c0mm0.com — the continuously verified register of European data

Cross-source linking

Linking identifiers

The shared keys that let data be joined across French public sources — a parcel number, an INSEE commune code, an IRIS zone, a BAN address id, an RNB building id, a SIREN/SIRET. For each, this catalog shows how many sources expose it, under which raw field names, and whether it can be used as a filter in API requests (useful for sequential, drill-down calls). It's the map we'll link data with.

Based on 203 French sources with a classified field, out of 333 currently profiled. Updated 2026-07-02 07:51 UTC.

Territorial — administrative geography

INSEE COG codes that pin data to a commune, département, région or EPCI.

EPCI / intercommunalité (SIREN)

38

sources · 7 field names

join key33 joinable2 callable35 filterable

INSEE / DGCL (BANATIC)

Code commune INSEE (COG)

57

sources · 19 field names

join key49 joinable3 callable52 filterable

INSEE (Code Officiel Géographique)

Code département

51

sources · 9 field names

join key45 joinable2 callable46 filterable

INSEE (Code Officiel Géographique)

Code région

56

sources · 7 field names

join key51 joinable2 callable48 filterable

INSEE (Code Officiel Géographique)

Code postal

35

sources · 6 field names

22 joinable2 callable28 filterable

La Poste

Statistical zoning

Fine-grained census geography (IRIS).

IRIS (zone statistique)

18

sources · 4 field names

join key11 joinable17 filterablecomposite

INSEE

Cadastre

Land parcels and their components.

Parcelle cadastrale (IDU)

4

sources · 4 field names

join key1 callable4 filterablecomposite

DGFiP / IGN (cadastre, API Carto)

Section cadastrale

1

source · 1 field name

1 joinable1 filterable

DGFiP / IGN

Buildings

Building-level pivot keys (RNB, BD TOPO).

Identifiant RNB (bâtiment)

1

source · 1 field name

join key1 joinable1 filterable

RNB (CSTB / IGN)

Cleabs (IGN BD TOPO)

1

source · 1 field name

join key1 joinable1 filterable

IGN (BD TOPO)

Identifiant bâtiment (générique)

0

sources

varies

Addresses

Postal/address references (BAN, FANTOIR).

Code FANTOIR (voie)

1

source · 1 field name

join key1 filterable

DGFiP

Identifiant adresse BAN

2

sources · 2 field names

join key1 joinable1 filterable

BAN (Base Adresse Nationale)

Adresse (texte)

35

sources · 34 field names

21 filterable

varies

Organisations

Legal units and establishments (SIREN/SIRET).

SIRET (établissement)

47

sources · 14 field names

join key11 joinable32 callable41 filterable

INSEE (SIRENE)

SIREN (unité légale)

51

sources · 13 field names

join key14 joinable33 callable45 filterable

INSEE (SIRENE)

Coordinates & geometry

Spatial linking via points or geometry.

Coordonnées (lat/lon WGS84)

88

sources · 24 field names

join key20 joinable5 callable78 filterablecomposite

WGS84 (EPSG:4326)

Géométrie

82

sources · 7 field names

join key1 callable79 filterable

OGC / GeoJSON

How to read this

  • Joinable counts sources whose real sample values match the key's expected format (e.g. genuine 5-char INSEE codes) — those are directly joinable today; the higher source count is the candidate pool.
  • Coverage is limited to French sources we've already profiled — others appear as they get profiled.
  • “Filterable” is authoritative for Opendatasoft/DataFair facets and inferred structurally for feature services (WFS/OGC API Features/ArcGIS). For plain OpenAPI REST APIs it's unknown, because query parameters aren't captured yet.
  • Field→identifier matching is alias/pattern-based — it may miss exotic spellings; composite keys (parcel, IRIS, lat+lon) are flagged but not auto-assembled.