Displaying data help

I am new with sparql. I have this employee class and I want to print out the columns in that class.

Employee class

Instances

My query:
SELECT *
WHERE {
?Employee a :employee ;
:LastName ?LastName ;
:Location ?Location.
}

I am getting an empty output. Can you help me modify my query?

Try the following query

SELECT *
WHERE {
?Employee a :employee ;
<http://api.stardog.com#LastName> ?LastName ;
<http://api.stardog.com#Location> ?Location.
}

The properties aren't in the default Stardog empty namespace.

Thank you. Can you please tell me how do I set the properties in default Stardog namespace? Do I do that during the import?

I tried to add as below but not working. Am I missing something?

SkillList:useYourDefineHere

maybe because the "default" ":" is set to http://api.stardog.com/

if you want to use default

:useYourDefineHere

you would like to replace the first one http://api.stardog.com/ to

http:/api.stardog.com/SkillList/YourDefineHere

unless you want your IRI looks this

http:/api.stardog.com#SkillListYourDefineHere

paste part of your .ttl file to check what IRI looks like?


:Permisson <http://kim.jong.un/onto#Permission>

You're close. You probably want to make it

Prefix: SkillList IRI: http://api.stardog.com#

which would make your query

SELECT *
WHERE {
    ?Employee a :employee ;
    SkillList:LastName ?LastName ;
    SkillList:Location ?Location.
}

Some explanation on what's going on here. Namespaces are just a shorthand for writing out a long url. The prefix is replaced by whatever namespace you assign to it. You can always write out the full url surrounded by angle brackets to indicate that it's a url. Namespaces can be anything you want including an empty namespace which would be just a :.

As a convenience to the user Stardog automatically assigns this namespace to http://api.stardog.com/ . The user is free to change that if they like. As you can see in your query the :employee uses that namespace.

What may be somewhat confusing is that the properties LastName and Location are in a slightly different namespace, http://api.starodg.com#. Take note of the tailing # rather than a /.

You can either write out the complete url or define a namespace for http://api.stardog.com#.

In your example you defined prefix: SkillList, iri: http://api.stardog.com#SkillList which whould translate to the following prefixes for your query

<http://api.stardog.com#SkillListLastName> <http:///api.starod.com#SkillListLocation>

and would not return any results since it doesn't match what's in your database.

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