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3. Range Check
A range check is commonly used when you are working with data which consists of numbers, currency or dates/times.
A range check is a validation rule that sets upper / lower limits to the allowed values for that field.
Here are some examples of types of range check you might use to validate database data.
| Boundary | Description | Validation Rule |
|---|---|---|
| Upper limit | The maximum price of any item in a shop is £100 | <=100 |
| Lower limit | In a shop, you cannot sell a negative number of items, however you can sell no items | >=0 |
| A range | to achieve a B grade you must score between 75% - 84% | >=75 AND <=84 |
| A date range | Must be a valid date |
Challenge see if you can find out one extra fact on this topic that we haven't already told you
Click on this link: Database Validation