SEM_APIS.COMPOSE_RDF

Format

SEM_APIS.COMPOSE_RDF_TERM(
     value_name    IN VARCHAR2, 
     value_type    IN VARCHAR2, 
     literal_type  IN VARCHAR2, 
     language_type IN VARCHAR2 
     ) RETURN VARCHAR2;

or

SEM_APIS.COMPOSE_RDF_TERM(
     value_name    IN VARCHAR2, 
     value_type    IN VARCHAR2, 
     literal_type  IN VARCHAR2, 
     language_type IN VARCHAR2, 
     long_value    IN CLOB, 
     options       IN VARCHAR2 DEFAULT NULL, 
     ) RETURN CLOB;

Description

Creates and returns an RDF term using the specified parameters.

Parameters

value_name: Value name. Must match a value in the VALUE_NAME column in the RDF_VALUE$ table (described in Statements) or in the var attribute returned from SEM_MATCH table function.
value_type: The type of text information. Must match a value in the VALUE_TYPE column in the RDF_VALUE$ table (described in Statements) or in the var$RDFVTYP attribute returned from SEM_MATCH table function.
literal_type: For typed literals, the type information; otherwise, null. Must either be a null value or match a value in the LITERAL_TYPE column in the RDF_VALUE$ table (described in Statements) or in the var$RDFLTYP attribute returned from SEM_MATCH table function.
language_type: Language tag. Must match a value in the LANGUAGE_TYPE column in the RDF_VALUE$ table (described in Statements) or in the var$RDFLANG attribute returned from SEM_MATCH table function.
long_value: The character string if the length of the lexical value is greater than 4000 bytes. Must match a value in the LONG_VALUE column in the RDF_VALUE$ table (described in Statements) or in the var$RDFCLOB attribute returned from SEM_MATCH table function.
options: (Reserved for future use.)

Usage Notes

If you specify an inconsistent combination of values for the parameters, this function returns a null value. If a null value is returned but you believe that the values for the parameters are appropriate (reflecting columns from the same row in the RDF_VALUE$ table or from a SEM_MATCH query for the same variable), contact Oracle Support.

Examples

The following example returns, for each member of the family whose height is known, the RDF term for the height and also just the value portion of the height.

SELECT x, SEM_APIS.COMPOSE_RDF_TERM(h, h$RDFVTYP, h$RDFLTYP, h$RDFLANG)
       h_rdf_term, h
  FROM TABLE(SEM_MATCH(
    '{?x :height ?h}',
    SEM_Models('family'),
    null, 
    SEM_ALIASES(SEM_ALIAS('','http://www.example.org/family/')),
    null))
ORDER BY x;
X
--------------------------------------------------------------------------------
H_RDF_TERM
--------------------------------------------------------------------------------
H
--------------------------------------------------------------------------------
http://www.example.org/family/Cathy
"5.8"^^<http://www.w3.org/2001/XMLSchema#decimal>
5.8
 
http://www.example.org/family/Cindy
"6"^^<http://www.w3.org/2001/XMLSchema#decimal>
6
 
http://www.example.org/family/Jack
"6"^^<http://www.w3.org/2001/XMLSchema#decimal>
6
 
http://www.example.org/family/Tom
"5.75"^^<http://www.w3.org/2001/XMLSchema#decimal>
5.75
 
4 rows selected.

The following example returns the RDF terms for a few of the values stored in the RDF_VALUE$ table.

SELECT SEM_APIS.COMPOSE_RDF_TERM(value_name, value_type, literal_type,
     language_type)
  FROM RDF_VALUE$ WHERE ROWNUM < 5;

SEM_APIS.COMPOSE_RDF_TERM(VALUE_NAME,VALUE_TYPE,LITERAL_TYPE,LANGUAGE_TYPE)
--------------------------------------------------------------------------------
<http://www.w3.org/1999/02/22-rdf-syntax-ns#object>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#subject>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#Property>