How many countries have an area of at least 1000000

```
SELECT COUNT(name) FROM world WHERE area >= 1000000
```

5. What is the total population of ('Estonia', 'Latvia', 'Lithuania')

```
SELECT SUM(population) FROM world 
WHERE name IN ('Estonia', 'Latvia', 'Lithuania')
```

6. For each continent show the continent and number of countries.

```
SELECT continent, COUNT(name) 
FROM world
GROUP BY continent
```

7. For each continent show the continent and number of countries with populations of at least 10 million.

```
SELECT continent, COUNT(name) 
FROM world
WHERE population > 10000000
GROUP BY continent
```

8. List the continents that have a total population of at least 100 million.

```
SELECT continent, SUM(population) 
FROM world
GROUP BY continent
HAVING SUM(population) > 100000000
```