# Filter, Sort, Aggregate and Remove Duplicates — AI Automation with n8n

Source: https://www.geekswithgeeks.com/en/n8n-ai-automation/data-builtin-nodes

> Use built-in data nodes before reaching for the Code node.

## Prefer a built-in node when one exists

n8n has ready-made nodes for common data jobs: **Filter** keeps items matching a condition, **Sort** orders them, **Limit** keeps the first N, **Remove Duplicates** drops repeats by a key, **Aggregate** combines many items into one list, and **Summarize** computes counts, sums and averages. They are easier to read and maintain than equivalent Code, and teammates who do not code can edit them.

## A typical daily report chain

Each line is a node. The AI step receives one compact summary rather than hundreds of raw rows, which also saves tokens.

```text
HTTP Request        fetch yesterday's orders (200 items)
 -> Filter           status is "paid"
 -> Remove Duplicates  by order id
 -> Summarize        count, sum(total) grouped by region
 -> Aggregate        all groups into one list
 -> Basic LLM Chain  "Write a 3-line sales summary from this data"
```

## Summarise before the AI step

Sending hundreds of raw rows to a model is slow, costly and noisy. Reduce the data with Filter and Summarize first, then give the model only what it needs to write or decide.

**Quiz:** Which node combines many items into a single list item?

- [ ] Wait
- [ ] Error Trigger
- [ ] Webhook
- [x] Aggregate

*Answer:* Aggregate. Aggregate merges the incoming items so the next node, such as an LLM, sees them together.