# Routing Structure

These indicate the location of key structures related to the highway network. These may be:

* Barriers: Structures or equipment constructed to control, obstruct, or prevent passage or access
* Bridges and Tunnels
* Crossings and Signals: Equipment such as traffic signals, and locations that control the flow of traffic

## Temporal filtering

The earliest date on which you can request a one-off snapshot of a date in the past for data in this feature type is 29 September 2022.

Any data temporally filtered earlier than the specified earliest date noted above for the data schema version may contain data inconsistencies.

## Feature type attributes

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

{% hint style="info" %}

## Loading OS NGD CSV files into databases

Comma-separated values (CSV) file format is universally supported for easy ingestion into all major database products. Before loading OS NGD data contained in CSV files into a database, it is necessary to create relevant tables. Data definition language (DDL) statements for PostgreSQL, SQL Server and Oracle can be accessed in our [OS NGD Resources GitHub repository](https://github.com/OrdnanceSurvey/osngd-resources/tree/main/database-resources).

For instructions on loading CSV files, see the [Getting Started with CSV](https://docs.os.uk/osngd/accessing-os-ngd/downloading-with-os-select+build/getting-started-with-csv/loading-csv-files) guide.
{% endhint %}

### osid

Primary identifier for the feature. The OSID is a Globally Unique Identifier (GUID) and requires no centralised authority to ensure uniqueness. Note that the same OSID can occur in more than one feature type when a single feature is represented multiple times in the OS NGD.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Max Length:** 36
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### toid

Topographic Identifier (TOID) of the feature, as published in the OS MasterMap suite of products.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 20
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### versiondate

Date when the version was last updated.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### versionavailablefromdate

The date this version of the feature became the latest version.

* **Data Types:** String (GeoJSON), DateTime (GPKG), DateTime (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### versionavailabletodate

The date this version of the feature was superseded by an update or ceased to exist.

* **Data Types:** String (GeoJSON), DateTime (GPKG), DateTime (CSV)
* **Nullable:** true
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### changetype

The type of change that generated a new version of the feature.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [changetypevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/changetypevalue)
* **Max Length:** 50
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### geometry

Geometry for the feature.

* **Data Types:** Geometry (GeoJSON), Geometry (GPKG), WKT (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0
* **Geometry Type:** MultiLineString

### geometry\_length

The measured length of the geometry in metres.

* **Data Types:** Number (GeoJSON), Float (GPKG), Real (CSV)
* **Nullable:** false
* **Precision:** 15
* **Scale:** 6
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### theme

The OS NGD theme to which this feature belongs.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [themevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/themevalue)
* **Max Length:** 40
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### description

A single descriptive value intended for a quick understanding of what the feature represents.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [structuretypevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/structuretypevalue)
* **Max Length:** 39
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** Yes
* **Data Schema Version:** 1.0

### structuredescription

Additional information describing the structure.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 50
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### atpositionxcoordinate

The X,Y coordinates of a point along a road link or the X,Y coordinates of the Road Node.

* **Data Types:** Number (GeoJSON), Float (GPKG), Real (CSV)
* **Nullable:** true
* **Precision:** 10
* **Scale:** 3
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### atpositionycoordinate

The X,Y coordinates of a point along a road link or the X,Y coordinates of the Road Node.

* **Data Types:** Number (GeoJSON), Float (GPKG), Real (CSV)
* **Nullable:** true
* **Precision:** 10
* **Scale:** 3
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

***

## Routing Structure Network Reference

### networkreferenceid

The identifier of the network reference feature.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Max Length:** 36
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### networkfeaturetype

The type of network feature referenced.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [networkfeaturetypevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/networkfeaturetypevalue)
* **Max Length:** 9
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### routingstructureid

The identifier for the Routing Structure feature.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Max Length:** 36
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0

### routingstructureversiondate

The date this version of the feature entered the OS National Geographic Database.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** true
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.0


---

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