GB Postcodes

The server importing instructions allow optionally download gb_postcode_data.sql.gz. This document explains how the file got created.

GB vs UK

GB (Great Britain) is more correct as the Ordnance Survey dataset doesn't contain postcodes from Northern Ireland.

Importing separately after the initial import

If you forgot to download the file, or have a new version, you can import it separately:

Import the downloaded gb_postcode_data.sql.gz file.
Run the SQL query SELECT count(getorcreate_postcode_id(postcode)) FROM gb_postcode;. This will update the search index.
Run utils/setup.php --calculate-postcodes from the build directory. This will copy data form the gb_postcode table to the location_postcodes table.

Converting Code-Point Open data

Download from Code-Point® Open. It requires an email address where a download link will be send to.

unzip codepo_gb.zip

Unpacked you'll see a directory of CSV files.

$ more codepo_gb/Data/CSV/n.csv
"N1 0AA",10,530626,183961,"E92000001","E19000003","E18000007","","E09000019","E05000368"
"N1 0AB",10,530559,183978,"E92000001","E19000003","E18000007","","E09000019","E05000368"

The coordinates are "Northings" and "Eastings" in OSGB 1936 projection. They can be projected to WGS84 like this

SELECT ST_AsText(ST_Transform(ST_SetSRID('POINT(530626 183961)'::geometry,27700), 4326));
POINT(-0.117872733220225 51.5394424719303)

-0.117872733220225 51.5394424719303 on OSM map

Create database, import CSV files, add geometry column, dump into file

DBNAME=create_gb_postcode_file
createdb $DBNAME
echo 'CREATE EXTENSION postgis' | psql $DBNAME

cat data/gb_postcode_table.sql | psql $DBNAME      
cat codepo_gb/Data/CSV/*.csv | ./data-sources/gb-postcodes/convert_codepoint.php | psql $DBNAME
cat codepo_gb/Doc/licence.txt | iconv -f iso-8859-1 -t utf-8 | dos2unix | sed 's/^/-- /g' > gb_postcode_data.sql
pg_dump -a -t gb_postcode $DBNAME | grep -v '^--' >> gb_postcode_data.sql

gzip -9 -f gb_postcode_data.sql
ls -lah gb_postcode_data.*
# dropdb $DBNAME