> 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/os-emergency-services-gazetteer/os-esg-technical-specification/structured-data-types.md).

# Structured data types

These pages describe the two data types available for the OS Emergency Services Gazetteer (OS ESG):

* [LPI (Type 24 Record)](/os-downloads/products/addresses-and-names-portfolio/os-emergency-services-gazetteer/os-esg-technical-specification/structured-data-types/lpi-type-24-record.md)
* [Classification (Type 32 Record)](/os-downloads/products/addresses-and-names-portfolio/os-emergency-services-gazetteer/os-esg-technical-specification/structured-data-types/classification-type-32-record.md)

The attributes associated with each data type are listed on the following pages. The following information can be found about each attribute:

### Name and Definition

The name of the attribute and what it is describing.

### Data Types

The values the attribute can take. For example, a numeric value or a string. This is provided for both data formats – GeoPackage and CSV.

### Precision

The maximum total number of decimal digits to be stored. This number includes both the left and the right sides of the decimal point. The precision must be a value from 1 through the maximum precision of 38. The SQL Server default precision is 18.

### Scale

Scale (*s*) is the number of decimal digits that are stored to the right of the decimal point. This number is subtracted from precision (*p*) to determine the maximum number of digits to the left of the decimal point. Scale must be a value from 0 through *p*, and can only be specified if precision is specified. The default scale is 0 and so 0 <= *s* <= *p*. Maximum storage sizes vary, based on the precision.

### Code List Name

The name of the code list used in association with the attribute (if applicable) and a hyperlink to the page displaying that code list.

### Size / Max Length

Values are given here to indicate the maximum length that you will find in the attribute, to aid in developing applications.

### Nullable

A True or False value to denote whether the attribute always has to be populated with a value (False) or can be NULL (True).

### Data Schema Version

The schema version the data above applies to.


---

# 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/os-emergency-services-gazetteer/os-esg-technical-specification/structured-data-types.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.