Date on which the metadata was last updated, or was confirmed as being up-to-date,
or if not updated, then the date it was created
Purpose and meaning
This is the date at which the metadata can be considered current (rather than the
dataset itself). It may be the date at which the metadata was reviewed and confirmed
as
being 'current'. It is used to distinguish which of two records with the same fileIdentifier
the system will keep.
Obligation
Mandatory
Occurrence
Single
Data type
Date
Domain
Single date as specified by BS ISO 8601 in the extended date format (YYYY-MM-DD),
where YYYY is the year, MM is the month and DD is the day. Time (HH:MM:SS, where HH
is the
hour, MM the minutes and SS the seconds) may be added if required, separated from
the day
by 'T'.
Guidance
This should be updated whenever the metadata is updated due to a change in the
dataset, or when it is reviewed and confirmed as wholly correct.
The date should be at an appropriate level of resolution (e.g. the day, or the day
and month).
The date should not be in the future.
Comment
If the metadata has not been updated, then this should be the date when it was
created.
The encoding example for metadata date is shown in Example One. Note that it is
possible to record the date and time of the metadata instance using the encoding shown
in
Example Two.
This is used to distinguish which of two records with
the same fileIdentifier the system will keep. Even if the records are moved to a different
server, if the fileIdentifier and metadata date are the same, the harvester will not
collect
the new files.
Name : Metadata language
UK GEMINI id
33
Definition
Language used for documenting the metadata
Purpose and meaning
The purpose of this is to identify the language used in a multi-lingual metadata
service, for example in the INSPIRE geo-portal.
Obligation
Mandatory
Occurrence
Single
Data type
CharacterString
Domain
Free text
Guidance
It is recommended to select a value from a controlled vocabulary, for example that
provided by ISO 639-2 which uses three-letter primary tags with optional subtags.
The values for the UK are:
English
eng
Welsh
cym*
Irish
gle
Gaelic (Scottish)
gla
Cornish
cor
Ulster Scots
sco
*ISO 639/2 has two codes for Welsh: textual ('cym') and
bibliographic ('wel'). For GEMINI we recommend using cym, which abbreviates
that language's own name for itself.
In general, a default value of 'eng' can be applied.
If there is only a small amount of metadata in a second language, e.g. Alternative
title, then Metadata language should still indicate the main language.
Comment
For INSPIRE, the metadata itself must be in one of the official European
languages, such as English or Irish.
Metadata language missing Metadata language is optional in ISO 19115 and GEMINI
2.2, but mandatory for INSPIRE and therefore in GEMINI 2.3. This is now checked by
the UK
Location GEMINI schematron.
Name : Metadata point of contact
UK GEMINI id
35
Definition
Party responsible for the creation and maintenance of the metadata
Purpose and meaning
This is the organisation or role in an organisation responsible for this
metadata.
Obligation
Mandatory
Occurrence
Multiple
Data type
CharacterString
Domain
Free text
Guidance
Should include organisation name and contact email address, as described under
Responsible party.
Comment
Examples
Large-scale Topographic Data Manager, Ordnance Survey.
To support the operation of UK Location and INSPIRE, discovery metadata records must
include a File Identifier for the resource.
Obligation
Mandatory
Occurrence
Single
Data type
CharacterString
Domain
Free text
Guidance
File Identifier must be populated with a unique identifier. This may be a UUID
generated by a metadata creation tool. Once created and published to UK
Location, the File Identifier must not be changed. A change to the File Identifier would represent the creation of a new resource.
If the UK Catalogue receives two records with the same File Identifier, the one
with the more recent metadata date will be retained.
Persistence and uniqueness across the metadata infrastructure are key
Only use characters that are allowed in URIs (RFC3986), in particular, do not use
curly brackets
The first XML child element of any GEMINI2 metadata instance shall be
gmd:fileIdentifier. The content of this XML element is the identifier of the metadata
instance. File identifier is not a metadata item of GEMINI2. It is not to be confused
with the metadata item Resource identifier.
The content of the XML element shall be a unique managed identifier, such as a
system generated UUID. Once the identifier has been set for a metadata instance it
shall not change.
Name of the metadata standard or profile used.
The relevant standard shall be cited with a reference to the appropriate register
entry.
Purpose and meaning
The purpose of this element is to record the metadata standard (profile) followed
when creating the metadata.
This will be important when metadata is passed from one metadata system to another.
GEMINI is supported by a register of metadata standard and profile names, hosted on the NERC vocab server.
The relevant standard shall be cited with a reference to the appropriate register
entry, using an Anchor.
Example
Example One – UK GEMINI 2.3
<gmd:MD_Metadata>
...
<gmd:metadataStandardName>
<gmx:Anchor xlink:href="http://vocab.nerc.ac.uk/collection/M25/current/GEMINI/">UK GEMINI</gmx:Anchor>
</gmd:metadataStandardName>
<gmd:metadataStandardVersion>
<gco:CharacterString>2.3</gco:CharacterString>
</gmd:metadataStandardVersion>
...
</gmd:MD_Metadata>
Example Two – MEDIN profile of GEMINI 2.3
...
<gmd:metadataStandardName>
<gmx:Anchor xlink:href="http://vocab.nerc.ac.uk/collection/M25/current/MEDIN/">MEDIN</gmx:Anchor>
</gmd:metadataStandardName>
<gmd:metadataStandardVersion>
<gco:CharacterString>3.0</gco:CharacterString>
</gmd:metadataStandardVersion>
...
The purpose of this element is to provide a readily recognisable name for the
resource.
Obligation
Mandatory
Occurrence
Single
Data type
CharacterString
Domain
Free text
Guidance
The name should be readily recognisable
The title should be the formal or product name for the data resource, if
existing.
If no name exists, then a title should be created that is short, encapsulates the
subject, temporal and spatial coverage of the data resource, and does not contain
terms or jargon that make it incomprehensible.
Acronyms are acceptable in the Title providing they are fully expanded in the
abstract or Alternative Title.
Comment
Examples
OS MasterMap Topography Layer
Voter participation in Liverpool local elections, 1994, by ward
Short name, other name, acronym or alternative language title for the data
resource
Purpose and meaning
The purpose of this element is to record any alternative titles by which the data
resource is known.
Obligation
Optional
Occurrence
Multiple
Data type
CharacterString
Domain
Free text
Guidance
Should be provided when the data resource has more than one title.
There is no need to fill in this entry unless there are other names used for the
dataset, for example historic names.
Commonly used abbreviations or acronyms should be recorded. If the acronym or
abbreviation has been used in the main Title, then use the full name in the
Alternative Title.
Other language equivalents should be recorded where they exist, for example the
Welsh language title (although this title may refer to a different data
resource).
If there is no textual information in the data resource, then the special code value
zxx of ISO 639-2/B reserved for "no linguistic content; not applicable" shall
be used.
Note that according to the ISO 19115 logical model the language property is typed
as
a CharacterString. The use of the gco:CharacterString type is permitted by the ISO
19139 schemas but this approach shall not be used to encode GEMINI2 metadata. Instead
the XML element gmd:LanguageCode, which substitutes for gco:CharacterString, shall
be
used.
The XML element gmd:LanguageCode is implemented as a code list element. Note that
the codeList attribute should have the following value in GEMINI2 metadata instances:
http://www.loc.gov/standards/iso639-2/php/code_list.php
Note however, that this URL resolves to an HTML web page rather than a service
endpoint providing ISO 639-2 language codes.
Example
Example following the INSPIRE recommendation of using the name of the language as
the
content of the gmd:LanguageCode
The abstract should provide a clear and concise statement that enables the reader
to
understand the content of the data or service
Obligation
Mandatory
Occurrence
Single
Data type
CharacterString
Domain
Free text
Guidance
The abstract should provide a clear statement of the content of
the data and not general background information.
State what the 'things' are that are recorded.
State the key aspects recorded about these things.
State what form the data takes.
State any other limiting information, such as time period of validity of the
data.
Add purpose of data resource where relevant (e.g. for survey data).
Include a description of the extent or location.
Include legal references.
Aim to be understood by non-experts.
Do not include general background information.
Avoid jargon and unexplained abbreviations.
Acronyms should be expanded to the full name along with the abbreviated version at
the beginning of the abstract. The abbreviated version can then be used (see examples
below).
Note: the Schematron validation will raise an error if the abstract is less than 100
characters, or is the same as the title.
Comment
The most important details of the description should be summarised in the first
sentence, or the first 256 characters.
Examples
This file contains the digital vector boundaries for Lower Layer Super Output Areas
(LSOA) as at 31 December 2011 in England and Wales.
This file contains the National Statistics Postcode Lookup (NSPL) for the United
Kingdom as at February 2017.
<gmd:MD_Metadata>
...
<gmd:identificationInfo>
<gmd:MD_DataIdentification id="BGS-13603180">
...
<gmd:abstract>
<gco:CharacterString>The data shows polygonal and selected linear geological information, sourced from published
BGS 1:625 000 scale maps of Great Britain.
However, geological units are identified using the most up-to-date nomenclature that may differ from that on the
printed maps. The maps are generally based on published material at 1:50 000 scale and compiled using techniques of
selection, generalisation and exaggeration. The geology is fitted to a relevant topographic base at the time of
production. Full UK coverage is available. The data is available in vector format. BGS licensing terms and
conditions apply to external use of the data.
</gco:CharacterString>
</gmd:abstract>
...
</gmd:MD_DataIdentification>
</gmd:identificationInfo>
...
</gmd:MD_Metadata>
information pertaining to earth
sciences Examples: geophysical features and processes, geology, minerals,
soils
health
009
health, health services, human ecology, and
safety Examples: disease and illness, factors affecting health, health
services
imageryBaseMapsEarthCover
010
base maps Examples: land
cover, topographic maps, imagery, unclassified images
intelligenceMilitary
011
military bases, structures,
activities Examples: barracks, training grounds, military
transportation
inlandWaters
012
inland water features, drainage systems and
their characteristics Examples: rivers, salt lakes, dams, floods, water
quality, hydrographic charts
location
013
positional information and services Examples:
addresses, geodetic networks, control points, postal zones and services, place
names
oceans
014
features and characteristics of salt water
bodies (excluding inland waters) Examples: tides, tidal waves, coastal
information, reefs
planningCadastre
015
information used for appropriate actions
for future use of the land Examples: land use maps, zoning maps, cadastral
surveys, land ownership
society
016
characteristics of society and cultures
Examples: settlements, anthropology, archaeology, education, demographic data,
recreational areas and activities, social impact assessments, crime and justice,
census information
structure
017
man-made construction Examples: buildings,
museums, churches, factories, housing, monuments, shops
transportation
018
means and aids for conveying persons and/or
goods Examples: roads, airports/airstrips, shipping routes, tunnels, nautical
charts, vehicle or vessel location, aeronautical charts, railways
utilitiesCommunication
019
energy, water and waste systems and
communications infrastructure and services Examples: sources of energy, water
purification and distribution, sewage collection and disposal, electricity and gas
distribution, data communication, telecommunication, radio
Guidance
Select one or more categories that most closely represent the topic of the data resource.
If in doubt, go by the topic categories rather than the examples.
It is not necessary to include all categories which may be applicable, but only a
limited
number of most relevant should be chosen (e.g. topographic maps should not be classified
as farming).
Comment
For greater detail within a topic, use the element Keyword
The encoding example for topic category is shown in Example One. Note that it is
possible to include more than one topic category.
The value of the XML element gmd:MD_TopicCategoryCode must not contain whitespace
because the values are specified by an enumerated list in the XSD schemas. The
encoding shown in Example Two, for example, will result in an XSD schema validation
error because the element content will be parsed as shown in Example 3 (excluding
the
square brackets denoting the start and end) resulting in a value that does not exist
in the enumerated list.
The purpose of this element is to indicate the general subject area of the data
resource using keywords. This enables searches to eliminate resources that are of
no
interest. Ideally, a standardised set of keywords should be used, so that resources
can be
identified in any search. This element is similar to Topic category, which has a coded list of
high-level categories, whereas Keyword allows more appropriate terms to describe the
data
resource.
Obligation
Mandatory
Occurrence
Multiple
Data type
Class
Domain
This class comprises the following elements:
Keyword value (mandatory)
Originating controlled vocabulary (conditional - if keywords originate from a controlled
vocabulary)
These are specified as follows:
Keyword value
Originating controlled vocabulary
Definition
topic of the content of the data resource
name of the formally registered thesaurus or a similar authoritative source of
keywords
Obligation
mandatory
conditional - required if keywords
originate from a controlled vocabulary
Occurrence
multiple
single
Data type
CharacterString
Class CI_Citation (from
ISO19115)
Domain
free text
The following properties are expected:
title of type character string (free text)
reference date defined as
a date type (creation, revision or publication)
an effective date
Other Comments
-
a default value will generally be assigned for
this
Guidance
Keyword values should if possible be taken from a list of standard subject
categories, identified in the element 'Originating controlled
vocabulary'.
The GEMINI2 keyword item comprises keyword value(s) and, conditionally, the
specification of an originating controlled vocabulary. If keywords are not selected
from a controlled vocabulary the encoding shown in Example One shall be used.
Where keywords do originate from a controlled vocabulary the encoding shown in
Example Two shall be used. Note the inclusion of the gmd:thesaurusName XML element
which contains the XML element gmd:CI_Citation. This element must contain at least
a
title, reference date and date type. In the example keywords have been selected from
the GEMET Concepts controlled vocabulary.
Metadata records which describe a dataset that relates to one or more of the INSPIRE
themes must include the appropriate keyword(s) from the GEMET INSPIRE themes, as
illustrated in Example Two.
Examples Two and Three show how the GEMET INSPIRE themes and the GEMET concepts
controlled vocabularies should be cited according to the
INSPIRE guidance[9].
Note that more than one keyword value may be selected from a single controlled
vocabulary. Note also that keywords may be selected from more than one controlled
vocabulary. In this case the encoding shown in Example Three.
For INSPIRE if several keywords come from a single controlled vocabulary these shall
be grouped together.
For INSPIRE the use of a gmx:Anchor element is recommended over the use
gco:CharacterString for terms from controlled vocabularies
Recommended best practice is to select a human readable value from a controlled
vocabulary. An example from the Marine Geospatial community is
http://seadatanet.maris2.nl/v_bodc_vocab_v2/search.asp?lib=P02
Example
Example One (datasets/series) - without originating controlled vocabulary
Incorrect INSPIRE keywords -
Putting in more than one INSPIRE keyword, where the first keyword in the list is not
the correct Annex/Theme
Name : Temporal extent
UK GEMINI id
7
Definition
Date for the content of the data resource
Purpose and meaning
This is the date or date range that identifies the currency of the data. It may refer
to the period of collection, or the date at which it is deemed to be current.
Obligation
Mandatory for datasets and dataset series
Occurrence
Multiple
Data type
Date
Domain
Date, or two dates defining the duration of the period, as defined by BS ISO
8601.
Guidance
Dates may be to any degree of precision, from year (YYYY) to full date and
time.
The extended date format (YYYY-MM-DD) should be used, where YYYY is the year, MM the
month and DD the day.
If required, time (HH:MM:SS, where HH is the hour, MM the minute and SS the second)
may be added, with T separating the two parts.
Periods are recorded as {fromdate/todate} (e.g. 2006-04-01/2007-03-31). Either
fromdate or todate (but not both) may be left blank to indicate uncertainty.
There may be more than one Temporal Extent.
The coarsest resolution allowable is 'year'.
Comment
If the data resource relates to a historic period, then this is part of the subject,
e.g. 'cretaceous period'. In this case the date is the date of discovery or
observation.
This element should not be confused with Dataset reference date which is an
identifying date for the data resource.
Temporal extent is the date of the validity of the data and is different from
Dataset reference date which is an identifying date for the data resource.
For example, an atlas might represent data collected up to the end of one year, but
have a reference date of the following year.
The basic encoding for temporal extent is shown in Example One (datasets/series).
The temporal extent data shall be encoded using the gml:TimePeriod type from the gml
namespace. The underlying schemas and standards in fact allow greater flexibility
here
but for the purposes of GEMINI2 only the gml:TimePeriod XML element and the
gml:TimeInstant XML element (for single dates) shall be used. In addition
gml:TimePeriod shall contain only gml:beginPosition followed by gml:endPosition. Time
positions shall be expressed in the Gregorian calendar and UTC as per BS ISO
8601.
The gml:TimePeriod and gml:TimeInstant XML elements must have an identifier in order
to be schema valid. A UUID can be used, as is shown in the Example One
(datasets/series). The identifier only needs to be unique in the scope of the metadata
instance so a value of 't1' (see Example Two - datasets/series) is acceptable.
Allowable content of id attributes:
GML XML elements which are used in metadata have a mandatory gml:id attribute.
The value domain of the identifier is referred to as XML name. XML names have
certain restrictions. They may contain any alphanumeric character, non-English
alphanumeric characters, ideograms and the underscore, hyphen and period. They may
not contain any other punctuation characters. The colon is allowed, but its use is
reserved for namespaces, so it cannot appear in an identifier. XML names may not
include any whitespace including spaces and carriage returns. All names beginning
with the letters XML (in uppercase, lowercase or any mixture thereof) are
reserved.
XML names may only start with letters, ideograms and the underscore character.
Consequently, care must be taken when using the value of a UUID as the value of an
identifier because these can begin with numeric characters. It is normal to append
an underscore to the beginning of identifier values where they begin with
numbers.
Furthermore, an identifier must be unique within the scope of the XML document
(i.e. there shall not be more than one id type attribute with a particular
identifier value).
If an id type attribute contains an illegally formed XML name the result will be
a schema validation error.
For format of date and date-time values:
Dates and date-time shall be expressed in the Gregorian calendar and UTC as per
BS ISO 8601. The formatting shall be as follows, in order of increasing precision:
yyyy (e.g. 1995)
yyyy-MM (e.g. 1995-01)
yyyy-MM-dd (e.g. 1995-01-25)
yyyy-MM-ddThh:mm:ss (e.g. 1995-01-25T12:01:55)
The BS ISO 8601 encoding also allows negative dates to represent BC. However,
gco:Date and gco:DateTime XML elements do not accept negative values.
The GEMINI2 standard states that temporal extents may be given with as coarse a
granularity as century (e.g. yy or 19). However, unfortunately this cannot be
encoded in ISO 19139 XML and will result in a schema validation error. The lowest
level of granularity allowable is the year.
GEMINI2 allows for uncertainty in the temporal extent so that one or other, but not
both, begin position or end position may be blank. The corresponding encoding in this
case makes use of the indeterminatePosition attribute which may take a value of
'unknown' (Example Three for datasets/series). The indeterminatePosition
attribute may also take the following values:
'now': in which case the current date will be taken as the value the
now value must be used for an ongoing end position (INSPIRE)
'before': in which case the actual date is unknown but known to be
before the specified date
'after': in which case the actual date is unknown but known to be after
the specified date
Example Four shows encoding examples using these values.
Dataset reference date is an identifying date for the data resource. It is a notional
date of 'publication' of the data resource. It is different from Temporal extent
which is the actual date of the currency of the data. For example, an atlas might
have the
reference date '2007', but the data will have been collected over a period prior to
this.
Obligation
Mandatory
Occurrence
Multiple
Data type
Class
Domain
This class comprises two elements:
Date as defined by BS ISO 8601
Date type (publication/revision/creation).
The extended date format (YYYY-MM-DD) defined in BS ISO 8601 should be used, where
YYYY is the year, MM is the month and DD is the day. It may be extended to include
time
(HH:MM:SS), where HH is the hour, MM the minutes and SS the seconds, with the two
parts
separated by the character 'T'.
Date
Date Type
Definition
date used to reference data resource
event used to
describe reference date
Obligation
mandatory
mandatory
Occurrence
single
single
Data type
Date
CodeList
Domain
date as defined in ISO8601
Values
are:
creation
publication
revision
Guidance
Dates may be to any degree of precision, from year (YYYY) to full date and time. The
extended date format (YYYY-MM-DD) defined in BS ISO 8601 should be used, where YYYY
is
the year, MM the month and DD the day. It may be extended to include time (-HH:MM:SS,
where HH is the hour, MM the minute and SS the second), with 'T' separating
the two parts.
Identify whether date refers to creation, last revision or publication.
More than one Dataset Reference Date may be defined, but there must only be one of
type 'creation' and only one of type 'revision'
The date should be completed to a resolution sufficient to identify the version.
Thus if the data resource is updated annually, only a year is required, whilst if
it
is updated weekly, a day is required.
If the resource is continuously updated or is a dataset series (e.g. a map series),
then a notional current date should be provided at a suitable level of
resolution.
Comment
INSPIRE recommends that at least the date of the last revision should be reported
for spatial datasets
The encoding for dataset reference date is shown in Example One.
Dates may be expressed with low precision, as shown in the example. GEMINI2 also
allows the date and time to be published in metadata. In this case the date encoding
shown in Example Two must be used.
The format of date and date-time values is described at Dates and Times
Dataset reference date shall include a date type. The content of this XML element
is
drawn from a code list.
Example
Example One (datasets/series): dataset reference date encoding
example
Confusion of Date and DateTime In ISO 19115,
Date and DateTime are distinct types. Although in many elements, either is allowed,
the XML
encoding needs to be explicit about which is given. It is an error to put a date (such
as
2010-05-12) in a DateTime element. Example of invalid structure:
Information about the events or source data used in the construction of the data
resource
Purpose and meaning
The purpose of this element is to give an indication of how the data resource was
created. It is useful in determining its fitness for purpose.
Obligation
Mandatory
Occurrence
Single
Data type
CharacterString
Domain
Free text
Guidance
Some information should be provided. Include statements on the following:
source material
processes used to create the data, including resolution of measurement
method of updating
any quality control processes
Acronyms should be expanded to the full name along with the abbreviated version at
the beginning of the lineage. The abbreviated version can then be used.
Comment
This element is similar to Abstract, and some information may be included in either
element.
Further details included in an external file may be referenced under Additional information.
Examples
Addresses are taken from the Postcode Address File (PAF) and the property found on
the large-scale Ordnance Survey map. The coordinates of an approximate centroid for
the
property are recorded to a resolution of 1 metre. The dataset is updated from the
PAF
monthly updates. All results are checked by plotting a group of related addresses
on the
map and visually checking for errors.
The encoding for lineage is shown in the example below.
Note that, in addition to the lineage statement, the data quality scope shall be
encoded. For dataset metadata instances the MD_ScopeCode code list value shall be
'dataset'. For series metadata instances the code list value shall be
'series'.
For INSPIRE, the lineage statement must appear in the
gmd:dataQualityInfo/gmd:DQ_DataQuality element scoped to the entire described dataset
or series
Example
<gmd:MD_Metadata>
...
<gmd:dataQualityInfo>
<gmd:DQ_DataQuality>
<gmd:scope>
<gmd:DQ_Scope>
<gmd:level>
<gmd:MD_ScopeCode codeListValue='dataset'
codeList='https://schemas.isotc211.org/schemas/19139/resources/codelist/gmxCodelists.xml#MD_ScopeCode'>dataset</gmd:MD_ScopeCode>
</gmd:level>
</gmd:DQ_Scope>
</gmd:scope>
<gmd:lineage>
<gmd:LI_Lineage>
<gmd:statement>
<gco:CharacterString>The data shows polygonal and selected linear geological information, sourced from published
BGS 1:625 000 scale maps.</gco:CharacterString>
</gmd:statement>
</gmd:LI_Lineage>
</gmd:lineage>
</gmd:DQ_DataQuality>
</gmd:dataQualityInfo>
</gmd:MD_Metadata>
This element defines the geographical extent of coverage of the data resource
relative to an administrative hierarchy. It enables searches to be carried out to
find data
relevant to the area of interest. Extent polygons can be implied through reference
to an
external gazetteer. Note that Extent is the coverage of the data resource, not the
individual objects in the data resource. Thus if the data resource was national parks
in
England, the Extent would be 'England', even though many parts of England do not
have National Parks.
Obligation
Optional
Occurrence
Multiple
Data type
Class
Domain
The class comprises two elements:
(Optional) Authority code
Code identifying the extent
Guidance
An area approximating to the extent of coverage of the data resource should be
chosen. Where the extent does not coincide with any defined area or areas, then either
the nearest equivalent including the area of coverage, or a set of multiple areas
that
make up the coverage should be provided.
This should not be over-generalised (i.e. do not take it as Great Britain if it only
covers England and Wales).
Comment
Examples
England
East Anglia
The Wash
http://data.os.uk/id/7000000000041546 Central Scotland, using OS linked data as a
gazetteer
https://local-authority-eng.register.gov.uk/record/GLA, Greater London Authority,
using GDS "Local authorities in England" as a controlled list
http://vocab.nerc.ac.uk/collection/C64/current/5/, Irish Sea, in the NERC Vocabulary
"C64, United Kingdom Charting Progress 2 sea regions"
The examples shown below use codes (URIs in URL form) from the
Ordnance Survey Linked Data[22]boundary data. The
code element can be used as a URL returning a page on the internet providing further
information. The code in Example One, ending in 7000000000041546, is the URL for
Central Scotland. Associated with this code is further information, such as the
geometry of Central Scotland.
The entity responsible for managing the extent code can be expressed in GEMINI
metadata. An example of the encoding is shown in Example Two
Recommended best practice is to select a human readable value from a controlled
vocabulary. An example from the Marine Geospatial community is
http://seadatanet.maris2.nl/v_bodc_vocab_v2/search.asp?lib=C19
INSPIRE recommendations for encoding free text values which reference a specific
external resource or registry is to use gmx:Anchor instead of gco:CharacterString
Note that the extent XML element is in the gmd namespace
for datasets/series. This differs from service metadata instances where the extent
XML
element will be in the srv namespace.
The purpose of this element is to describe the vertical range of the data resource
(where relevant).
Obligation
Optional
Occurrence
Multiple
Data type
Class
Domain
EX_VerticalExtent, which comprises of three elements
minimum value
maximum value
coordinate reference
system
Definition
lowest vertical extent contained in the data
resource
highest vertical extent contained in the data resource
vertical coordinate reference system to which the maximum and minimum values are
measured
Obligation
mandatory
mandatory
mandatory
Occurrence
single
single
single
Data type
real
real
class
Domain
real number
real number
The class comprises two elements:
Authority code (optional)
Identifier of the coordinate reference system
Other comments
-
-
For example, code provided in the EPSG Geodetic Parameter Registry
Guidance
Minimum value: Identify approximate lowest vertical extent in the specified
coordinate reference system
Maximum value: Identify approximate highest vertical extent in the specified
coordinate reference system
Coordinate reference system: Identify coordinate reference system used for the
vertical extent measurements. This should be recorded as a name or as a code, for
example as provided in the EPSG Geodetic Parameter Registry produced by
The International Association of Oil & Gas Producers
(see http://www.epsg-registry.org/)
Comment
This element should be used only where vertical extent is significant, e.g. in geology,
mining, meteorology etc.
Examples
Minimum value: -100.0
Maximum value: 0.0
Coordinate reference system: height in metres above Newlyn Datum
GEMINI 1 to 2.0: made optional; occurrence changed from multiple to
single; description of class EX_VerticalExtent changed to match change to ISO
19115.
The encoding of the vertical extent information is explained. The vertical extent
information is expressed by a minimum and maximum coordinate value and a vertical
CRS.
The vertical CRS expresses the CRS of the vertical extent coordinates alone. It does
not necessarily express the vertical CRS to which vertical coordinates in the data
are
referenced - in other words it is possible that the vertical extent is defined in
a
different CRS from the vertical CRS of the data. This is convenient if it were the
case that datasets within a domain were referenced to many different vertical CRSs
because it could be decided that all vertical extents in metadata are to be referenced
to a single common vertical CRS to aid searching or understanding by users. Searching
by vertical extent, referenced to different vertical CRSs, across metadata sets would
be complicated by the need to undertake many coordinate operations - which is not
necessarily a trivial task - or even possible in all cases.
The CRS of vertical extent elements must be provided in order to give meaning to the
minimum and maximum coordinates. From the CRS, for example, it is possible to
determine the orientation of the coordinate system axis (i.e. do positive values
increase upwards or downwards from the zero reference) and the units of the coordinate
values.
There are two approaches to encoding the vertical CRS: by reference (Example One)
or
by value (Example Two). These examples express the same information: that the vertical
extent coordinates are referenced to Ordnance Datum (Newlyn). Codes and GML CRS data
are from the EPSG Registry.
Additionally, the gco:nilReason attribute can be used if the vertical CRS is unknown
(Example Three) but this renders the vertical extent information ambiguous at best.
Consequently it would be better to refrain from including vertical extent information
in the metadata instance altogether.
Example
Example One (datasets/series) - Vertical CRS by reference
Identifier, name or description of the system of spatial referencing, whether by
coordinates or geographic identifiers, used in the data resource
Purpose and meaning
The purpose of this element is to identify the way in which the data is spatially
referenced in the data resource. This may be by coordinates (e.g. the National Grid
of Great
Britain) or geographic identifiers (e.g. unit postcodes).
Obligation
At least one coordinate reference system shall be given
Occurrence
Multiple
Data type
Class
Domain
The class comprises two elements:
Code identifying the spatial reference system
(Conditional) codeSpace, - to be used if the code alone does not uniquely
identify the referred spatial reference system. - not to be used if the spatial
reference system is listed in the Default Coordinate Reference Systems
Guidance
For each spatial reference system
Identify the spatial reference systems used to spatially reference the data in
the data resource;
Check if the spatial reference system is listed in Annex D.4 (Default Coordinate
Reference Systems) of the INSPIRE Metadata Technical Guidelines
If the spatial reference system is not listed in the defaults, identify a well-known
register that defines the coordinate reference system or, if the spatial reference
system is using geographic identifiers (such as Post Codes, NUTS, what3words,
Geohashing), supply a resolveable HTTP-URI that provides more information about the
geographic identifier system.
Where there appears to be more than one spatial reference system used, take the one
that is used in resolving any conflict between the spatial referencing systems (e.g.
if the data is recorded referenced by unit postcodes, and a coordinate is then
associated, then unit postcode is the spatial reference system, whereas if the data
is
recorded by coordinate, and unit postcodes are added as an attribute, then it is
'National Grid of Great Britain').
Comment
Only coordinate reference systems identifiers specified in a well-known common
register shall be used
Note that the data resource may be supplied in a range of other reference systems
in
addition to that in which it is recorded.
When the provided text is a term or code from an externally defined explanation or
registry value, gmx:Anchor should be used instead of gco:CharacterString
The content of gmx:Anchor or gco:CharacterString must not be empty
Example
Example One - using gmx:Anchor for a default Coordinate Reference System (as defined
in Annex D.4 of the INSPIRE metadata technical guidance v.2)
Measure of the granularity of the data (in metres)
Purpose and meaning
The purpose of this element is to provide an indication of how detailed the spatial
data is. It is equivalent to the ground sample distance. It should not be confused
with the
scale of a map which is purely a display attribute (the spatial resolution should
be defined
in the specification of the data resource).
Obligation
Conditional - where a resolution distance can be specified
Occurrence
Multiple
Data type
Real
Domain
Value > 0
Guidance
For data capture in the field, it is the precision at which the data is
captured. This may be the accuracy for topographic surveys, or the average sampling
distance in an environmental survey.
For data taken from maps, it is the positional accuracy of the map (defined in the
specification of the map series).
For image data, it is the resolution of the image.
In many given cases, only approximate values can be given.
Comment
This should not be confused with precision which refers to the resolution of the
measurements themselves. Thus for a buildings dataset, a building seed could be recorded
to a precision of 0.1 metres, but since the requirement is for the seed only to be
within
the building footprint for the purpose of discriminating between buildings, the spatial
resolution of the buildings dataset would be the typical size of the building, i.e.
about
10 metres.
The encoding example for spatial resolution is shown in the example below.
A distance measurement shall be encoded and the unit of measurement shall be
identified. The unit of measurement is identified using the uom attribute of the XML
element gco:Distance. In the case of GEMINI2 all spatial resolution distance
measurements shall be in metres. The value of the uom attribute shall be:
urn:ogc:def:uom:EPSG::9001
This defines the unit of measure as metres by reference to the EPSG registry[12].
Location (address) for online access using a Uniform Resource Locator (URL)
address or similar addressing scheme
Purpose and meaning
The purpose of this element is to point to where the dataset, or
dataset series may be directly accessed online OR, if no direct access is available, to
an online resource providing more information about accessing the dataset or dataset
series.
Obligation
Conditional - Must be supplied when online access is available
Occurrence
Multiple
Data type
CharacterString
Domain
Valid URL
Guidance
Identify whether the resource may be accessed.
Determine the location of the resource (may be a URL).
The URL of a DOI landing page should be given as a Resource locator with a
CI_OnlineFunctionCode value of "information".
If no online access for the dataset or dataset series is available, but there is a
publicly available online resource providing additional information about how to access
the dataset of dataset series being described,
the URL pointing to this shall be given instead.
Although not mandatory, the following ISO 19115 sub-elements should be included, for
best results with data.gov.uk:
function (if provided, the gmd:CI_OnLineFunctionCode element should point to one of
the values
of the ISO 19139 code list CI_OnLineFunctionCode)
name (this appears on the data.gov.uk site)
description (data.gov.uk uses this if no 'name' provided)
Comment
The URL provided as the value of the gmd:linkage element should point to one of
following type of resources:
direct access for downloading the described dataset
a service metadata (capabilities) document of a Spatial Data Service used for
providing this dataset
a service WSDL document of a Spatial Data Service used for providing this data
set
a client application that directly accesses the described dataset
a web page with further instructions for accessing the described dataset
Examples
A DOI landing page: http://doi.org/10.5285/1e7d5e08-9e24-471b-ae37-49b477f695e3
The two examples illustrate different uses of Resource locator. Example one gives
direct access to the dataset.
Example two gives the location of further information about ordering the dataset.
ISO 19115 and the ISO
19139 encoding provides a means of indicating the function of the online resource
using the CI_OnLineFunctionCode code list.
Two values from this code list provide a
means of discriminating between a URL that is provided for information (code list
value of 'information') and a URL that is the address used for downloading
(code list value of 'download') the data.
The gmd:transferOptions XML element of gmd:MD_Distribution is used to encode a URL.
Note that it is necessary to encode distribution format information in all cases.
If
the URL that is provided is the location of a point of contact then the distribution
format is moot. However, the distribution format property is required by an ISO 19115
constraint. In this case the INSPIRE guidelines show the encoding using gmd:MD_Format.
Note that the element gmd:MD_Distribution must have the element gmd:distributionFormat
as its first child according to a constraint in ISO 19115. Format information may
not
always be known in which case the encoding of the element gmd:MD_Format shown in
Example One shall be used, following the
INSPIRE guidance[9]. If the format and version values
are known, then they should be given (see Data format).
Example
Example one, showing only required linkage content (for a dataset)
Defra metadata audit, October 2015: Very few records included direct links to WMS
end points.
Name : Data format
UK GEMINI id
21
Definition
Format in which the digital data is provided
Purpose and meaning
The purpose of this element is to identify the various options for data formats that
may be provided.
Obligation
Mandatory
Occurrence
Multiple
Data type
Class MD_Format from ISO 19115
Domain
The following properties are expected:
name of format
version of format (date, number etc)
Guidance
Entries should be recognised formats for data transfer, either standard or
proprietary.
Recommended best practice is to use a human readable term from a controlled
vocabulary.
If the data resource is not downloadable (e.g. is view only), then this should be
stated.
Comment
If the version of the data encoding is unknown or not versioned, a nil reason
attribute shall be specified with either "unknown" or "inapplicable" values used
correspondingly.
No Format provided - ISO 19139 requires that a format is given, either within the
'distribution' section or the 'distributor' section. INSPIRE & UK
GEMINI encoding guidance only expects the distribution section, as the place to encode
the
Resource locator, which effectively renders distribution format mandatory.
Name : Responsible organisation
UK GEMINI id
23
Definition
Details of the organisation(s) responsible for the establishment, management,
maintenance and distribution of the data resource
Purpose and meaning
This informs the user about who is responsible for the data resource
Obligation
Mandatory
Occurrence
Multiple
Data type
Class
Domain
This class comprises eight elements relating to the responsible organisation:
Metadata element
name
Definition
Obligation
Occurrence
Data
type
Domain
Rules for how to fill in the entry
contact position
role or position of the responsible
person
optional
single
CharacterString
free
text
A general job title or generic role should be identified for someone in a position
of responsibility for the data resource. Do not identify an individual by name,
as this is subject to change without warning and the information is impossible to
keep up-to-date.
organisation name
name of
organisation
mandatory
single
CharacterString
free
text
The name of the organisation should be given in full, without
abbreviations
postal address
postal address of the
organisation
optional
single
CharacterString
free
text
The full formal postal address (as defined for example by Royal Mail) should be
given, including the postcode.
telephone number
telephone number by which individuals can talk to the
organisation or
individual
optional
single
CharacterString
free
text
The full telephone number should be given.
email address
internet email address which individuals can use to
contact the organisation or
individual
mandatory
single
CharacterString
free
text
A valid email address should be given. Do not provide a personal email
address.
The role of the responsible party should be identified. For
datasets and dataset series, at least a distributor should be given.
Guidance
The organisation name, email address and responsible party role are mandatory. Other
entries should only be given that are relevant and known.
Where no single individual is responsible, a generic role may be given.
Where there are multiple Distributors / Responsible Organisations, then a separate
entry should be given for each.
For dataset and dataset series, one of the Responsible Organisations must be in the
role of Distributor (If there is only one Responsible Organisation recorded, then
it
must be in the role of Distributor.).
Where there are several distributors, a separate entry should be given for
each.
For best result with data.gov.uk:
Enter 'Owner' for UK Location Data Provider role.
Enter 'Publisher' For UK Location Data Publisher role.
These appear in the data.gov.uk search results.
If the data was created by someone other than the Data Provider, this should also
be
recorded, using the role value 'Originator'.
Comment
Facsimile number is no longer required
Examples
See individual elements below.
Metadata element name
Purpose and Meaning
Examples
contact position
Role or post of the person to contact in the organisation
The mapping product manager
organisation name
Ordnance Survey, Great Britain
postal address
Adanac Drive, Southampton, United Kingdom, SO16 0AS
GEMINI 1 to 2.0: This has been generalised from Distributor (and Originator)
to cover a range of possible roles, by the addition of 'responsible party role' and
minor errors in the class details have been corrected.
At least one limitation on public access shall give an INSPIRE reason
Comment
Limitations on public access are different from Use constraints which are warnings
about its suitability for particular types of usage, or constraints on the use that
can be made of the data.
Missing or incorrect information
Licence information should be provided, preferably by a URL.
It is an error to state 'no limitations' in Limitations on Public Access, when the
resource is
not open access.
Defra metadata audit, October 2015: In many cases either this field has been left
empty or where the PSMA (or similar) licensing arrangements are referenced there is
either a
lack of detail or no links to the appropriate sites.
Name : Use constraints
UK GEMINI id
26
Definition
Restrictions and legal restraints on using the data resource
Purpose and meaning
The purpose of this element is to describe any restrictions on usage of the data (as
opposed to access)
Obligation
Mandatory
Occurrence
Multiple
Data type
CharacterString
Domain
Free text
Guidance
Provide information on any constraints to using the resource, e.g. licensing, fees,
usage restrictions, or refer to a URL where this information is available, e.g. a
licence document. If entering a URL, enter this as a sub-element, not as part of free
text. Where relevant, Data Provider licence information should be provided in the
form of a Licence Title,
and where possible, a licence URL. If more than one type of licence is included
then the URL should point to a Data Providers page.
Any known constraints should be identified. If no conditions apply, then 'no
conditions apply' should be recorded.
Comment
Use constraints are different from Restrictions on public access which describe
limitations on access to the data. A data resource can have open access (e.g. to look
at
it), but restricted use.
This element shall be encoded in a different resourceConstraints/MD_LegalConstraints
XML element to GEMINI element 25 Limitations on public access
The MD_LegalConstraints element shall contain a useConstraints element
Note: INSPIRE allows an accessConstraints element here; GEMINI recommends using Limitations
on public access for these
The useConstraints element shall contain an MD_RestrictionCode element with code list
value "otherRestrictions"
The LegalConstraints element shall also contain a gmd:otherConstraints element, with
free text.
"No conditions" and "conditions unknown" shall be specified using a gmx:Anchor link
to the relevant entry in the INSPIRE metadata registry, http://inspire.ec.europa.eu/metadata-codelist/ConditionsApplyingToAccessAndUse
In certain circumstances it might be appropriate to refer to an external document
describing constraints. In this case the encoding shown in Example Two may be used.
This is recommended for licenses, even the use of ISO 19115 otherRestrictions would
not generally include license restrictions, as they have their own term in the ISO
19115 code list.
If there are no limitations the value of gmd:otherConstraints shall be 'no limitations'
(see Example Three).
There may be more than one gmd:otherConstraints element
Example
Example One
<gmd:MD_Metadata>
...
<gmd:identificationInfo>
<gmd:MD_DataIdentification id="bgs-0000-1">
...
<gmd:resourceConstraints>
<gmd:MD_LegalConstraints>
<gmd:useConstraints>
<gmd:MD_RestrictionCode
codeList='https://schemas.isotc211.org/schemas/19139/resources/codelist/gmxCodelists.xml#MD_RestrictionCode'
codeListValue='otherRestrictions'>otherRestrictions</gmd:MD_RestrictionCode>
</gmd:useConstraints>
<gmd:otherConstraints>
<gco:CharacterString>Not to be used for navigation</gco:CharacterString>
</gmd:otherConstraints>
...
</gmd:MD_LegalConstraints>
</gmd:resourceConstraints>
...
</gmd:MD_DataIdentification>
</gmd:identificationInfo>
...
</gmd:MD_Metadata>
Missing or incorrect constraints information Licence information should be provided, preferably by a URL.
It is an error to state 'no conditions apply' in Use Constraints, when restrictions
do in fact exist.
Name : Additional information
UK GEMINI id
27
Definition
Other descriptive information about the data resource
Purpose and meaning
The purpose of this element is to record relevant information that does not clearly
belong in another element.
This may be a reference (e.g. a URL).
Obligation
Optional
Occurrence
Single
Data type
CharacterString
Domain
Free text
Guidance
Information about access to the resource should be in Resource locator.
<gmd:MD_Metadata>
...
<gmd:identificationInfo>
<gmd:MD_DataIdentification id="BGS-625-001">
...
<gmd:supplementalInformation>
<gco:CharacterString>Ongoing modifications to dataset as appropriate. UK coverage except for western and southern margin
of Northern Ireland. As accurate as the underlying geological interpretation. 1:625k scale resolution. Bedrock theme
numerically coded. Superficial theme lex-rock coded.
</gco:CharacterString>
</gmd:supplementalInformation>
</gmd:MD_DataIdentification>
</gmd:identificationInfo>
...
</gmd:MD_Metadata>
The purpose of this is to uniquely identify the data resource.
Obligation
Mandatory for datasets and dataset series
Occurrence
Multiple
Data type
Class
Domain
The class comprises the following elements:
Code - Identifier code or name, often from a controlled list or pattern defined by
a
code space.
Codespace - Identifier of a code space within which one or more codes are
defined.
These elements are described in the table below
Metadata element name
code
codeSpace
Definition
Identifier code or name, often from a controlled list or pattern defined by a code
pace
Identifier of a code space within which one or more codes are defined
Obligation
mandatory
conditional ~ must be suppled if the code by itself does not uniquely identify the
resource.
Occurrence
single
single
Data type
CharacterString
CharacterString
Domain
free text
free text
Other comments
-
This code space is often defined by some
authority organization, were one organization may define multiple code spaces. The
range and format of each code space identifier is defined by that code space
authority.
Guidance
The code is generally assigned by some authority, with a codespace uniquely
identifying the context of the identifier code.
The codespace must be a character string that uniquely identifies the namespace for
the identifier code. This should be the internet domain of the data owner/provider,
e.g.: data.bgs.ac.uk/id/dataHolding/
The resource is identified by a unique identifier code, generally assigned by the
data owner. A character string namespace uniquely identifying the context of the
identifier code may be added for uniqueness. This is usually allocated by an
appropriate authority such as the manager of the spatial data infrastructure.
Where present, a DOI should be recorded as a resource identifier, with the codespace
being doi. If a DOI landing page is also available, then include this using an Anchor.
Comment
Since INSPIRE metadata technical guidance version 2, it is no longer required to use
RS_Identifier if a value for code space value is provided. In such cases
(where there is a code space provided) it is now strongly recommended to use
MD_Identifier and encode the complete URI in the code element.
The resource identifier can be a globally unique identifier such as a UUID, in which
case it is encoded as shown in Example One.
The form used in Example One can also be used if the identifier is expressed as a
code space and code in URI form like http://image2000.jrc.it#image2000_1_nl2_multi
However a better way to do this is to use the gmx:Anchor as in Example Two.
Note that the identifier is encoded in the citation of the metadata instance
A resource identifier (which may be the same as the code) should also be added to
the 'id' attribute of the gmd:MD_DataIdentification type. This follows the
examples in the
INSPIRE guidance[9].
Care must be taken with the value of the id attribute code. The attribute
'id' has the data type xs:ID which must have as its value an XML name. This
means that it cannot start with a number, and has a restricted set of characters it
can include. This means that normally it cannot be an UUID or an URI. The id must
also
be unique across all id attributes in the metadata document
Statement of conformity with the product specification or user requirement against
which the data is being evaluated
Purpose and meaning
The purpose of this is to record the conformity to the INSPIRE or other data
specification
Obligation
Mandatory
Occurrence
Multiple
Data type
Class
Domain
This class comprises the following elements:
Specification
Degree
Explanation
For details see below.
Metadata element name
specification
degree
explanation
Definition
Citation of the product specification or user requirement
against which data resource is evaluated
degree of conformity with the
specification
meaning of conformance for this result
Meaning
The purpose of this element is to identify the specification
against which conformity is evaluated
The purpose of this element is to
identify the conformity of the data resource to the cited specification
The
purpose of this element is to explain the meaning of conformity in this
context
Obligation
Mandatory
Mandatory
Mandatory
Occurrence
single
single
single
Data type
Class CI_Citation (from
ISO19115)
Boolean
CharacterString
Domain
The following properties are expected:
title of type character string (free text)
reference date defined as
a date type (creation, revision, or publication)
an effective date
true if conformant false if not conformant
free
text
Rules
Cite the specification to which the data resource should
conform
The data resource should be evaluated against the specification and
the result recorded
Include a statement about which aspects of the
specification the data resource conforms and any exceptions
Examples
D2.8.I.5 INSPIRE Data Specification on Addresses - Guidelines,
publication, 2010-04-26
true
Only mandatory items included
Guidance
At least one conformity statement shall be to an INSPIRE specification, even if simply
to say that the data set is not conformant or not tested
Other conformity statements may be added, citing INSPIRE technical guidance or other
specifications
Each conformity statement shall relate to only one specification
Assess the conformity of the data resource against its product specification or the
INSPIRE thematic data specification.
State the data specification to which the degree of conformity applied and optionally
an 'Explanation',
for example to reference the conformance criteria in the specification against which
conformance is being claimed.
For INSPIRE, Datasets and dataset series shall declare conformity to [Regulation 1089/2010].
Comment
The specification is identified in the element Specification.
The conformance of a data resource may be considered with respect to more than one
specification.
For INSPIRE, the citation title shall be the official title of the INSPIRE
Implementing Rule, specification document or Conformance Class
For INSPIRE, the date given will be the date of publication of the INSPIRE
Implementing Rule, specification document or Conformance Class
For INSPIRE Implementing Rule documents, the value of the title element shall match
exactly the official title of the cited document in the language of the metadata.
Examples
Conformance of a dataset to Regulation 1089/2010 would have the title:
Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive
2007/2/EC of the European Parliament and of the Council as regards interoperability
of
spatial data sets and services., and would give a publication date of
2010-12-08
The encoding for Conformity is shown in the example.
Note that the encoding of conformity requires a specification (encoded using
gmd:CI_Citation), an explanation and a pass.
INSPIRE Metadata Implementing Rules state that there are three possible conformance
results: conformant, not conformant and not
evaluated. Not evaluated is expressed by a conformity statement with a nilReason
(unknown) specified in the pass element.
All gmd:dataQualityInfo XML element shall have a gmd:scope
XML element, set to 'dataset' or 'series' as appropriate.
Example of a conformity report for Implementing Rule 1089/2010, where conformance
is not evaluated.
Example follows updated guidance to use gmx:Anchor over gco:CharacterString for Citation
titles
<gmd:report
xmlns:gmd="http://www.isotc211.org/2005/gmd"
xmlns:gco="http://www.isotc211.org/2005/gco"
xmlns:gmx="http://www.isotc211.org/2005/gmx"
xmlns:xlink="http://www.w3.org/1999/xlink">
<gmd:DQ_DomainConsistency>
<gmd:result>
<gmd:DQ_ConformanceResult>
<gmd:specification>
<gmd:CI_Citation>
<gmd:title>
<gmx:Anchor xlink:href="http://data.europa.eu/eli/reg/2010/1089">
Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive
2007/2/EC of the European Parliament and of the Council as regards interoperability
of spatial data sets and services</gmx:Anchor>
</gmd:title>
<gmd:date>
<gmd:CI_Date>
<gmd:date>
<gco:Date>2010-12-08</gco:Date>
</gmd:date>
<gmd:dateType>
<gmd:CI_DateTypeCode
codeList='https://schemas.isotc211.org/schemas/19139/resources/codelist/gmxCodelists.xml#CI_DateTypeCode'
codeListValue='publication' />
</gmd:dateType>
</gmd:CI_Date>
</gmd:date>
</gmd:CI_Citation>
</gmd:specification>
<!-- Explanation is a required element but can be empty -->
<gmd:explanation gco:nilReason="inapplicable"/>
<!-- Conformance has not been evaluated -->
<gmd:pass gco:nilReason="unknown" />
</gmd:DQ_ConformanceResult>
</gmd:result>
</gmd:DQ_DomainConsistency>
</gmd:report>
Example three ~ Topological consistency, showing mandatory elements for a descriptive
topological consistency report
<gmd:report>
<gmd:DQ_TopologicalConsistency>
<gmd:result>
<gmd:DQ_ConformanceResult>
<gmd:specification>
<gmd:CI_Citation>
<gmd:title>
<!-- The title for this report shall always be "INSPIRE Data Specifications - Base Models - Generic Network Model" -->
<gco:CharacterString>INSPIRE Data Specifications - Base Models - Generic Network Model</gco:CharacterString>
</gmd:title>
<gmd:date>
<gmd:CI_Date>
<gmd:date>
<!-- The date shall be the date of publication of the Generic Network Model -->
<gco:Date>2013-04-05</gco:Date>
</gmd:date>
<gmd:dateType>
<!-- The code list value shall always be publication -->
<gmd:CI_DateTypeCode codeList='https://schemas.isotc211.org/schemas/19139/resources/codelist/gmxCodelists.xml'
codeListValue='publication'/>
</gmd:dateType>
</gmd:CI_Date>
</gmd:date>
</gmd:CI_Citation>
</gmd:specification>
<!-- An explanation must be provided -->
<gmd:explanation><gco:CharacterString>[Some statement on topological consistency]</gco:CharacterString></gmd:explanation>
<gmd:pass>
<!-- The value shall always be false to indicate that the data does not assure the centerline topology for the network -->
<gco:Boolean>false</gco:Boolean>
</gmd:pass>
</gmd:DQ_ConformanceResult>
</gmd:result>
</gmd:DQ_TopologicalConsistency>
</gmd:report>
Conformity statement missing
INSPIRE requires a 'conformity' statement, which can say that the resource conforms,
or does not
conform to a specification, or that it hasn't been tested. This is encoded with an ISO 19139 quality report. Incorrect citation of INSPIRE regulation
When citing the INSPIRE regulation, the title and publication date need to match exactly.
Any deviation may result in the validation failure message "The gmd:pass element is
not nillable and shall have a value" - even if the error is in the spelling of the
title.
Name : Equivalent scale
UK GEMINI id
43
Definition
Level of detail expressed as the scale denominator of a comparable hardcopy map or
chart
Purpose and meaning
This is purely to conform to INSPIRE, and has little meaning for most digital
data
Obligation
Optional
Occurrence
Multiple
Data type
Integer
Domain
Positive integer
Guidance
Where the data is captured from a map, the scale of that map should be
recorded.
Comment
Expression of spatial resolution by distance is preferred. Spatial resolution
should only be expressed by equivalent scale where a distance cannot be
determined.
Rectangle enclosing the extent of the data resource described in latitude and
longitude
Purpose and meaning
This is to enable the resource to be located geographically
Obligation
Mandatory
Occurrence
Multiple
Data type
Class
Domain
EX_GeographicBoundingBox
Metadata element name
West bounding longitude
East bounding
longitude
South bounding latitude
North bounding latitude
Definition
western-most limit of the data resource extent, expressed in
longitude in decimal degrees (positive east)
eastern-most limit of the data
resource extent, expressed in longitude in decimal degrees (positive
east)
southern-most limit of the data resource extent, expressed in latitude
in decimal degrees (positive north)
northern-most limit of the data resource extent,
expressed in latitude in decimal degrees (positive north)
Obligation
mandatory
mandatory
mandatory
mandatory
Occurrence
single
single
single
single
Data type
Decimal, expressed in degrees to at least two decimal
places
Domain
-180.00 <= west bounding longitude <= 180.00
-180.00 <= east bounding longitude <= 180.00
-90.00 <= south bounding latitude <= north bounding
latitude
south bounding latitude <= north bounding latitude <= 90.00
Other comments
The West bounding coordinate usually has a value less
than the value of the East bounding coordinate, except when the extent straddles the
180 degree meridian.
The East bounding longitude usually has a value greater
than the value of the West bounding longitude, except when the extent straddles the
180 degree meridian.
Guidance
Identify a bounding box slightly larger than the extent of the data resource, and
determine the coordinates of the boundaries. It may be necessary to convert from another
coordinate system (e.g. National Grid) into lat/long.
Only approximate values are required, sufficient to identify the extent on a global
basis. The bounding box is implicitly in WGS84.
Comment
The bounding box will often cover areas that are not directly related to the area
covered by the resource.
The encoding example for geographic bounding box for datasets is shown in the
example
Note that the extent XML element is in the gmd namespace. This differs from service
metadata instances where the extent XML element will be in the srv namespace.
The definition of the equivalent ISO 19115 class, EX_GeographicBoundingBox, is
'Geographic area of the entire dataset referenced to WGS 84'. Consequently,
the CRS of the coordinates expressed in metadata is always WGS 84 (identified by the
EPSG URI http://www.opengis.net/def/crs/EPSG/0/4326). This means that the coordinate
values shall be expressed in units of degrees (encoded using decimal numbers) with
axes orientated north and east. The geodetic datum is WGS 84.
Overly precise bounding box GEMINI states that the bounding latitude and longitude should be stated to at least
two
decimal places. The INSPIRE geoportal used to report two decimal places as an error;
it does
not now. However, some software defaults to values that are unnecessarily "precise".
For example:
Six decimal places of a degree is something like 1cm, so the longitude above is being
given
to roughly the nearest molecule.
Name : Quality scope
UK GEMINI id
48
Definition
The specific data to which the data quality information applies
Purpose and meaning
To enable data quality to be reported on a subset of the data resource
Obligation
Mandatory
Occurrence
Multiple
Data type
Class
Domain
DQ_Scope from ISO 19115
Guidance
For the conformity statement and lineage of metadata describing:
a dataset, set quality scope to 'dataset'
a dataset series, set quality scope 'series'
If using a Data Quality element to describe something other than the whole dataset
or series,
then provide additional DQ_DataQuality elements with their Scope set appropriately
Comment
Required in the ISO 19115 encoding of GEMINI 2 metadata records, to assist in
managing related metadata records.
All gmd:dataQualityInfo XML element shall have a gmd:scope XML element, set to as
appropriate.
There shall be exactly one gmd:dataQualityInfo/gmd:DQ_DataQuality element scoped to
the entire described data set or data set series.
This shall contain the Conformity and Lineage elements, and any Quality measures that
relate to the the entire dataset or series
Other quality measures, e.g. for specific feature types, shall be separate DQ_DataQuality
elements, with the relevant Quality scope.
In these cases the Level Description must also be set
The method used to spatially represent geographic information
Purpose and meaning
The type in which the spatial data is represented may be of importance when
evaluating the fit for purpose of the dataset. The code list value of this element
is
intended for describing this information.
Obligation
Mandatory
Occurrence
Multiple
Data type
Class (CodeList)
Domain
MD_SpatialRepresentationTypeCode from ISO 19115. Codes to be used are:
vector
grid
tin
textTable
Guidance
tin stands for triangulated irregular network. TIN is a digital data structure used
in a geographic information system (GIS) for the representation of a surface
textTable should be used for datasets with an indirect spatial reference
grid should be used for images and coverage data
Comment
This element is regarded by the INSPIRE metadata technical guidance as
interoperability metadata for datasets and dataset series
To allow quantitative description of the completeness, consistency, accuracy, and
correctness of the data
Obligation
Conditional: Topological consistency report is mandatory if the dataset includes types
from the INSPIRE Generic
Network Model and does not assure centerline topology (connectivity of centrelines)
for
the network, otherwise optional
Occurrence
Multiple
Data type
Class, subtypes of DQ_Element
Domain
DQ_Element from ISO 19115
DQ_Element is an abstract complex type and has to be expressed by a corresponding
DQ_xxx subelement concerning the particular data quality issue
e.g. DQ_ConceptualConsistency. All these types have the same sub-attributes, such
as nameOfMeasure, dateTime, result.
It is important to choose the correct subelement, to clearly indicate the type of
quality statement being made.
Only the result sub-element (value, value type) is mandatory.
All DQ_Element subtypes have the same sub-elements.
Table 1 Data Quality sub-elements
Data Quality sub-element name
result
dateTime
nameOfMeasure
Definition
value (or set of values) obtained from applying a data quality measure or the outcome
of evaluating the obtained value (or set of values) against a specified acceptable
conformance quality level
date or range of dates on which a data quality measure was applied
name of the test applied to the data
Obligation
mandatory
optional
optional
Occurence
single
single
single
Data type
DQ_QuantitativeResult
DateTime
CharacterString
Domain
see table two below
see table three below
Table 2: DQ_QuantitativeResult
Data Quantitative Result sub-element name
valueUnit
value
valueType
Definition
the units in which the result is reported
the quantitative result
the data type of the result
Obligation
mandatory
mandatory
mandatory
Occurence
single
multiple
single
Data type
UnitOfMeasure
Record
RecordType
Domain
see table three below
see table three below
Table 3: Details for various types of quality measure
See the relevant specification for more details of each measure
Completeness - Commission
DQ_CompletenessCommission
excess data present in the dataset, as described by the scope
Rate of excess items
Real
AU, AD, TN, HY, PS, EL, LC, SU, BU, LU, US
Number of duplicate feature instances
Integer
TN
Completeness - Omission
DQ_CompletenessOmission
data absent from the dataset, as described by the scope
Rate of missing items
Real
GN, AU, AD, CP, TN, HY, PS, EL, LC, OI, (not GE), SU, BY, SO, LU, US, PF, AF, OF
Conceptual consistency
DQ_ConceptualConsistency
adherence to rules of the conceptual schema
Non-compliance rate with respect to the rules of the conceptual schema
Real
EL
Number of items not compliant with the rules of the conceptual schema
Integer
AU, TN
Conceptual schema non-compliance
Boolean
LC
Domain consistency
DQ_DomainConsistency
adherence of values to the value domains
Number of items not in conformance with their value domain
Integer
AU
Value domain non-conformance rate
Real
EL
Value domain conformance rate
Real
HY
Value domain non-conformance
Boolean
LC
Topological consistency
DQ_TopologicalConsistency
Correctness of the explicitly encoded topological characteristics of the dataset
Note: Only use this if the topological consistency can be quantified,
otherwise provide a descriptive result with a DQ_ConformanceResult element; see GEMINI
Conformity element
Number of faulty point-curve connections
Integer
AU, TN, HY
Number of missing connections due to undershoots
Integer
AU, TN, HY
Rate of missing connections due to undershoots
Real
EL
Number of missing connections due to overshoots
Integer
TN, HY
Rate of missing connections due to overshoots
Real
EL
Number of missing connections due to crossing of bridge/road
Integer
HY
Number of invalid overlaps of surfaces
Integer
HY
Slivers
Integer
SU
Number of invalid slivers
Integer
Number of invalid self-intersect errors
Integer
TN, HY, LC
Rate of invalid self-intersect errors
Real
EL
Number of invalid self-overlap errors
Integer
TN, HY
Rate of invalid self-overlap errors
Rate
EL
Number of watercourse links below threshold length
Integer
HY
Number of closed watercourse links
Integer
HY
Number of multi-part watercourse links
Integer
HY
Format consistency
DQ_FormatConsistency
Degree to which data is stored in accordance with the physical structure of the dataset
Physical structure conflict rate
EL
Physical structure conflicts
Boolean
LC
Absolute or external accuracy
DQ_AbsoluteExternalPositionalAccuracy
closeness of reported coordinate values to values accepted as or being true
Mean value of positional uncertainties
Measure
Positional accuracy
Measure
SU
Root mean square error of planimetry
Measure
EL, LC
Root mean square error
Measure
EL
Gridded positional accuracy
DQ_GriddedDataPositionalAccuracy
Closeness of gridded data position values to values accepted as or being true
Root mean square error of planimetry
Measure
EL
Relative positional accuracy
DQ_RelativeInternalPositionalAccuracy
closeness of the relative positions of features in the scope
to their respective relative positions accepted as or being true
Relative horizontal error
Measure
Root mean square error of planimetry
Real
LC
Temporal validity
DQ_TemporalValidity
Temporal accuracy
Boolean
SU
Thematic accuracy - classification
DQ_ThematicClassificationCorrectness
Comparison of the classes assigned to features or their attributes to a universe of
discourse
Misclassification rate
Real
TN, LC
Thematic accuracy
Real
SU
Misclassification matrix
Matrix of integers
LC
Quantitative attribute accuracy
DQ_QuantitativeAttributeAccuracy
Accuracy of quantitative attributes
Attribute value uncertainty at 95% significance level
Real
HY
Scatter plot
Graphical
LC
non-quantitative attribute correctness
DQ_NonQuantitiveAttributeAccuracy
correctness of non-quantitative attributes
Rate of incorrect attribute values
Real
Number of incorrect attribute values
Integer
Other attributes of ISO 19115 DQ_Element may be included, e.g.:
Table 4 Optional data quality sub-elements
evaluationMethodType
evaluationMethodDescription
Definition
type of method used to evaluate quality of the dataset
description of the evaluation method
Obligation
optional
optional
Occurence
single
single
Data type
DQ_EvaluationMethodTypeCode
free text
Domain
directInternal
method of evaluating the quality of a dataset based on inspection of items within
the dataset, where all data required is internal to the dataset being evaluated
directExternal
method of evaluating the quality of a dataset based on inspection of items within
the dataset, where reference data external to the dataset being evaluated is required
indirect
method of evaluating the quality of a dataset based on external knowledge
For example, in the
INSPIRE Metadata Technical Guidelines, recommendation 2.3 says “It is recommended
to provide a short description of the evaluation method used for topological consistency
check”.
Guidance
Comment
This element is regarded by the INSPIRE metadata technical guidance as
interoperability metadata for datasets and dataset series
Topological consistency either:
metadata/2.0/req/isdss/topological-consistency-quantitative-results or:
metadata/2.0/req/isdss/topological-consistency-descriptive-results
Other types are specified in the data specifications
There shall be exactly one gmd:dataQualityInfo/gmd:DQ_DataQuality element scoped to
the entire described data set or data set series.
So if the scope of the quality measure is the entire dataset or series, then the result
shall be in the same DQ_DataQuality element as the Conformity and Lineage elements
Other quality measures, e.g. for specific feature types, shall be separate DQ_DataQuality
elements, with the relevant Quality scope
Quantitative results shall be reported using the relevant gmd:report/gmd:DQ_XXXXX
element with a gmd:DQ_QuantitativeResult element as the value of its mandatory gmd:result
property.
The gmd:valueUnit and gmd:value/gco:Record child elements of gmd:DQ_QuantitativeResult
shall be used for giving a numerical or otherwise quantitative value.
The value type of the result shall be declared using the xsi:type attribute of the
gco:Record element. Note that many of the INSPIRE Data Specifications give a value
type of “Real, percentage, ratio”; GEMINI recommends using real numbers in all these
cases, which should be declared as xs:double.
As well as the mandatory elements, it is also recommended to supply a name of
the measure, a short description of the evaluation method, and a date for the evaluation
of the consistency check
Information about the scope and frequency of updating
Purpose and meaning
Obligation
Optional
Occurrence
Single
Data type
MD_MaintenanceInformation
Domain
ISO 19115 MD_MaintenanceInformation
At least maintenanceAndUpdateFrequency should be used, in addition it is
recommended to supply updateScope/MD_ScopeCode and maintenanceNote, but only one of
each
Table 1 Maintenance information sub-elements
Sub element name
maintenance and update frequency
update scope
maintenance note
Definition
frequency with which changes and
additions are made to the resource
after the initial resource is
completed
scope of data to which
maintenance is applied
information regarding specific
requirements for maintaining the
resource
Obligation
Mandatory
Optional
Optional
Occurence
single
single
single
Domain
Maintenance frequency code (ISO 19115)
Scope code (ISO 19115)
free text
Maintenance frequency code has values such as continual, weekly, monthly, annually, notPlanned, unknown
Scope code has values such as dataset, series, feature, tile
Guidance
Comment
Recommended for all INSPIRE themes See the relevant INSPIRE data
specifications, section 8.3.1 for further theme specific information
<gmd:resourceMaintenance>
<gmd:MD_MaintenanceInformation>
<!-- At least maintenanceAndUpdateFrequency should be used -->
<gmd:maintenanceAndUpdateFrequency>
<gmd:MD_MaintenanceFrequencyCode
codeList='https://schemas.isotc211.org/schemas/19139/resources/codelist/gmxCodelists.xml#MD_MaintenanceFrequencyCode'
codeListValue='annually'>annually</gmd:MD_MaintenanceFrequencyCode>
</gmd:maintenanceAndUpdateFrequency>
<!-- The following elements are recommended-->
<gmd:updateScope>
<gmd:MD_ScopeCode codeListValue='dataset'
codeList='https://schemas.isotc211.org/schemas/19139/resources/codelist/gmxCodelists.xml#MD_ScopeCode'>dataset</gmd:MD_ScopeCode>
</gmd:updateScope>
<gmd:maintenanceNote>
<gco:CharacterString>[Information regarding specific requirements for maintaining the resource]</gco:CharacterString>
</gmd:maintenanceNote>
</gmd:MD_MaintenanceInformation>
</gmd:resourceMaintenance>
