Copy of the Vision of Britain g_link table prior to 2016 rebuild.

Table ID:

G_LINK_2015     (1247964)

Contents:

Copy of the Vision of Britain g_link table prior to 2016 rebuild.

Approx. number of rows:

52,309

Table type:

Raw Data

Documentation Author:

Humphrey Southall

Sources:

1. The "links" table has been built up by the Great Britain Historical GIS Project over many years, so it needs to be treated as primary data.

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Notes:

1. The following values of g_authority appear, based on systematically harvesting place-specific web pages within these sites:
   • GENUKI_WEB (11,348 links): Genealogy UK and Ireland, a very large site created by a network of genealogists.
   • GeoNames (15,127 links): Global gazetteer.
   • Hist_WkHse (731 links): History of the Workhouse, created by Peter Higginbottom.
   • VCH_Web (7,012 links): Victoria County History at British History Online.
   • Wikipedia (18,091 links).
2. The first version of the g_link table was a child table to our list of administrative units, but even the VCH was really more concerned with "places" so it is now a child table to g_place.

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Checking:

1. The table has been checked for internal consistency by setting up foreign key constraints to auo.g_authority and gbhdb.g_place_2015, but we cannot guarrantee that the external addresses work. As this table is intended as a permanent record of the pre-2016 system, over time more and more links will not work.

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Indices:

Index	Type	Column(s) indexed
g_link_2015_pkey	Primary key	g_place, g_url
g_link_2015_g_url_g_place_idx	Unique	g_url, g_place

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Constraints:

The table has the following associated constraints:

Constraint	Type	Details
g_link_2015_pkey	Primary Key	See details above for primary key index
g_link_2015_fk_place	Foreign Key	Column(s) {6} link to table g_place_2015, column(s) {1}.
g_link_ch_wk	Check	((((url_works)::text = 'N'::text) OR ((url_works)::text = 'Y'::text)))

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Columns within table:

Column	Type	Contents
g_authority	Text string (max.len.=24).	Identifier for the external site, as defined in our auo.g_authority table.
g_url	Text string (max.len.=204).	The URL of the page on the external site.
url_works	Text string (max.len.=5).	Flag column with values Y and N. It enables us to identify a particular external page as not working without actually removing it from our database. NB external sites, and especially GENUKI, sometimes change the format of their addresses, so they can be got working again by a global revision of the links we hold.
g_seq	Integer number.	Sequence number placing rows in order. This is particularly important where we have more than one link from one of our places to more than one page in a particular external site, which is common with our links to the Victoria County History.
g_url_label	Text string (max.len.=124).	Label to appear on the link when presented in the website. This will generally be the page title on the remote site, but given the kinds of page we link to this will often also be a place name.
g_place	Integer number.	ID number for the VoB place the link is for.
created_by	Text string (max.len.=64).	Name of the script which originally inserted current row into the table. This will generally also identify the source.