USER_DATASTORE with BLOB_LOC Example

The following procedure might be used with OUTPUT_TYPE BLOB_LOC:

procedure myds(rid in rowid, dataout in out nocopy blob)
is
  l_dtype varchar2(10);
  l_pk    number;
begin
  select dtype, pk into l_dtype, l_pk from mytable where rowid = rid;
  if (l_dtype = 'MOVIE') then
    select movie_data into dataout from movietab where fk = l_pk;
  elsif (l_dtype = 'SOUND') then
    select sound_data into dataout from soundtab where fk = l_pk;
  end if;
end;

The user appowner creates the preference as follows:

begin

ctx_ddl.create_preference('myud', 'user_datastore');
ctx_ddl.set_attribute('myud', 'procedure', 'myproc');
ctx_ddl.set_attribute('myud', 'output_type', 'blob_loc');

end;