Special property "Has improper value for"

From semantic-mediawiki.org
Special property "Has improper value for"特殊属性“Has improper value for”
Has improper value for
Alerts in case the assigned value to a property is invalid
Further Information
Provided by: extension "Semantic MediaWiki "Allows to store and query data annotated to pages
Added: 1.4.2
Removed: still in use
Alias: has no alias
Optional: no
Visible: no
Annotable: no
Declarative: no
Setting: not specified
Focus: not specified
In this wiki: Property:Has improper value for
Table of Contents


The Has improper value for property is a special property in Semantic MediaWiki (SMW) with a built-in meaning: it helps to keep track of input errors in a wiki when values that are assigned to some property are invalid. These checks are made in accordance with datatype assigned to the property with the special property "Has type"Assigns a datatype to a property.

The property connects a page where some invalid input was given to the property to which this value was assigned. Thus, it can also be used in inline queries or on special page "SearchByProperty"Allows to search the wiki by properties or property value combinations to find all pages where an error occurred for a particular property. Also note that even errors that appeared when using some special property are recorded. As a simple example, we provide some erroneous input on this page:

Trying to assign "not a date" as value to property "News date" which requires a valid date: Not a date"Not a date" contains an extrinsic dash or other characters that are invalid for a date interpretation. The little warning icon alerts you of this improper value.

Has improper value for can be used for wiki gardening and maintenance, and it is also employed by Semantic MediaWiki for automatically repairing its records after the datatype of some property was changed.

This special property should never be set manually, since Semantic MediaWiki will take care of setting its value. Starting with Semantic MediaWiki 2.2.0Released on 9 May 2015 and compatible with MW 1.19.0 - 1.24.x. it is no longer possible to manually add values for this special property.1

Semantic MediaWiki 2.2.0Released on 9 May 2015 and compatible with MW 1.19.0 - 1.24.x. also introduced the "errorcount" parameter to the API-module "smwinfo"Allows to access statistical data and information about the usage of Semantic MediaWiki allowing to retrieve the number of improperly added values as well as showing them explicitly in a separate line in the "Semantic Statistics" section of the "Statistics" special page.2 Thus this creates better awareness of issues related to storing property values and helps in gardening wiki annotations.

See the property page Has improper value for to see which pages use this special property on this wiki.

Semantic Statistics on special page "Statistics" - improper annotations

Srceenshot showing the statistics for special property "Has improper value for" on special page "Statistics".

See also[edit]


  1. ^  Semantic MediaWiki: GitHub pull request gh:smw:914
  2. ^  Semantic MediaWiki: GitHub issue gh:smw:893