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A "semantic network" is an Oracle construct that is used to support the creation and use of "semantic models" in a tablespace. When an OracleContext is initialized, it will create a model using the semantic network. To create the semantic network, use the following form:
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EXECUTE
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SEM_APIS.CREATE_SEM_NETWORK('rdf_tblspace');
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(the parameter is the name of the tablespace for which you want to create the network.)
For more information about installing and using Oracle semantic extensions, see the Oracle see the Oracle semantic technologies overview.