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# Aggregations
You can perform aggregation queries through beanie as well. For example, to calculate the average:
```python
# With a search:
avg_price = await Product.find(
Product.category.name == "Chocolate"
).avg(Product.price)
# Over the whole collection:
avg_price = await Product.avg(Product.price)
```
A full list of available methods can be found [here](../api-documentation/interfaces.md/#aggregatemethods).
You can also use the native PyMongo syntax by calling the `aggregate` method.
However, as Beanie will not know what output to expect, you will have to supply a projection model yourself.
If you do not supply a projection model, then a dictionary will be returned.
```python
class OutputItem(BaseModel):
id: str = Field(None, alias="_id")
total: float
result = await Product.find(
Product.category.name == "Chocolate").aggregate(
[{"$group": {"_id": "$category.name", "total": {"$avg": "$price"}}}],
projection_model=OutputItem
).to_list()
```
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