> For the complete documentation index, see [llms.txt](https://docs.wem.io/platform/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.wem.io/platform/wemreference/functions/aggregation/first.md).

# First

{% hint style="info" %}
The **`First()`** function returns the <mark style="color:green;">first item</mark> in a <mark style="color:blue;">list</mark> or <mark style="color:blue;">concept set</mark>.

This function is NOT SQL compatible. For more information about SQL compatibility, see our [documentation](/platform/wemreference/sql-compatibility.md).
{% endhint %}

{% hint style="success" %}
Returns the <mark style="color:green;">first</mark> item in the given <mark style="color:blue;">`list`</mark> or <mark style="color:blue;">`concept_set`</mark>.

Returns <mark style="color:red;">**`Unknown`**</mark> if one of the parameter values is unknown or outside the common valid date boundaries.
{% endhint %}

{% hint style="info" %}
First() and Last() on a database list use the RowID for standard sorting - so \
`First([Name] of [Products])` will get the name-fieldvalue of the **first** item created, and \
`Last([Name] of [Products])` will get the name-fieldvalue of the **last** item created.&#x20;

You can limit/specify the resultlist using the WHERE options, and within that resultlist, the lowest or highest RowID will be returned.

*In future we will add the \[Order By] syntax to WEM Expressions, so you can specify the order yourself in the expression, and then the First and Last will use that sorting.*

In some specific cases if you want the First/Last item based on another fieldvalue, like LastModified, you could use something like

`First([list] WHERE [LastModified] = Max([LastModified] of [List]))`
{% endhint %}

### Syntax

<details>

<summary><code>First(</code><mark style="color:blue;"><code>list</code></mark><code>)</code></summary>

`First(List("A", "B", "C"))`\
\=>*Result: "A"*

`First([Products] where [Product.Price] > 10)`\
\=>*Result: returns the first row of products that cost more than 10 euro*

`First([Products] WHERE [LastModified] = Max([LastModified] of [Products]))`\
\=>*Result: returns the last modified item in products (first row of products that has been modified last)*

`First()`\
\=>*Result: unknown*

</details>

<details>

<summary><code>First(</code><mark style="color:blue;"><code>concept_set</code></mark><code>)</code></summary>

`First({ Color.Orange, Color.Blue, Color.Red })`\
\=>*Result: Color.Orange*

`First()`\
\=>*Result: unknown*

</details>

### Parameters

<table><thead><tr><th width="180.20869378712746">Name</th><th width="150">Type</th><th width="150" align="center">Required</th><th width="248.15953250810662">Description</th><th data-hidden>Required?</th></tr></thead><tbody><tr><td><mark style="color:blue;"><code>list</code></mark></td><td>List of elements of the same type</td><td align="center"><span data-gb-custom-inline data-tag="emoji" data-code="2611">☑️</span></td><td>a list of values or elements of the same type. </td><td>yes</td></tr><tr><td><mark style="color:blue;"><code>concept_set</code></mark></td><td>A list of concepts</td><td align="center"><span data-gb-custom-inline data-tag="emoji" data-code="2611">☑️</span></td><td>a list of concepts</td><td>yes</td></tr></tbody></table>


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