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

# Loop Node

> Iterate over a list of items and execute workflow logic for each item in DotPortion.

# Loop Node

The **Loop Node** allows you to **iterate over a list of items** and execute connected nodes **once for each item**.

It enables repetitive operations such as processing arrays, bulk database actions, or applying logic to multiple records — similar to a `for` or `forEach` loop in traditional programming.

***

## What the Loop Node Does

The Loop Node is responsible for:

* Iterating over an array or list of items
* Executing downstream nodes for each item
* Exposing the **current item** to child nodes
* Controlling repeated workflow execution

Each iteration runs **sequentially**, ensuring predictable execution.

***

<img src="https://mintcdn.com/dotportion/RvUelfRuZ_AGwzZr/images/nodes/loop.png?fit=max&auto=format&n=RvUelfRuZ_AGwzZr&q=85&s=55157ab291e13312154852dd6a140fde" alt="Loop" width="800" height="896" data-path="images/nodes/loop.png" />

## Configuration

### Items

The **Items** field defines the list you want to loop through.

It must resolve to an **array**.

You can:

* Write a JavaScript expression
* Reference dynamic values from previous nodes

> Tip: Type `{{` to insert dynamic node values.

***

## Providing Items to Loop Over

### Example: Loop over request body array

```js theme={null}
{{parameters.items}}
```

Request body:

```typescript theme={null}
{
  "items": [
    { "id": 1, "name": "Task A" },
    { "id": 2, "name": "Task B" }
  ]
}
```

***

### Example: Loop over database results

```typescript theme={null}
{{database.results}}
```

***

## Loop Execution Behavior

* The Loop Node runs once per item in the array
* During each iteration:
  * The **current item** is available to downstream nodes
  * Connected nodes execute in order
* After all items are processed, execution continues after the loop

***

## Accessing the Current Item

Inside the loop, the current item is available as:

```typescript theme={null}
{{item}}
```

Example usage in a Logic Node:

```typescript theme={null}
const current = {{item}};
return {
  id: current.id,
  processedAt: new Date().toISOString()
};
```

***

## Common Use Cases

* Bulk database inserts or updates
* Processing lists from request payloads
* Sending notifications for multiple users
* Transforming arrays of objects
* Applying validation per item

***

## Execution Rules

* Items must resolve to an array
* Empty arrays result in zero iterations
* Errors inside the loop stop execution immediately
* Loop execution is sequential, not parallel

***

## Common Mistakes

* Passing a non-array value to Items
* Forgetting to return data inside loop logic
* Assuming parallel execution
* Mutating shared state across iterations

***

## Best Practices

* Validate input before looping
* Keep logic inside loops lightweight
* Use loops only when necessary
* Prefer database bulk operations when supported
* Handle errors explicitly inside the loop

***

## Example: Bulk Create Tasks

**Items**

```typescript theme={null}
{{parameters.tasks}}
```

**Request Body**

```typescript theme={null}
{
  "tasks": [
    { "title": "Task 1" },
    { "title": "Task 2" }
  ]
}
```

Each task is processed one by one by downstream nodes.