17.5 SEM_RDFCTX.SET_DEFAULT_POLICY

Format

SEM_RDFCTX.SET_DEFAULT_POLICY(
     index_name    IN VARCHAR2, 
     policy_name   IN VARCHAR2,
     network_owner IN VARCHAR2 DEFAULT NULL,
     network_name  IN VARCHAR2 DEFAULT NULL);

Description

Sets the default extractor policy for a semantic index that is configured with multiple extractor policies.

Parameters

index_name

Name of the semantic index for documents.

policy_name

Name of the extractor policy to be used as the default extractor policy for the specified semantic index. Must be one of the extractor policies listed in the PARAMETERS clause of the CREATE INDEX statement that created index_name.

network_owner

Owner of the semantic network. (See Table 1-2.)

network_name

Name of the semantic network. (See Table 1-2.)

Usage Notes

When you create a semantic index for documents, you can specify multiple extractor policies as a space-separated list of names in the PARAMETERS clause of the CREATE INDEX statement. As explained in Semantically Indexing Documents, the first policy from this list is used as the default extractor policy for all SEM_CONTAINS queries that do not identify an extractor policy by name. You can use the SEM_RDFCTX.SET_DEFAULT_POLICY procedure to set a different default policy for the index.

For information about semantic network types and options, see RDF Networks.

Examples

The following example sets CITY_EXTR as the default extractor policy for the ArticleIndex index.

begin
  sem_rdfctx.set_default_policy (index_name => 'ArticleIndex',
                                 policy_name => 'CITY_EXTR');
end;
/