CREATE_SECTION_GROUP

Creates a section group for defining sections in a text column.

When you create a section group, you can add to it zone, field, or special sections with ADD_ZONE_SECTION , ADD_FIELD_SECTION, ADD_MDATA_SECTION, or ADD_SPECIAL_SECTION .

You also use CREATE_SECTION_GROUP with CTX_DDL.SET_SEC_GRP_ATTR to set xml_enable to create an Oracle XML Search Index.

When you index, name the section group in the parameter string of CREATE INDEX or ALTER INDEX .

After indexing, query within your defined sections with the WITHIN operator.

Syntax

CTX_DDL.CREATE_SECTION_GROUP(
  group_name     in    varchar2,
  group_type     in    varchar2
);

group_name

Specify the section group name to create as section_group_name. This parameter must be unique within an owner.

group_type

Specify section group type. The group_type parameter can be one of the following:

Section Group Preference	Description
NULL_SECTION_GROUP	Use this group type when you define no sections or when you define only SENTENCE or PARAGRAPH sections. This is the default.
BASIC_SECTION_GROUP	Use this group type for defining sections where the start and end tags are of the form and . Note: This group type does not support input such as unbalanced parentheses, comments tags, and attributes. Use HTML_SECTION_GROUP for this type of input.
HTML_SECTION_GROUP	Use this group type for indexing HTML documents and for defining sections in HTML documents.
JSON_SECTION_GROUP	Use this group to create a JSON enabled context index. The JSON ENABLE attribute cannot be used with XML ENABLE. A section group can only be marked as JSON ENABLE. If it is already marked with XML ENABLE, then the path section group cannot be used for JSON ENABLE and vice versa.
XML_SECTION_GROUP	Use this group type for indexing XML documents and for defining sections in XML documents.
AUTO_SECTION_GROUP	Use this group type to automatically create a zone section for each start-tag/end-tag pair in an XML document. The section names derived from XML tags are case sensitive as in XML. Attribute sections are created automatically for XML tags that have attributes. Attribute sections are named in the form attribute@tag. Stop sections, empty tags, processing instructions, and comments are not indexed. The following limitations apply to automatic section groups: You cannot add zone, field, or special sections to an automatic section group. Automatic sectioning does not index XML document types (root elements.) However, you can define stop sections with document type. The length of the indexed tags, including prefix and namespace, cannot exceed 64 bytes. Tags longer than this are not indexed.
PATH_SECTION_GROUP	Use this group type to index XML documents. Behaves like the AUTO_SECTION_GROUP. The difference is that with this section group you can do path searching with the INPATH and HASPATH operators. Queries are also case-sensitive for tag and attribute names.
NEWS_SECTION_GROUP	Use this group for defining sections in newsgroup formatted documents according to RFC
1036.

Note: Starting with Oracle Database 18c, use of NEWS_SECTION_GROUP is deprecated in Oracle Text. Use external processing instead. If you want to index USENET posts, then preprocess the posts to use BASIC_SECTION_GROUP or HTML_SECTION_GROUP within Oracle Text. USENET is rarely used commercially.

Examples

The following command creates a section group called htmgroup with the HTML group type.

begin

ctx_ddl.create_section_group('htmgroup', 'HTML_SECTION_GROUP');

end;

The following command creates a section group called auto with the AUTO_SECTION_GROUP group type to be used to automatically index tags in XML documents.

begin

ctx_ddl.create_section_group('auto', 'AUTO_SECTION_GROUP');

end;

The following example creates an Oracle XML Search index:

exec CTX_DDL.CREATE_SECTION_GROUP('secgroup','PATH_SECTION_GROUP');
exec CTX_DDL.SET_SEC_GRP_ATTR('secgroup','xml_enable','t');
CREATE INDEX po_ctx_idx on T(X) indextype is ctxsys.context
parameters ('section group SECGROUP');

Related Topics

“WITHIN”

“Section Group Types”

“ADD_ZONE_SECTION”

“ADD_FIELD_SECTION”

“ADD_MDATA_SECTION”

“ADD_SPECIAL_SECTION”

“REMOVE_SECTION”

“DROP_SECTION_GROUP”