> For the complete documentation index, see [llms.txt](https://metis-montessori-lyceum.gitbook.io/sql-0/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://metis-montessori-lyceum.gitbook.io/sql-0/2-selectie-voorwaarden-en-sorteren/de-where.md).

# WHERE

Als je bepaalde rijen wilt selecteren die voldoen aan één of meerdere voorwaarden, dan gebruik je `WHERE`.

In het volgende voorbeeld maken we een lijstje van de Klanten die in "Spanje" wonen.

De query wordt:

```sql
Select *
From Customer
Where Country = 'Spain';
```

De basis syntax voor de query is:

```sql
Select <kolommen>
From <tabel>
Where <voorwaarde>;
```

In de voorwaarde zit altijd een operator, je kunt de volgende operatoren in SQL gebruiken:

| Operator | Betekenis                      |
| -------- | ------------------------------ |
| =        | is gelijk aan                  |
| <        | is kleiner dan                 |
| >        | is groter dan                  |
| <=       | is kleiner of gelijk aan       |
| >=       | is groter of gelijk aan        |
| <>       | is niet gelijk aan             |
| between  | ligt tussen                    |
| in       | is een van de volgende waarden |

**2.4 Oefening**

Welke klanten hebben de voornaam "Mark"? (geef de voornaam en de achternaam)


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