> 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/areas-and-zones-portfolio/code-point/code-point-technical-specification/supply-formats.md).
# Supply formats
## CSV and GeoPackage
GeoPackage is an open, standard, platform-independent, portable, self-describing, compact format for transferring geospatial information. For more information on this format, please see our [Getting started with GeoPackage guide](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-geopackage.md).
The following tables give a comparison between the CSV attributes and the GeoPackage attribution.
### CSV attribution and format
| Mnemonic | Description | Data type | Size |
| -------- | --------------------------------------------- | --------- | ---- |
| PC | Postcode | A8 | 8 |
| PQ | Postitional\_quality\_indicator | I2 | 1 |
| PR | PO\_Box\_indicator | A1 | 1 |
| TP | Total\_number\_of\_delivery\_points | I3 | \* |
| DQ | Delivery\_points\_used\_to\_create\_the\_CPLC | I3 | \* |
| RP | Domestic\_delivery\_points | I3 | \* |
| BP | Non\_domestic\_delivery\_points | I3 | \* |
| PD | PO\_Box\_delivery\_points | I3 | \* |
| MP | Matched\_address\_premises | I3 | \* |
| UM | Unmatched\_delivery\_points | I3 | \* |
| EA | Eastings | I6 | \* |
| NO | Northings | I7 | \* |
| CY | Country\_code | A9 | 9 |
| RH | NHS\_regional\_HA\_code | A9 | 9 |
| LH | NHS\_HA\_code | A9 | 9 |
| CC | Admin\_county\_code | A9 | 9 |
| DC | Admin\_district\_code | A9 | 9 |
| WC | Admin\_ward\_code | A9 | 9 |
| LS | Postcode\_type | A1 | 1 |
### GeoPackage attribution and format
| Description | Data type | Size |
| --------------------------------------------- | --------- | ---- |
| postcode | TEXT | 8 |
| positional\_quality\_indicator | TINYINT | 1 |
| po\_box\_indicator | TEXT | 1 |
| total\_number\_of\_delivery\_points | TINYINT | \* |
| delivery\_points\_used\_to\_create\_the\_cplc | TINYINT | \* |
| domestic\_delivery\_points | TINYINT | \* |
| non\_domestic\_delivery\_points | TINYINT | \* |
| po\_box\_delivery\_points | TINYINT | \* |
| matched\_address\_premises | TINYINT | \* |
| unmatched\_delivery\_points | TINYINT | \* |
| N/A | N/A | N/A |
| N/A | N/A | N/A |
| country\_code | TEXT | 9 |
| nhs\_regional\_ha\_code | TEXT | 9 |
| nhs\_ha\_code | TEXT | 9 |
| admin\_county\_code | TEXT | 9 |
| admin\_district\_code | TEXT | 9 |
| admin\_ward\_code | TEXT | 9 |
| postcode\_type | TEXT | 1 |
### CSV format
* Those fields containing text (A) will be enclosed by double quotes which have not been included in the sizes listed in the table above. An asterisk (\*) denotes variable length.
* Fields with null data will appear as "" for text and 0 for numeric.
* Each record will be terminated with a carriage return character (ASCII 13) and a line feed character (ASCII 10).
Example of a Code-Point CSV record: "SO160AS",10,"N",1,1,0,1,0,1,0,437292,115542,"E92000001","E19000002","E18000009","E10000014","E07000093","E05012936","L"
### GeoPackage format
Note that there are no eastings or northings in GeoPackage; the geometry is already created in the GeoPackage container and is not listed as data but will be seen as a column in a database (PostGIS) called *geom* with a coordinate reference system of British National Grid EPSG: 27700 for GB postcodes.
Also supplied with the GeoPackage is the Code-Point data for Northern Ireland. This is already projected in Irish Grid EPSG: 29902 so will display in the correct position for this region.
Fields with a null value will appear as \[Null] for text (PostGIS) or as an empty field in a GIS. A null numeric value will appear as 0 in both a database and an attribute table in a GIS.
The following screenshot is an example of a GeoPackage record taken from the Information tool in QGIS:
GeoPackage record as displayed in QGIS.
{% hint style="info" %}
The FeatureID (FID) is autogenerated by a GIS when the GeoPackage is loaded into it; it is not present in the GeoPackage.
{% endhint %}
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