> ## Documentation Index
> Fetch the complete documentation index at: https://axiom-mano-sample-app.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Conditional functions

> Learn how to use and combine different conditional functions in APL

## Conditional functions

| **Function Name** | **Description**                                                                                             |
| ----------------- | ----------------------------------------------------------------------------------------------------------- |
| [case()](#case)   | Evaluates a list of conditions and returns the first result expression whose condition is satisfied.        |
| [iff()](#iff)     | Evaluates the first argument (the predicate), and returns the value of either the second or third arguments |

## case()

Evaluates a list of conditions and returns the first result whose condition is satisfied.

### Arguments

* condition: An expression that evaluates to a Boolean.
* result: An expression that Axiom evaluates and returns the value if its condition is the first that evaluates to true.
* nothingMatchedResult: An expression that Axiom evaluates and returns the value if none of the conditional expressions evaluates to true.

### Returns

Axiom returns the value of the first result whose condition evaluates to true. If none of the conditions is satisfied, Axiom returns the value of `nothingMatchedResult`.

### Example

```kusto
case(condition1, result1, condition2, result2, condition3, result3, ..., nothingMatchedResult)
```

```kusto
['sample-http-logs'] |
extend status_human_readable = case(
    status_int == 200,
    'OK',
    status_int == 201,
    'Created',
    status_int == 301,
    'Moved Permanently',
    status_int == 500,
    'Internal Server Error',
    'Other'
)
```

[Run in Playground](https://play.axiom.co/axiom-play-qf1k/query?initForm=%7B%22apl%22%3A%22%5B'sample-http-logs'%5D%5Cn%7C%20extend%20status_code%20%3D%20case\(status_int%20%3D%3D%20200%2C%20'OK'%2C%20status_int%20%3D%3D%20201%2C%20'Created'%2C%20status_int%20%3D%3D%20301%2C%20'Moved%20Permanently'%2C%20status_int%20%3D%3D%20500%2C%20'Internal%20Server%20Error'%2C%20'Other'\)%22%7D)

## iff()

Evaluates the first argument (the predicate), and returns the value of either the second or third arguments. The second and third arguments must be of the same type.

### Arguments

* predicate: An expression that evaluates to a boolean value.
* ifTrue: An expression that gets evaluated and its value returned from the function if predicate evaluates to `true`.
* ifFalse: An expression that gets evaluated and its value returned from the function if predicate evaluates to `false`.

### Returns

This function returns the value of ifTrue if predicate evaluates to true, or the value of ifFalse otherwise.

### Examples

```kusto
iff(predicate, ifTrue, ifFalse)
```

```kusto
['sample-http-logs']
| project Status = iff(req_duration_ms == 1, "numeric", "Inactive")
```

[Run in Playground](https://play.axiom.co/axiom-play-qf1k/query?initForm=%7B%22apl%22%3A%22%5B'sample-http-logs'%5D%5Cn%7C%20project%20Status%20%3D%20iff%28req_duration_ms%20%3D%3D%201%2C%20%5C%22numeric%5C%22%2C%20%5C%22Inactive%5C%22%29%22%7D)