POLICY_THEMES

Generates a list of themes for a document. With this procedure, no CONTEXT index is required.

Syntax

ctx_doc.policy_themes(policy_name    in VARCHAR2,
	                      document       in [VARCHAR2|CLOB|BLOB|BFILE],
                      restab         in out nocopy theme_tab,
                      full_themes    in BOOLEAN default FALSE,
                      num_themes     in number    default 50
                      language       in VARCHAR2 default NULL,
                      format         in VARCHAR2 default NULL,
                      charset        in VARCHAR2 default NULL
);

policy_name

Specify the policy you create with CTX_DDL.CREATE_POLICY.

document

Specify the document for which to generate a list of themes.

restab

Specify the name of the theme_tab PL/SQL index-by-table type.

See Also: “THEMES” for more information about the structure of the theme_tab type.

full_themes

Specify whether this procedure generates a single theme or a hierarchical list of parent themes (full themes) for each document theme.

Specify TRUE for this procedure to write full themes to the THEME column of the result table.

Specify FALSE for this procedure to write single theme information to the THEME column of the result table. This is the default.

num_themes

Specify the maximum number of themes to retrieve. For example, if you specify 10, up to first 10 themes are returned for the document. The default is 50.

If you specify 0 or NULL, this procedure returns all themes in a document. If the document contains more than 50 themes, only the first 50 themes show conceptual hierarchy.

language

Specify the language of the document. Use an Oracle Text supported language value as you would in the language column of the base table. See “MULTI_LEXER” in Oracle Text Indexing Elements.

format

Specify the format of the document. Use an Oracle Text supported format value, either TEXT, BINARY or IGNORE as you would specify in the format column of the base table. For more information, see the format column description in “CREATE INDEX” in Oracle Text SQL Statements and Operators .

charset

Specify the character set of the document. Use an Oracle Text supported value as you would specify in the charset column of the base table. See “Filter Types”.

Example

Create a policy:

exec ctx_ddl.create_policy('mypolicy');

Run themes:

declare
  la      varchar2(200);
  rtab    ctx_doc.theme_tab;
begin
   ctx_doc.policy_themes('mypolicy',
           'To define true madness, What is''t but to be nothing but mad?', rtab);
   for i in 1..rtab.count loop
     dbms_output.put_line(rtab(i).theme||':'||rtab(i).weight);
   end loop;
end;