Use `IFNULL` to replace NULL values in your data with a more suitable or meaningful value. This can be helpful when you want to avoid displaying NULLs in your charts or when you need a specific value for further calculations.

## Sample usage

`IFNULL(Discount, 0)`

## Syntax

`IFNULL( input_expression, null_result )`

### Parameters

- **`input_expression`** -- The expression to evaluate. You can use any valid expression as the `input_expression`.

- **`null_result`** -- The value to return if `input_expression` is null. If `input_expression` is not null, `IFNULL` returns the `input_expression`. You can use any valid expression as the `null_result`.

## Example

Calculate the average discount given to your customers, including orders that received no discount. However, your application sometimes represents "no discount" as null rather than 0.

The formula `AVG(Discount)` won't include null discounts. You'll need to convert those nulls to zero. To do this, create a new field called, for example, **Discount No Nulls**:

`IFNULL(Discount, 0)`

This formula can be read, "If the **Discount** field is null, return 0, otherwise return **Discount**."

You can then calculate the average discount including orders with no discount:

`AVG(Discount No Nulls)`