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Re: [dotNetRDF-Support] DELETE QUERY
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From: Glen W. <gle...@bc...> - 2011-11-22 13:48:56
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Hi Rob,
FYI .... the following code is updating the graph as I expect and storing
only a single value in the resultant RDF/XML file, i.e. working as I need
...(although I need to now test downstream use of the file ... )
However .... is it efficient ? Is it the best way ? Note I also have to
revisit this as it is NOT working for strings, but that may be something
special for the strings that are being displayed as other strings have not
been classified correctly. I read that the nodes are immutable so I need to
retract and assert rather than
If aTriple.Object.NodeType = NodeType.Literal Then
aTriple.Object.Value = szLiteral
Public Sub UpdateRDF(ByVal szKey As String, ByVal szProperty As String,
ByVal szLiteral As String)
' v2 : update the graph
' OIMGraph has the graph
' lets try getting the triples with the szKey and szProperty
Dim tmpGraph As New Graph
Dim tsResults As Triple()
Dim aTriple As Triple, tplKey As Triple, tplProperty As Triple
Dim szSubject As String, szPredicate As String
Dim ndSubject As VDS.RDF.UriNode
Dim ndPredicate As VDS.RDF.UriNode
Dim szNS As String
Dim iPos As Integer
szSubject = ""
szPredicate = ""
For Each aTriple In OIMGraph.Triples
If aTriple.Object.ToString = szKey Then
tplKey = aTriple
szSubject = tplKey.Subject.ToString
szPredicate = ""
End If
If aTriple.Object.ToString = szProperty Then
If szSubject = aTriple.Subject.ToString Then
tplProperty = aTriple
szPredicate = tplProperty.Subject.ToString
Else
szSubject = ""
szPredicate = ""
End If
End If
If szSubject <> "" And szPredicate <> "" Then
If aTriple.Object.NodeType = NodeType.Literal Then
OIMGraph.Retract(aTriple)
Dim nodNew As LiteralNode
nodNew = OIMGraph.CreateLiteralNode(szLiteral)
Dim tplNew As New Triple(aTriple.Subject,
aTriple.Predicate, nodNew)
OIMGraph.Assert(tplNew)
' note we have altered the collection so we have to exit
!!
Exit For
End If
Debug.Print("<SUBJ:" & aTriple.Subject.ToString & "><PRED:"
& aTriple.Predicate.ToString & "><OBJC:" & aTriple.Object.ToString & ">")
End If
Next
End Sub
Feedback welcome ...
Glen
From: Glen Worrall [mailto:gle...@bc...]
Sent: 22 November 2011 06:56
To: dot...@li...
Subject: Re: [dotNetRDF-Support] DELETE QUERY
Thanks Rob,
FYI the TripleStore Writers do not work with VB.NET WinForm applications
http://www.vbforums.com/showthread.php?t=552398
Therefore ... apologies ... for what is about to follow ...
This is meant to delete the original triple ...
szSPARQLDelete = szPrefix & "DELETE DATA {" & _
szSubject & " " & szPredicate & " " & szObject & "}"
aTripleStore.ExecuteUpdate(szSPARQLDelete)
i = InStr(szObject, "^^")
szObject = szLiteral '& Mid$(szObject, i) ' .substring seems to
return 1 char short
'nObject = OIMGraph.CreateLiteralNode(szObject)
'and replace it with the new value
szSPARQLInsert = szPrefix & "INSERT DATA {" & _
szSubject & " " & szPredicate & " " & szObject & "}"
'OIMGraph.Assert(New Triple(nSubject, nPredicate, nObject))
aTripleStore.ExecuteUpdate(szSPARQLInsert)
' TripleStoreWriters all cause an issue with WinForms
' Dim rdfWriter As New TriGWriter
' aTripleStore.SaveToFile("d:\data\testing.trig",
rdfWriter)
' Dim rdfWriterX As New TriXWriter
' aTripleStore.SaveToFile("d:\data\testing.trix",
rdfWriter)
' Dim rdfWriterN As New NQuadsWriter
' aTripleStore.SaveToFile("d:\data\testing.trin",
rdfWriterN)
' so we need to create a graph from the triplestore !!
SaveRDF("d:\data\testing.owl", aTripleStore)
End If
End Sub
Public Sub SaveRDF(ByVal szFilename As String, ByVal aTripleStore As
TripleStore)
' aTripleStore.SaveToFile(szFilename) ha if only
Dim rdfWriter As New RdfXmlWriter
Dim sparqlparser As New SparqlQueryParser
Dim query As SparqlQuery
Dim results As Object
query = sparqlparser.ParseFromString("CONSTRUCT { ?s ?p ?o } WHERE
{?s ?p ?o}")
results = aTripleStore.ExecuteQuery(query)
If (results.GetType.ToString = "VDS.RDF.Graph") Then
rdfWriter.Save(results, szFilename)
End If
End Sub
All runs .... but ...
note the edited triple
<ns0:Thing
rdf:about="http://example.org/data#GATE_VALVE.DGNEC__1543070000__ECXA__2.DRY
_WEIGHT">
<ns63:R10528152386 xmlns:ns63="http://tpl.rdlfacade.org/data#"
rdf:resource="http://rdl.rdlfacade.org/data#R39123699723" />
<ns64:R11450580697 xmlns:ns64="http://tpl.rdlfacade.org/data#"
rdf:resource="http://example.org/data#GATE_VALVE.DGNEC__1543070000__ECXA__2"
/>
<ns65:R56806886394 xmlns:ns65="http://tpl.rdlfacade.org/data#"
rdf:resource="http://rdl.rdlfacade.org/data#R66709707623" />
<ns66:R65789235245 xmlns:ns66="http://tpl.rdlfacade.org/data#"
rdf:datatype="&xsd;float">0</ns66:R65789235245>
<rdf:type rdf:resource="http://tpl.rdlfacade.org/data#R33612674560" />
<xsd:R65789235245 rdf:datatype="&xsd;integer">70</xsd:R65789235245>
</ns0:Thing>
compared to an unedited triple
<ns0:Thing
rdf:about="http://example.org/data#HORIZONTAL_CENTRIFUGAL_PUMP.DGNEC__151607
0000__ECXA__2.DRY_WEIGHT">
<ns136:R10528152386 xmlns:ns136="http://tpl.rdlfacade.org/data#"
rdf:resource="http://rdl.rdlfacade.org/data#R39123699723" />
<ns137:R11450580697 xmlns:ns137="http://tpl.rdlfacade.org/data#"
rdf:resource="http://example.org/data#HORIZONTAL_CENTRIFUGAL_PUMP.DGNEC__151
6070000__ECXA__2" />
<ns138:R56806886394 xmlns:ns138="http://tpl.rdlfacade.org/data#"
rdf:resource="http://rdl.rdlfacade.org/data#R66709707623" />
<ns139:R65789235245 xmlns:ns139="http://tpl.rdlfacade.org/data#"
rdf:datatype="&xsd;float">0</ns139:R65789235245>
<rdf:type rdf:resource="http://tpl.rdlfacade.org/data#R33612674560" />
</ns0:Thing>
the original value and new value are stored ...
Note also the nsxxx peculiarity ...
Glen
From: Rob Vesse [mailto:rv...@do...]
Sent: 21 November 2011 17:40
To: Glen Worrall
Subject: RE: DELETE QUERY
Hi Glen
SPARQL Query and Update are two separate standards and so the library
handles them separately. If you want to run updates then you need to use
the ExecuteUpdate() method instead. See [1] for alternative ways to apply
updates.
If you want to create typed literals then you need to use the two argument
version of CreateLiteralNode() which takes a URI as the second argument for
the datatype. Or if you have .Net primitive types you can use the
ToLiteral() extension methods to turn these directly into literals with
appropriate types.
SparqlGUI was designed as a query only tool, I may add update to it in the
future but currently it does not support this.
If you have further questions please let me know,
Rob Vesse
[1]: http://www.dotnetrdf.org/content.asp?pageID=Updating%20with%20SPARQL
_____
From: "Glen Worrall" <gle...@bc...>
Sent: Monday, November 21, 2011 9:13 AM
To: rv...@do...
Subject: RE: DELETE QUERY
Hi Rob,
Just to let you know I have been trying this with other options ...
If szSubject <> "" Then
szPrefix = ""
' seems that the subject. predicate, object MUST have a
qualifier ... !!!
iPos = InStr(szSubject, "#")
szQualifier = Mid$(szSubject, 1, iPos)
szURI = New Uri(szQualifier)
szNS = OIMGraph.NamespaceMap.GetPrefix(szURI)
If szNS = "" Then
szNS = "ns" & gNSCounter.ToString
OIMGraph.NamespaceMap.AddNamespace(szNS, szURI)
gNSCounter = gNSCounter + 1
End If
'szPrefix = "PREFIX q1: <" & szQualifier & "> "
szSubject = szNS & ":" & Mid$(szSubject, iPos + 1)
iPos = InStr(szPredicate, "#")
szQualifier = Mid$(szPredicate, 1, iPos)
szURI = New Uri(szQualifier)
szNS = OIMGraph.NamespaceMap.GetPrefix(szURI)
If szNS = "" Then
szNS = "ns" & gNSCounter.ToString
OIMGraph.NamespaceMap.AddNamespace(szNS, szURI)
gNSCounter = gNSCounter + 1
End If
'szPrefix = szPrefix & "PREFIX q2: <" & szQualifier & "> "
szPredicate = szNS & ":" & Mid$(szPredicate, iPos + 1)
i = InStr(szObject, "^^")
iPos = InStr(szObject, "#")
' note we cannot get here unless Object is a Literal ... !!!
szQualifier = Mid$(szObject, i + 2, iPos - i - 1)
' szPrefix = szPrefix & "PREFIX q3: <" & szQualifier
& "> "
szURI = New Uri(szQualifier)
szNS = OIMGraph.NamespaceMap.GetPrefix(szURI)
If szNS = "" Then
szNS = "ns" & gNSCounter.ToString
OIMGraph.NamespaceMap.AddNamespace(szNS, szURI)
gNSCounter = gNSCounter + 1
End If
szObject = Mid$(szObject, 1, i - 1) & "^^" & szNS & ":" &
Mid$(szObject, (iPos + 1))
nSubject = OIMGraph.CreateUriNode(szSubject)
nPredicate = OIMGraph.CreateUriNode(szPredicate)
nObject = OIMGraph.CreateLiteralNode(szObject)
OIMGraph.Retract(New Triple(nSubject, nPredicate, nObject))
' the following fails ... seems execute query cannot work with
DELETE & INSERT
' szSPARQLDelete = szPrefix & "DELETE DATA WHERE {" &
_
' szSubject & " " & szPredicate & " " & szObject
& "}"
' aTripleStore.ExecuteQuery(szSPARQLDelete)
i = InStr(szObject, "^^")
szObject = szLiteral & Mid$(szObject, i) ' .substring seems to
return 1 char short
nObject = OIMGraph.CreateLiteralNode(szObject)
'szSPARQLInsert = szPrefix & "INSERT DATA {" & _
' szSubject & " " & szPredicate & " " & szObject & "}"
OIMGraph.Assert(New Triple(nSubject, nPredicate, nObject))
Gets me much closer .... but the RDF file now has double values ....
Note an edited value ...
<owl:Thing
rdf:about="&ex;GATE_VALVE.DGNEC__1543070000__ECXA__2.INSIDE_DIAMETER">
<tpl:R10528152386 rdf:resource="&part4;R34755432270" />
<tpl:R11450580697
rdf:resource="&ex;GATE_VALVE.DGNEC__1543070000__ECXA__2" />
<tpl:R56806886394 rdf:resource="&part4;R37466989245" />
<tpl:R65789235245>100^^xsd:float</tpl:R65789235245>
<tpl:R65789235245 rdf:datatype="&xsd;float">0</tpl:R65789235245>
<type rdf:resource="&tpl;R33612674560" />
</owl:Thing>
Unedited
<owl:Thing
rdf:about="&ex;GATE_VALVE.DGNEC__1543070000__ECXA__2.INSULATION_THICKNESS">
<tpl:R10528152386 rdf:resource="&part4;R34755432270" />
<tpl:R11450580697
rdf:resource="&ex;GATE_VALVE.DGNEC__1543070000__ECXA__2" />
<tpl:R56806886394 rdf:resource="&part4;R93517282348" />
<tpl:R65789235245 rdf:datatype="&xsd;float">0</tpl:R65789235245>
<type rdf:resource="&tpl;R33612674560" />
</owl:Thing>
If I remove the "additional" incorrect triple from the property graph ...
then
<owl:Thing
rdf:about="&ex;GATE_VALVE.DGNEC__1543070000__ECXA__2.ELEVATION">
<tpl:R10528152386 rdf:resource="&part4;R82749412674" />
<tpl:R11450580697
rdf:resource="&ex;GATE_VALVE.DGNEC__1543070000__ECXA__2" />
<tpl:R56806886394 rdf:resource="&part4;R60277357355" />
<tpl:R65789235245>1000^^xsd:float</tpl:R65789235245>
<type rdf:resource="&tpl;R33612674560" />
</owl:Thing>
This prevents my app from working (ie it no longer recognises literal
values)
Again I am just looking for a "best" practice rather than debugging my
examples
Thanks
Glen
_____________________________________________
From: Glen Worrall [mailto:gle...@bc...]
Sent: 21 November 2011 09:50
To: 'rv...@do...'
Subject: DELETE QUERY
Hi Rob,
sorry to bother you but wanted to check if the DELETE option in a SPARQL
query is working in dotNETRDF ...
I have tried various modifications etc to my file and seem to now get the
same error in my code as in the SPARQL GUI
PREFIX ex: < <http://example.org/data> http://example.org/data#>
PREFIX tpl: < <http://tpl.rdlfacade.org/data>
http://tpl.rdlfacade.org/data#>
PREFIX xmlschema: < <http://www.w3.org/2001/XMLSchema>
http://www.w3.org/2001/XMLSchema#>
DELETE
{ex:GATE_VALVE.DGNEC__1543070000__ECXA__2.DRY_WEIGHT tpl:R65789235245
0^^xmlschema:float}
Note the prefixes have been created otherwise I received example.org is not
a valid QName exception.
Really all I want to do is update the literal in the triple store and then
write out the file ...
ie
open OWL file
display literals to user
edit literals as required
save OWL file to .OWL file
Is DELETE supported in TripleStore.ExecuteSQL(query as String) ?
I can of course send you the .OWL file I am using for testing
Thanks
Glen
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