> 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/resources/product-resources/end-of-life-product-documentation/os-mastermap-water-network-layer/os-mastermap-water-network-layer-technical-specification/vector-tiles-overview/attribute-naming-differences.md).

# Attribute naming differences

## Attribute naming differences between GML and vector tiles formats <a href="#id-6.2-attribute-naming-differences-between" id="id-6.2-attribute-naming-differences-between"></a>

The naming of attributes between vector tiles and the Geography Markup Language (GML) file is very similar as the vector tiles set within the MBTiles file is not limited in the number of characters for an attribute name.

### WatercourseLink

The following table maps the GML attribute name to the attribute name in the vector tiles for WatercourseLink:

| GML Attribute              | Vector Tiles Attribute         |
| -------------------------- | ------------------------------ |
| gml:id                     | toid                           |
| fictitious                 | fictitious                     |
| form                       | form                           |
| level                      | level                          |
| provenance                 | provenance                     |
| flowDirection              | flow\_direction                |
| primacy                    | primacy                        |
| watercourseNumber          | watercourse\_number            |
| watercourseName            | watercourse\_name              |
| watercourseNameAlternative | watercourse\_name\_alternative |
| localNameLang              | local\_name                    |
| localNameAlternative       | local\_name\_alternative       |
| catchmentName              | catchment\_name                |
| permanence                 | permanence                     |
| managedNavigation          | managed\_navigation            |
| length                     | length                         |
| length\_uom                | length\_uom                    |
| gradient                   | gradient                       |
| width                      | width                          |
| width\_uom                 | width\_uom                     |
| levelOfDetail              | level\_of\_detail              |

### HydroNode

The following table maps the GML attribute name to the attribute name in the vector tiles for HydroNode:

| GML Attribute     | Vector Tiles Attribute |
| ----------------- | ---------------------- |
| gml\_id           | toid                   |
| hydronodecategory | hydronode\_category    |


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