Instead of creating a dataset from the ground up, and thus geocoding your data using the "By Admin. Regions" option. You can download a dataset which contains the info you are interested in. That's something not only for working with CartoDB. This is common for other webmapping application or GIS desktop tool (before you start to read about how to get the dataset and visualize it with CartoDB. I highly recommend you to go and ask (or maybe it is already posted) in Open Data Stack Exchange).
In this case, in order to get a dataset with Wales, Northern Ireland and England geometries you can go to Eurostat. Click on NUTS 2013 (Nomenclature Administrative Units for Statistics), and download the first shapefile of the list. CartoDB allows you to import the whole zip file. Once it is imported, you will see several new datasets in your dashboard. We are going to use
nuts_rg_01m_2013. This is the map view:
As you can observe, you need to select and join the small units or NUTs for each of the countries/regions (England, Scotland, Nothern Ireland and Wales). Here you have a very useful resource that will help you to know which code you need to select. For instance, all the NUTs that start with
UKN are from Northern Ireland. Using the SQL console:
ST_Union(the_geom_webmercator) as the_geom_webmercator,
WHEN nuts_id ilike 'UKN%' THEN 'Northern Ireland'
WHEN nuts_id ilike 'UKL%' THEN 'Wales'
END AS region
nuts_id ~ 'UK[N|C-L].*'
I have used
the_geom_webmercator instead of
the_geom in order to see the changes. But you can use the later and create a new dataset from the query. This is the resulting map:
Finally, in order to join this dataset with yours, first you will need to add the same columns (with the same data type) and then run the following SQL command (substituting the name of the datasets):