# Single-stage query engine (v1)

The Pinot single-stage query engine (v1) uses a scatter-gather query engine model, shown in the following diagram. In certain cases, for example, if you need to query using JOINs on large data sets, the [multi-stage query engine (v2)](https://docs.pinot.apache.org/release-1.0.0/reference/cluster-1) may be a more performant option. 

<figure><img src="https://content.gitbook.com/content/gYpmZ5dnYUh7aQjLUJ9b/blobs/W0yK1xN3DGFIYa5gZabH/Multi-Stage-Pinot-Query-Engine-v1.png" alt=""><figcaption><p>Single-stage query engine (v1)</p></figcaption></figure>