# 595\_Big Countries

There is a table`World`

```
+-----------------+------------+------------+--------------+---------------+
| name            | continent  | area       | population   | gdp           |
+-----------------+------------+------------+--------------+---------------+
| Afghanistan     | Asia       | 652230     | 25500100     | 20343000      |
| Albania         | Europe     | 28748      | 2831741      | 12960000      |
| Algeria         | Africa     | 2381741    | 37100000     | 188681000     |
| Andorra         | Europe     | 468        | 78115        | 3712000       |
| Angola          | Africa     | 1246700    | 20609294     | 100990000     |
+-----------------+------------+------------+--------------+---------------+
```

A country is big if it has an area of bigger than 3 million square km or a population of more than 25 million.

Write a SQL solution to output big countries' name, population and area.

For example, according to the above table, we should output:

```
+--------------+-------------+--------------+
| name         | population  | area         |
+--------------+-------------+--------------+
| Afghanistan  | 25500100    | 652230       |
| Algeria      | 37100000    | 2381741      |
+--------------+-------------+--------------+
```

## Solution 1: use OR to combine two conditions

```php
SELECT name, population, area
FROM World
WHERE area > 3000000 OR population > 25000000;
```

## Solution 2: use UNION to combine results under two conditions

```php
SELECT name, population, area
FROM World
WHERE area > 3000000 

UNION

SELECT name, population, area
FROM World
WHERE population > 25000000
;
```

Note: In this question, **union is much faster than or.**


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