Retrieving Multiple Columns
Let's find out a little more about this database. A country database contains one table, named country. Let's look at this table.
This table has 15 rows. In other words, we have 15 different records for different countries.
What about columns? Here we have 7 columns, like id, name, continent, region,
SurfaceArea, capital and population.
1. id - the record number of this table
2. name - the name of the country
3. continent - the name of the country's continent;
4. region- the name of the country's region
5. SurfaceArea - the surface area of the country
6. capital - the capital of the country
7. population - the population of the country.
We can also retrieve multiple columns with the SELECT operator. The only difference is that after the word SELECT, we will need to specify several column names, which must be separated by a comma. Let’s take an example where we retrieve three columns from the country table.
12SELECT id, name, capital FROM country;
Swipe to start coding
You have to retrieve the continent and population columns from the country table.
Solution
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Let's find out a little more about this database. A country database contains one table, named country. Let's look at this table.
This table has 15 rows. In other words, we have 15 different records for different countries.
What about columns? Here we have 7 columns, like id, name, continent, region,
SurfaceArea, capital and population.
1. id - the record number of this table
2. name - the name of the country
3. continent - the name of the country's continent;
4. region- the name of the country's region
5. SurfaceArea - the surface area of the country
6. capital - the capital of the country
7. population - the population of the country.
We can also retrieve multiple columns with the SELECT operator. The only difference is that after the word SELECT, we will need to specify several column names, which must be separated by a comma. Let’s take an example where we retrieve three columns from the country table.
12SELECT id, name, capital FROM country;
Swipe to start coding
You have to retrieve the continent and population columns from the country table.
Solution
Passez à un bureau pour une pratique réelleContinuez d'où vous êtes en utilisant l'une des options ci-dessousMerci pour vos commentaires !
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