> ## Documentation Index
> Fetch the complete documentation index at: https://docs.farmtrace.co.za/llms.txt
> Use this file to discover all available pages before exploring further.

# Null handling functions

> Detect missing values and select a usable fallback.

A `null` value means that data is unavailable. Empty text is still text and may need separate handling with `Len` or `Trim`.

## `IsNull`

Checks whether a value is `null`.

* **Syntax:** `IsNull(value)`
* **Requires:** any one value.
* **Returns:** Boolean.
* **Best for:** choosing a fallback or avoiding work that requires a value.

```text theme={"theme":{"light":"github-light","dark":"github-dark"}}
If(IsNull([Due Date]), "No due date", Format([Due Date], "dd MMM yyyy"))
```

## `Nz`

Returns the first non-null value.

* **Syntax:** `Nz(value)` or `Nz(value, fallback[, fallback...])`
* **Requires:** one or more values. When fallbacks are supplied, all non-null values must have the same type.
* **Returns:** the first non-null value. With one null argument, returns empty text; if every supplied fallback is null, returns `null`.
* **Best for:** defaults that preserve the intended value type.

```text theme={"theme":{"light":"github-light","dark":"github-dark"}}
Nz([Preferred Name], [Full Name], "Unnamed")
```

<Warning>
  `Nz` does not treat empty text, zero, or `false` as null.
</Warning>