TT

This function returns the top term of a phrase as recorded in the specified thesaurus.

Syntax 1: Table Result

CTX_THES.TT(restab IN OUT NOCOPY EXP_TAB,
            phrase IN VARCHAR2,
            tname  IN VARCHAR2 DEFAULT 'DEFAULT');

Syntax 2: String Result

CTX_THES.TT(phrase IN VARCHAR2,
            tname  IN VARCHAR2 DEFAULT 'DEFAULT')
RETURN varchar2;

restab

Optionally, specify the name of the expansion table to store the results. This table must be of type EXP_TAB which the system defines as follows:

type exp_rec is record (
    xrel varchar2(12),
    xlevel number,
    xphrase varchar2(256)
);
type exp_tab is table of exp_rec index by binary_integer;

See Also: "CTX_THES Result Tables and Data Types" in Appendix A, "Result Tables" for more information about EXP_TAB.

phrase

Specify phrase to lookup in thesaurus.

tname

Specify thesaurus name. If not specified, system default thesaurus is used.

Returns

This function returns the top term string in the form:

{tt}

Example

Consider a thesaurus MY_THES with the following broader term entries for dog:

DOG 
   BT1 CANINE 
     BT2 MAMMAL 
       BT3 VERTEBRATE 
         BT4 ANIMAL

To look up the top term for DOG, execute the following code:

 declare 
  terms varchar2(2000); 
begin 
  terms := ctx_thes.tt('DOG','MY_THES'); 
  dbms_output.put_line('The top term for DOG is: '||terms); 
end; 

This code produces the following output:

The top term for dog is: {ANIMAL}

Related Topics

OUTPUT_STYLE

Top Term (TT) Operator in Chapter 3, "CONTAINS Query Operators"