> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/feature-types/addressbase-supply-set.md).

# AddressBase Supply Set

This feature is formally known as the GML feature collection and is used to define a collection of features.

{% hint style="info" %}
This is not supplied as part of the CSV supply. Please see the model overviews in [AddressBase Plus structure](/os-downloads/products/addresses-and-names-portfolio/addressbase-plus/addressbase-plus-technical-specification/addressbase-plus-structure.md) for more information.
{% endhint %}

## Feature type attributes <a href="#feature-type-attributes" id="feature-type-attributes"></a>

The following sub-sections provide details about the attributes included with this feature, their data types in the different output formats, and other important metadata about them.

### Query time

Time the data was extracted from the database.

* **Attribute Name**: queryTime (GML), Not provided (CSV)
* **Data Type:** DateTime
* **Multiplicity**: \[1]

### Query change since date

{% hint style="info" %}
This attribute is only provided as part of a Change Only Update (COU) supply. It will not be provided if you take a Full Supply.
{% endhint %}

The date given as part of a change-only query.

* **Attribute Name**: queryChangeSinceDate (GML), Not provided (CSV)
* **Data Type:** Date
* **Multiplicity**: \[0..1]


---

# 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://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus-islands/addressbase-plus-islands-technical-specification/feature-types/addressbase-supply-set.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.