# Multi-Stage Query

For an overview of when to use the multi-stage engine (MSE) versus the single-stage engine (SSE), see [Query Engines (SSE vs MSE)](/build-with-pinot/querying-and-sql/sse-vs-mse.md). This section provides a deep dive into MSE internals. Most of the concepts explained here are related to the engine's execution model and are not required for writing queries. However, understanding them can help you take advantage of MSE's capabilities and troubleshoot issues.


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.pinot.apache.org/build-with-pinot/querying-and-sql/multi-stage-query.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.