---
title: Facets
description: Compute a Top N and aggregate in one query
canonical: https://docs.paradedb.com/documentation/aggregates/facets
---

A common pattern in search is to query for both an aggregate and a set of search results. For example, "find the top 10
results, and also count the total number of results."

Instead of issuing two separate queries -- one for the search results, and another for the aggregate -- `pdb.agg` allows for
these results to be returned in a single "faceted" query. This can significantly improve read throughput, since issuing a single
query uses less CPU and disk I/O.

For example, this query returns the top 3 search results alongside the total number of results found.

```sql
SELECT
  id, description, rating,
  pdb.agg('{"value_count": {"field": "id"}}') OVER ()
FROM mock_items
WHERE category === 'electronics'
ORDER BY rating DESC
LIMIT 3;
```

```ini Expected Response
 id |         description         | rating |      agg
----+-----------------------------+--------+----------------
 12 | Innovative wireless earbuds |      5 | {"value": 5.0}
  1 | Ergonomic metal keyboard    |      4 | {"value": 5.0}
  2 | Plastic Keyboard            |      4 | {"value": 5.0}
(3 rows)
```

<Note>
  Faceted queries require that `pdb.agg` be used as a window function:
  `pdb.agg() OVER ()`.
</Note>