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    <p>You did remove the property, however there were other statements related to <code>&lt;stdl184516&gt;</code> which you didn't remove.</p> <p>Here are the actual statements you have (Turtle format):</p> <pre><code>&lt;ehsanm&gt; a Ontologyowl:Student . ## Other statements &lt;ehsanm&gt; Ontologyowl:useStudyList &lt;stdl184516&gt; . &lt;stdl184516&gt; a Ontologyowl:StudyList . </code></pre> <p>So it makes sense that the removal of the <code>Ontologyowl:useStudyList</code> predicate for your <code>&lt;ehsanm&gt;</code> subject (and the statement which contains it) would leave the remaining assertion regarding <code>&lt;stdl184516&gt;</code>'s type.</p> <p>The reason why you don't have this problem with literals is that you have no literals as subjects of a statement (they are only objects of a statement). So removing that statement removes the literal (and all references to it). With resources as a statement's object, there could be additional statements regarding that resource (as is the case in your example).</p> <p>RDF considers literals disjoint, meaning they are all different (even if they have the same value). This why removing a predicate to a literal (the "link" to it if you want to think of it that way) also removes the literal.</p> <p><em>Update (to add to Mr. Lame's response):</em> Conceptually, RDF is about edges (relations/predicates) in a graph of nodes (resources). The notion of deleting a node is contrary to RDF; it implies the node (resource) has meaning on it's own. Even typing a resource by asserting its <code>rdf:type</code> is a node/edge/node statement. The node URI alone is considered opaque and has no semantics beyond being a unique identifier. This is why RDF does not allow "bare" nodes (a node outside of a statement) -- they have no inherent meaning.</p> <p>To extend the question posed by Ehsan, deleting a node would actually delete all of its incoming/outgoing predicates. This doesn't truly "delete" the node, it actually removes all statements/assertions which reference it (think of it as "hidden" when no statements reference it).</p>
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    1. PORemoving individuals & properties from RDF
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    1. COThank you very much for guidance. I will Check again and add some code to see if it works. Thanks again
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