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  • OS NGD Documentation
  • INTRODUCTION TO OS NGD
    • Introduction to OS NGD
    • OS NGD Explained
    • OS NGD Key Benefits to Customers
    • OS NGD Sample Data
    • OS NGD Product Viewer Tool
  • GETTING STARTED
    • Getting Started Information
    • OS NGD Fundamentals
      • Terminology and access
      • File formats and naming
      • Data ordering and currency
      • COU supplies
      • Data schema versioning
      • Unique identifiers
      • Coordinate reference systems
      • Attribute information for feature types
    • Downloading with OS Select+Build
      • Getting Started with GeoPackage
        • ArcGIS Pro
        • ArcMap
        • Cadcorp SIS
        • MapInfo Professional
        • QGIS
        • FME
        • GDAL
      • Getting Started with CSV
        • Loading CSV files
        • Processing COUs
      • Getting Started with Attribute Filtering
      • Getting Started with Temporal Filtering
    • Accessing OS NGD APIs
      • Getting started with an API project
      • OS NGD API – Features
        • What data is available?
        • Technical Specification
          • Landing page
          • Conformance
          • Collections
          • Collection
          • Schema
          • Queryables
          • Features
          • Feature
        • Getting Started
          • GIS Software
            • Cadcorp SIS
            • ESRI ArcGIS Online
            • ESRI ArcGIS Pro
            • QGIS
          • Libraries
            • Leaflet
            • MapLibre GL JS
            • OpenLayers
            • Python (Geopandas)
        • Code Examples
      • OS NGD API – Tiles
        • What data is available?
        • Zoom Levels
        • Technical Specification
          • Landing page
          • Conformance
          • Collections
          • Collection
          • Tile Matrix Sets
          • Tiles
          • Styles
        • Getting Started
          • GIS Software
            • Cadcorp SIS
            • QGIS
          • Libraries
            • Leaflet
            • MapLibre GL JS
            • OpenLayers
        • Code Examples
    • Styling OS NGD Data
    • OS NGD Webinars, Tutorials and Case Studies
    • FAQs
  • OS NGD NEWS
    • OS NGD News
    • What's New?
    • Change Log
    • OS NGD Improvements
    • Future OS NGD Data Enhancements
  • Data and Service Status
    • Data and Service Status Information
  • 🆕Live Service Disruption and Planned Maintenance
  • Current Known Data Issues
  • 🆕Resolved Data Issues
  • DATA STRUCTURE
    • Data Structure Information
    • OS NGD Address
      • GB Address
        • Built Address
        • Historic Address
        • Non-Addressable Object
        • Pre-Build Address
        • Street Address
      • Islands Address
        • Built Address
        • Historic Address
        • Non-Addressable Object
        • Pre-Build Address
        • Street Address
      • Related Components
        • Alternate Address
        • Postal Address
        • Other Classification
        • Related Entity
      • Versioning information
      • GB Address Local Custodian Codes
      • Islands Address Local Custodian Codes
    • OS NGD Administrative and Statistical Units
      • Boundaries
        • Boundary High Water Mark
        • Ceremonial County
        • Country
        • Devolved Parliament Constituency
        • Devolved Parliament Electoral Region
        • Electoral Division
        • GLA Assembly Constituency
        • Historic County
        • Historic European Region
        • Lower Tier Local Authority
        • Parish Or Community
        • Polling District
        • Region
        • Regional Authority
        • Upper Tier Local Authority
        • Ward
        • Westminster Constituency
    • OS NGD Buildings
      • Building Features
        • Building
        • 🆕Building Access Location
        • Building Line
        • Building Part
    • OS NGD Geographical Names
      • Named Features
        • 🆕Crowd Sourced Name Point
        • Named Area
        • Named Point
        • Named Road Junction
    • OS NGD Land
      • Land Features
        • Land
        • Land Point
        • Landform
        • Landform Line
        • Landform Point
    • OS NGD Land Use
      • Land Use Features
        • Site
        • Site Access Location
        • ❌Site Routing Point
    • OS NGD Structures
      • Structure Features
        • Compound Structure
        • Field Boundary
        • Structure
        • Structure Line
        • Structure Point
    • OS NGD Transport
      • Routing and Asset Management Information (RAMI)
        • Average And Indicative Speed
        • Highway Dedication
        • Maintenance Area
        • Maintenance Line
        • Maintenance Point
        • Reinstatement Area
        • Reinstatement Line
        • Reinstatement Point
        • Restriction
        • Routing Hazard
        • Routing Structure
        • Special Designation Area
        • Special Designation Line
        • Special Designation Point
      • Transport Features
        • Cartographic Rail Detail
        • Rail
        • Road Line
        • Road Track Or Path
        • 🆕Street Light
      • Transport Network
        • Connecting Link
        • Connecting Node
        • Ferry Link
        • Ferry Node
        • Ferry Terminal
        • Path
        • Path Link
        • Path Node
        • Pavement Link
        • Railway Link
        • Railway Link Set
        • Railway Node
        • Road
        • Road Junction
        • Road Link
        • Road Node
        • Street
        • Tram On Road
    • OS NGD Water
      • Water Features
        • Inter Tidal Line
        • River Basin District Catchment
        • Tidal Boundary
        • Water
        • Water Point
        • Waterbody Catchment
      • Water Network
        • Water Link
        • Water Link Set
        • Water Node
  • Code Lists
    • Code Lists Overview
      • accesstypevalue
      • 🆕accesslevelvalue
      • 🆕accessmodevalue
      • 🆕accessobstructionvalue
      • 🆕accesspurposevalue
      • addressbasepostalvalue
      • addressclassificationsourcevalue
      • addressdescriptionvalue
      • addressstatusvalue
      • addressstreettypevalue
      • associatedstreetdatadescriptionvalue
      • averageandindicativespeeddescriptionvalue
      • basementpresencesourcevalue
      • boundaryhighwatermarkdescriptionvalue
      • boundarytypevalue
      • 🆕buildingaccesslocationdescriptionvalue
      • buildingageperiodvalue
      • buildingagesourcevalue
      • buildingconnectivitytypevalue
      • buildingdescriptionvalue
      • buildinglinedescriptionvalue
      • buildingpartdescriptionvalue
      • buildingpartoslandcovertieravalue
      • buildingpartoslandcovertierbvalue
      • buildingusevalue
      • buildstatusvalue
      • builtstructureheightconfidencevalue
      • capturemethodvalue
      • capturespecificationvalue
      • ceremonialcountydescriptionvalue
      • changetypevalue
      • classificationcorrelationvalue
      • compoundstructuredescriptionvalue
      • connectinglinkdescriptionvalue
      • connectingnodedescriptionvalue
      • constructionmaterialsourcevalue
      • constructionmaterialvalue
      • countryvalue
      • countrydescriptionvalue
      • 🆕crowdsourcednamedescriptionvalue
      • 🆕crowdsourcednamematchtypevalue
      • cyclefacilityvalue
      • dataentitycatalogue
      • dedicationvalue
      • devolvedparliamentconstituencydescriptionvalue
      • devolvedparliamentelectoralregiondescriptionvalue
      • electoraldivisiondescriptionvalue
      • extentoflinkvalue
      • ferrylinkdescriptionvalue
      • ferrynodedescriptionvalue
      • ferryterminaldescriptionvalue
      • fieldboundarydescriptionvalue
      • formofroadnodevalue
      • formofwaytypevalue
      • gaugevalue
      • glaassemblyconstituencydescriptionvalue
      • gssrolevalue
      • hazardtypevalue
      • heightingmethodvalue
      • highwaydedicationnetworkfeaturetypevalue
      • historiccountydescriptionvalue
      • historiceuropeanregiondescriptionvalue
      • intertidallinedescriptionvalue
      • 🆕illuminationvalue
      • junctiontypedescriptionvalue
      • landdescriptionvalue
      • landformdescriptionvalue
      • landformlinedescriptionvalue
      • landformpointdescriptionvalue
      • landoslandcovertieravalue
      • landoslandcovertierbvalue
      • landformvalue
      • landpointdescriptionvalue
      • languagevalue
      • linkdirectionvalue
      • 🆕linkreferenceconfidencevalue
      • lowertierlocalauthoritydescriptionvalue
      • maintenancevalue
      • 🆕matchedfeaturetypengdvalue
      • 🆕matchedthemengdvalue
      • matchstatusvalue
      • classificationcorrelationvalue
      • namedareaextentdefinitionvalue
      • nameddatevalue
      • nameddayvalue
      • namedescriptiongroupvalue
      • namedescriptionvalue
      • namedperiodvalue
      • namedroadjunctiondescriptionvalue
      • namedtimevalue
      • networkfeaturetypevalue
      • 🆕networknodefeaturetypevalue
      • networkoverunderbridgevalue
      • operationalstatevalue
      • operationalstatusvalue
      • oslandusetieravalue
      • oslandusetierbvalue
      • parentboundarydescriptionvalue
      • parentfeaturetypevalue
      • parishorcommunitydescriptionvalue
      • pathdescriptionvalue
      • pathnodedescriptionvalue
      • physicallevelvalue
      • 🆕physicalstatevalue
      • physicallevelvalue
      • pollingdistrictdescriptionvalue
      • positionalaccuracyvalue
      • postcodetypevalue
      • presencevalue
      • raildescriptionvalue
      • raildetaildescriptionvalue
      • railoslandcovertieravalue
      • railoslandcovertierbvalue
      • railwaylinkdescriptionvalue
      • railwaylinksetdescriptionvalue
      • railwaynodedescriptionvalue
      • railwayusevalue
      • regionalauthoritydescriptionvalue
      • regiondescriptionvalue
      • reinstatementtypevalue
      • relationshiptypevalue
      • restrictiontypedescriptionvalue
      • restrictionvalue
      • riverbasindistrictcatchmentdescriptionvalue
      • roadclassificationvalue
      • roaddescriptionvalue
      • roadfunctionvalue
      • roadlinedescriptionvalue
      • roadnodedescriptionvalue
      • roadstructurevalue
      • roadtrackorpathdescriptionvalue
      • roadtrackorpathoslandcovertieravalue
      • roadtrackorpathoslandcovertierbvalue
      • roadwidthconfidencelevelvalue
      • 🆕roofconfidenceindicatorvalue
      • 🆕roofmaterialvalue
      • 🆕roofshapevalue
      • pavementdescriptionvalue
      • sideofroadvalue
      • siteaccesslocationdescriptionvalue
      • sitedescriptionvalue
      • siteextentdefinitionvalue
      • siteroutingpointdescriptionvalue
      • sourceofmeasurevalue
      • specialdesignationtypevalue
      • stakeholdervalue
      • statusvalue
      • streetclassificationvalue
      • streetdescriptionvalue
      • streetgeometrysourcevalue
      • 🆕streetlightdescriptionvalue
      • streetstatevalue
      • streetsurfacevalue
      • streettypevalue
      • structuredescriptionvalue
      • structureoslandcovertieravalue
      • structureoslandcovertierbvalue
      • structurelinedescriptionvalue
      • structurepointdescriptionvalue
      • structuretypevalue
      • structurevalue
      • surfacetypevalue
      • themevalue
      • tidalboundarydescriptionvalue
      • trackrepresentationvalue
      • tramdescriptionvalue
      • 🆕transportfeaturetypevalue
      • uppertierlocalauthoritydescriptionvalue
      • usrnmatchindicatorvalue
      • vehiclequalifiervalue
      • warddescriptionvalue
      • waterbodycatchmentdescriptionvalue
      • waterbodycategoryvalue
      • waterdescriptionvalue
      • wateroslandcovertieravalue
      • wateroslandcovertierbvalue
      • waterlinkdescriptionvalue
      • waterlinkflowdirectionvalue
      • waterlinkgeometrysourcevalue
      • waterlinklevelofdetailvalue
      • waterlinkpermanencevalue
      • waterlinkphysicalcontainmentvalue
      • waterlinkprimacyvalue
      • waterlinksetdescriptionvalue
      • waterlinkwatertypevalue
      • watermarkvalue
      • waternodedescriptionvalue
      • waterpointdescriptionvalue
      • watertypevalue
      • westminsterconstituencydescriptionvalue
      • yesnovalue
  • USING OS NGD DATA
    • OS NGD Buildings
      • Building Feature Type
      • How Building data is created
      • Building attribution
      • Known limitations
      • Summary
    • OS NGD Structures
      • Field Boundary
        • Field Boundary Feature Type
        • How Field Boundary data is created
        • Field Boundary attribution
        • Known limitations
        • Summary
    • OS NGD Transport
      • Pavements
        • Pavement polygons
        • Pavement attribution
        • Pavement Link feature type
      • Trams
        • Tram attribution on Road Link
        • Tram On Road Feature Type
        • Trams in the Rail Network
      • Street Light
        • Known limitations
    • OS NGD Land Cover Enhancements
      • Introduction
      • Habitat mapping
      • Percentage coverage
      • Cross reference table
      • Known limitations
      • Summary
  • EXTRA LINKS
    • Accessibility
    • Data Catalogue
    • Contact Us
    • Copyright
    • PSGA Product Summary
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  1. GETTING STARTED
  2. OS NGD Fundamentals

Unique identifiers

The OS NGD will primarily use a new identifier called the OSID (OS Identifier) to uniquely identify features. The OSID will be used persistently and will allow the unique identification of records in the OS NGD. It should be noted that the OSID will not be unique across the OS NGD, but rather only unique at a feature type level. The reason for this is, when possible, the same OSID will be used on multiple features when they represent the same geographical feature. For example, a point feature in the OS NGD Geographical Names Theme which represents a water body will have the same OSID as the more detailed water body representation in the OS NGD Water Features Theme.

Other unique identifiers are also present in the OS NGD. These include the UPRN (Unique Property Reference Number) and USRN (Unique Street Reference Number). These will remain the unique identifiers in our data to represent Address and Local Authority Street records respectively.

The TOID (Topographic Identifier) is also present in the OS NGD, but in most instances this is an optional attribute and therefore should not be relied upon to complete data linking or for implementing COUs. The reason for this identifier being optional is the improved currency on which the OS NGD will be published, meaning the TOID which is created in our existing OS product systems will not always be allocated to features as frequently as they will be accessible via the OS NGD.

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Last updated 1 year ago

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