CTX_THES Package , 25 of 30

SYN

This function returns all synonyms of a phrase as recorded in the specified thesaurus.

Syntax 1: Table Result

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

Syntax 2: String Result

CTX_THES.SYN(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 a string of the form:

 {syn1}|{syn2}|{syn3} ...

Example

String Result

Consider a thesaurus named ANIMALS that has an entry for cat as follows:

CAT 
  SYN KITTY 
  SYN FELINE

To look-up the synonym for cat and obtain the result as a string, issue the following statements:

declare 
  synonyms varchar2(2000); 
begin 
  synonyms := ctx_thes.syn('CAT','ANIMALS'); 
  dbms_output.put_line('the synonym expansion for CAT is: '||synonyms); 
end;

This code produces the following output:

the synonym expansion for CAT is: {CAT}|{KITTY}|{FELINE}

Table Result

The following code looks up the synonyms for canine and obtains the results in a table. The contents of the table are printed to the standard output.

declare  
  xtab ctx_thes.exp_tab;  
begin 
  ctx_thes.syn(xtab, 'canine', 'my_thesaurus'); 
  for i in 1..xtab.count loop 
    dbms_output.put_line(lpad(' ', 2*xtab(i).xlevel) || 
    xtab(i).xrel || ' ' || xtab(i).xphrase); 
  end loop; 
end;