Special properties

From semantic-mediawiki.org
Special properties
Provides an overview about properties that are build into Semantic MediaWiki.
Table of Contents

This page describes the 61 special properties that are built-in to Semantic MediaWiki (SMW). They are needed to make the system work. They appear in a page's factbox, on special page "Properties"Lists properties and displays their usage and on special page "Browse"Shows all properties and their values annotated to a page in italic. Since Semantic MediaWiki 1.4.0Released on 21 November 2008 and compatible with MW 1.13.x - 1.16.x., special properties can be used in browsing interfaces and inline queries just like all other properties. Also see the help page properties and types for more information.

Special properties may also be provided by extensions to Semantic MediaWiki like, e.g. extension "Semantic Extra Special Properties"Adds some extra special properties to all pages or extension "Semantic Cite"Allows to manage citation resources using semantic annotations, etc. These however are currently not being documented here.

The names and aliases of special properties are reserved and cannot be used for other properties. Additionally special properties should only be used according to their documented purpose! It is not necessary to create pages for special properties. They will perform their special behavior even if your wiki does not have a property page for it.

Overview[edit]

The following table gives an overview of all 61 special properties provided by Semantic MediaWiki:

Name Description Help Added Key
Allows value Lists one permissible value for a property help page 1.0
_PVAL
Corresponds to Gives the conversion factor for some unit of a physical quantity and the possible names for that unit help page 1.0
_CONV
Display units Specifies the a comma-separated list of units or formats that a property should use in display help page 1.0
_UNIT
Equivalent URI Marks a page in the wiki as having a well-known meaning beyond this wiki, in an external URI help page 1.0
_URI
Has type Assigns a datatype to a property help page 1.0
_TYPE
Imported from Allows users to reuse elements of external vocabularies directly within the wiki help page 1.0
_IMPO
Provides service Adds service links to properties help page 1.0
_SERV
Subproperty of Lets you indicate that one property is a subproperty of another help page 1.0
_SUBP
Modification date Holds a fixed value that corresponds to the date of the last modification of each page help page 1.4.0
_MDAT
Has improper value for Alerts in case the assigned value to a property is invalid help page 1.4.2
_ERRP
Has fields Defines a short list of fields with a fixed type and order for datatype Record help page 1.5.0
_LIST
Subcategory of Lets you explicitly indicate that one category is a subcategory of another help page 1.5.0
_SUBC
Creation date Holds a fixed value that corresponds to the date of the first revision of each page help page 1.7.0
_CDAT
Has subobject Holds the subobjects set on a page help page 1.7.0
_SOBJ
Is a new page Holds a value marking a page as being new or not help page 1.7.1
_NEWP
Last editor is Holds the page name of the user who created the last page revision help page 1.7.1
_LEDT
Has query Links a page to the subobject created by a query recording its profile help page 1.8.0
_ASK
Query depth Holds the value of the property depth of a query help page 1.8.0
_ASKDE
Query format Holds the name of the result format used in a query help page 1.8.0
_ASKFO
Query size Holds the value of the number of conditions in a query help page 1.8.0
_ASKSI
Query string Holds the conditions of the query as a string help page 1.8.0
_ASKST
Query duration Holds the value of the duration a query took to execute help page 1.9.0
_ASKDU
MIME type Holds the MIME type of an uploaded file help page 1.9.1
_MIME
Media type Holds the Media type of an uploaded file help page 1.9.1
_MEDIA
Allows pattern Pattern to match a permissible value help page 2.4.0
_PVAP
Display precision of Allows to define the display precision in digits help page 2.4.0
_PREC
Display title of Holds a specific denote title for an entity help page 2.4.0
_DTITLE
Has property description Adds localizable context help to properties help page 2.4.0
_PDESC
Has uniqueness constraint Allows to restrict value annotation to be unique help page 2.4.0
_PVUC
Language code Handles BCP47 conform language codes specifying the language of the annotated text help page 2.4.0
_LCODE
Processing error Holds a "container" with further information about a problem and allows to explore and rectify it help page 2.4.0
_ERRC
Processing error message Holds a textual description of an error which occurred during the processing of a page help page 2.4.0
_ERRT
Allows value list Adds a reference to a list of permissible values for a property help page 2.5.0
_PVALI
External formatter URI Declares an external URL with placeholders $1, $2 help page 2.5.0
_PEFU
External identifier Specifies an external identifier help page 2.5.0
_PEID
Has preferred property label Adds localizable labels to a property help page 2.5.0
_PPLB
Is edit protected Stores the status of an edit restriction of a page help page 2.5.0
_EDIP
Query parameters Holds the parameters a query used to select its output help page 2.5.0
_ASKPA
Query source Holds the identifier of an alternative (e.g. remote) query source help page 2.5.0
_ASKSC
Change propagation Holds the new property specification of a property or category page help page 3.0.0
_CHGPRO
Is property group Marks a category for holding properties belonging to a property group help page 3.0.0
_PPGR
Query state Holds the status code a query uses to define its internal state help page 3.0.0
_ASKCO
Schema definition Holds the definition of a schema what was added to namespace "smw/schema" help page 3.0.0
_SCHEMA_DEF
Schema description Holds the description of a schema what was added to namespace "smw/schema" help page 3.0.0
_SCHEMA_DESC
Schema link Holds the link of a schema what was added to namespace "smw/schema" help page 3.0.0
_SCHEMA_LINK
Schema tag Holds the tags to a schema what was added to namespace "smw/schema" help page 3.0.0
_SCHEMA_TAG
Schema type Holds the type of a schema what was added to namespace "smw/schema" help page 3.0.0
_SCHEMA_TYPE
Attachment link Holds the links to files embedded on a page help page 3.1.0
_ATTCH_LINK
Constraint schema Holds the name of a constraint schema which is not restricted to single constraint types help page 3.1.0
_CONSTRAINT_SCHEMA
Processing error type Holds the type of an error which occurred during the processing of a page help page 3.1.0
_ERR_TYPE
Profile schema Holds the name of a profile schema which declares characteristics for annotations help page 3.1.0
_PROFILE_SCHEMA

See also[edit]

Note[edit]

Special properties can also be classified according to a certain behaviour they have or allow for. See the following help pages for further information:

Applying styles[edit]

In case you would like to make special properties easier to be identified in the factbox, on special page "Properties"Lists properties and displays their usage and on special page "Browse"Shows all properties and their values annotated to a page just add, e.g. the following CSS code to the MediaWiki:Common.css page.

.smwbuiltin a,
.smwbuiltin a.new {
    color: #ff8000;
}
Special properties are are already printed in italics prior to the extra formatting mentioned here.

"Has description</br>" contains a listed "LF" character as part of the property label and has therefore been classified as invalid. "Has description</br>" contains a listed "LF" character as part of the property label and has therefore been classified as invalid. "Has description</br>" contains a listed "LF" character as part of the property label and has therefore been classified as invalid. "Has description</br>" contains a listed "LF" character as part of the property label and has therefore been classified as invalid. "Has description</br>" contains a listed "LF" character as part of the property label and has therefore been classified as invalid.