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

# Add a pre-aggregation

> Hands-on walkthrough of accepting a Playground pre-aggregation suggestion, updating the data model, and rerunning an accelerated query.

In this step, we'll add a pre-aggregation to optimize the performance of a
specific query. Pre-aggregations are a caching technique that massively reduces
query time from seconds to milliseconds. They are extremely useful for speeding
up queries that are run frequently.

From the **Build** tab, execute a query:

<Frame>
  <img src="https://ucarecdn.com/aadc3670-10ba-42af-8f69-0f8fb5c31c2d/" alt="Cube Developer Playground Screen showing query results" />
</Frame>

Just above the results, click on **Query was not accelerated with
pre-aggregation** to bring up the pre-aggregation suggestion:

<Frame>
  <img src="https://ucarecdn.com/0f5c4d2a-b37a-4eb6-865d-8f1121246e96/" alt="Cube Developer Playground Screen showing pre-aggregation suggestion" />
</Frame>

A pre-aggregation will be automatically suggested for the query;
click **Add to the Data Model** and then retry the query in the
Playground. This time, the query should be accelerated with a pre-aggregation:

<Frame>
  <img src="https://ucarecdn.com/1cf669e6-fb54-4a01-bbb5-b49943e36689/" alt="Cube Developer Playground Screen querying a pre-aggregation" />
</Frame>

And with that, we conclude our Getting Started with Cube guide. If you'd like to
learn more about Cube, [check out this page][next].

[next]: /docs/getting-started/core/learn-more