> For the complete documentation index, see [llms.txt](https://v2.dataos.info/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://v2.dataos.info/references/v1/resources/vulcan/concepts/query-result-caching.md).

# Query result caching

Vulcan reuses the result of an identical query when its underlying data is still current. This provides faster responses and avoids repeating unnecessary warehouse work.

## When results are reused

Result reuse is available for all supported query experiences:

* SQL queries
* Semantic queries, including REST, SQL, and GraphQL requests
* Metric queries
* Saved perspective refreshes

Vulcan can return a previously computed result when a new request matches the earlier request in all of the following ways:

* **Query definition:** the same SQL, semantic query, or metric query.
* **Query inputs:** the same filters, parameters, dimensions, date range, sorting, and pagination settings.
* **Execution context:** the same selected data source.

The response indicates that the existing result was reused and includes when it was originally computed.

If an identical query is already running, Vulcan joins that in-progress request instead of starting duplicate work. The result is available once the original request finishes.

## Keeping results current

Vulcan tracks the data products used by each query result. When a successful data refresh updates any of those dependencies, affected results are no longer reused. The next request runs again and produces a fresh result.

For externally managed data sources, Vulcan also respects their configured refresh schedule. A result is refreshed after the source reaches its next scheduled refresh boundary.

## How result reuse works

```mermaid
sequenceDiagram
    participant Client
    participant Vulcan
    participant Warehouse
    participant ObjectStorage

    Client->>Vulcan: Submit query
    Vulcan->>Vulcan: Check for a current matching result
    alt Current result available
        Vulcan-->>Client: Confirm the existing result is available
    else No current result available
        Vulcan->>Warehouse: Run query
        Warehouse->>ObjectStorage: Store completed result
        ObjectStorage-->>Vulcan: Confirm result is available
        Vulcan-->>Client: Confirm the new result is available
    end

    Client->>Vulcan: Request result
    alt File download
        Vulcan-->>Client: Provide a temporary download link
        Client->>ObjectStorage: Download result
        ObjectStorage-->>Client: Return result file
    else JSON, CSV, or YAML response
        Vulcan->>ObjectStorage: Retrieve result
        ObjectStorage-->>Vulcan: Return result data
        Vulcan-->>Client: Return formatted result
    end

    Warehouse->>Vulcan: Scheduled or on-demand data refresh completes successfully
    Vulcan->>Vulcan: Mark affected query results for refresh
```

## Receiving query results

Vulcan stores completed query results in your configured cloud object storage. This allows large results to be delivered efficiently while keeping the query experience consistent across supported storage providers.

For a result-file download, Vulcan provides a temporary download link and your client retrieves the file directly from cloud object storage. For JSON, CSV, or YAML responses, Vulcan retrieves the result and returns it in the requested format.

## What to expect

* Reused results are returned more quickly than a new warehouse execution.
* Results remain reusable only while their dependent data is current.
* A successful refresh of relevant data automatically makes the next matching query run again.
* Each query request remains traceable, including requests that reuse an existing result.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## 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, and the optional `goal` query parameter:

```
GET https://v2.dataos.info/references/v1/resources/vulcan/concepts/query-result-caching.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.