Unique values
Part of the Fundamentals section of Coddy's SQL journey — lesson 4 of 72.
Let's assume we have the following table:
sales
| country | city | amount | |
|---|---|---|---|
| 1 | Poland | Warsaw | 13 |
| 2 | Germany | Berlin | 24 |
| 3 | Poland | Katowice | 56 |
And we would like to know all of the countries where the product was sold.
If we use the normal query we know: SELECT country from sales it will return Poland, Germany, Poland. This is not what we are looking for because Poland is repeated twice.
To solve it we can use the DISTINCT keyword:
SELECT DISTINCT country FROM sales
Challenge
EasyAvailable tables and columns:
<strong>sales</strong>:<strong>coin</strong>,<strong>amount</strong>
Fetch all of the unique coins that were used in the sales table
Try it yourself
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
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