Help:List of datatypes
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Using different datatypes, properties can be used to describe very different kinds of values. A complete list of all 16 datatypes provided by Semantic MediaWiki and 1 provided by other semantic extensions is available from special page "Types". The available datatypes are:
| Datatype | Description | ID | Help page | Provided by |
|---|---|---|---|---|
| Annotation URI | Holds URIs, but has some technical differences during export compared to the "URL" type | _anu | Help:Datatype "Annotation URI" | Semantic MediaWiki |
| Boolean | Holds boolean (true/false) values | _boo | Help:Datatype "Boolean" | Semantic MediaWiki |
| Code | Holds technical, pre-formatted texts (similar to type Text) | _cod | Help:Datatype "Code" | Semantic MediaWiki |
| Date | Holds particular points in time | _dat | Help:Datatype "Date" | Semantic MediaWiki |
| Holds e-mail addresses | _ema | Help:Datatype "Email" | Semantic MediaWiki | |
| External identifier | Holds a value that associates it with with a external URI for formatting | _eid | Help:Datatype "External identifier" | Semantic MediaWiki |
| Geographic coordinate | Holds coordinates describing geographic locations | _geo | Help:Datatype "Geographic coordinate" | Maps (Semantic Maps) |
| Monolingual text | Holds a text value that associates the annotation with a specific language code | _mlt_rec | Help:Datatype "Monolingual text" | Semantic MediaWiki |
| Number | Holds integer and decimal numbers, with an optional exponent | _num | Help:Datatype "Number" | Semantic MediaWiki |
| Page | Holds names of wiki pages, and displays them as a link | _wpg | Help:Datatype "Page" | Semantic MediaWiki |
| Quantity | Holds values that describe quantities, containing both a number and a unit | _qty | Help:Datatype "Quantity" | Semantic MediaWiki |
| Record | Holds compound property values that consist of a short list of values with fixed type and order | _rec | Help:Datatype "Record" | Semantic MediaWiki |
| Telephone number | Holds international telephone numbers based on the RFC 3966 standard | _tel | Help:Datatype "Telephone number" | Semantic MediaWiki |
| Temperature | Holds temperature values (similar to type Quantity) | _tem | Help:Datatype "Temperature" | Semantic MediaWiki |
| Text | Holds text of arbitrary length | _txt | Help:Datatype "Text" | Semantic MediaWiki |
| Reference | Holds a value that associates it to individual defined provenance metadata record | _ref_rec | Help:Datatype "Reference" | Semantic MediaWiki |
| URL | Holds URIs, URNs and URLs | _uri | Help:Datatype "URL" | Semantic MediaWiki |
Example values and formatting
| Datatype | Property | Example value | Query display | Query display using #- (plain) |
|---|---|---|---|---|
| Annotation URI | Property:Has annotation uri | http://www.semantic-mediawiki.org | http://www.semantic-mediawiki.org | http://www.semantic-mediawiki.org |
| Boolean | Property:Has boolean | true | true | true |
| Code | Property:Has code | Code
is preserved but macros are expanded. E.g: Help:List of datatypes is displayed as the name of this page instead of FULLPAGENAME |
Code
is preserved but macros are expanded. E.g: Help:List of datatypes is displayed as the name of this page instead of FULLPAGENAME |
Code
is preserved but macros are expanded. E.g: Help:List of datatypes is displayed as the name of this page instead of FULLPAGENAME |
| Date | Property:Has date | 2015-05-22T17:32 | 22 May 2015 17:32:00 | 2015-05-22T17:32:00 |
| Property:Has email address | president@whitehouse.gov | president@whitehouse.gov | president@whitehouse.gov | |
| Geographic coordinate | Property:Has coordinates | 32° 42' 54", -117° 9' 45" | 32° 42' 54", -117° 9' 45" | 32° 42' 54", -117° 9' 45" |
| Number | Property:Has number | 47000.11 | 47,000.11 | 47000.11 |
| Page | Property:Has example | Semantic MediaWiki | Semantic MediaWiki | Semantic MediaWiki |
| Quantity | Property:Area | 1052km² 406.177 sqmi
|
1,052 km² 406.177 sqmi
|
1052 km² |
| Record | Property:Soccer result | 22 March 2015 (Bayern München, Borussia Mönchengladbach, 0, 2) | 22 March 2015 (Bayern München, Borussia Mönchengladbach, 0, 2) | 22 March 2015 (Bayern München, Borussia Mönchengladbach, 0, 2) |
| Telephone number | Property:Telephone number | +1-800-225-5288 | +1-800-225-5288 | +1-800-225-5288 |
| Temperature | Property:Has temperatureExample | 23°C 296.15 K
73.4 °F 533.07 °R |
296.15 K 23 °C
73.4 °F 533.07 °R |
296.15 K |
| Text | Property:SomeProperty | Did you create the page for Tokyo 東京 ? Yes ✓ | Did you create the page for Tokyo 東京 ? Yes ✓ | Did you create the page for Tokyo 東京 ? Yes ✓ |
| URL | Property:Has_URL | http://www.whitehouse.gov | http://www.whitehouse.gov | http://www.whitehouse.gov |
Enumerations and "Allows value"
In addition to assigning a datatype to a property, you can also restrict the allowed values to a given set (like a whitelist for property inputs). This is done by using the special property Property:Allows value to enumerate its permitted values. This works for every datatype.
Units
The datatype Quantity allows a unit after the numeric value to distinguish values (e.g. "30 miles" versus "42 km"). To support automatic conversion and multiple unit formats, one needs to declare each supported unit as described in the documentation on custom units. Property values are then automatically converted between different units, so that users are free to use their preferred unit in each article yet still query and compare with property values in other articles.
Handling in earlier versions
Up to Semantic MediaWiki 1.5.6, datatypes had individual wiki pages in their own namespace called "Type". This was abolished to reduce the number of extra namespaces. You may still find expressions like "Type:Number" in places in this wiki. Both writings are accepted for assigning a datatype to a property.
In very early versions of SMW, properties with datatype Page were known as relations and only those used double colons (::) as the separator between property name and link text. All other properties (numbers, text, etc.) were known as attributes and had to use colon equals (:=) as the separator.
See Upgrading from SMW 0.7 to SMW 1.0 for other changes in SMW 1.0; if you're still using the older version of SMW, see semweb:Help:Annotation (SMW0.7) for documentation of Annotations in version 0.7.
