载入图片到数据库

--载入图片到数据库
declare
    alob        blob;
    afile       bfile;
    amount      int;
    src_offset  int := 1;
    dest_offset int := 1;
begin
    select photo into alob from photo_tab  for update;
    afile := bfilename('G', 'a.jpg');
    dbms_lob.fileopen(afile, 0);
    amount := dbms_lob.getlength(afile);
    dbms_lob.loadblobfromfile(alob, afile, amount, dest_offset, src_offset);
    dbms_lob.fileclose(afile);
    commit;
end;
/

--从数据库读取图片到文件.
declare
    alob   blob;
    amount   int;
    offset   int := 1;
    totalw   int := 0;
    currentw int;
    buffer   raw(2000);
    f        utl_file.file_type;
begin
    select photo into alob from photo_tab ;
    amount := dbms_lob.getlength(alob);
    f      := utl_file.fopen('G', 'b.jpg', 'ab', 2000);
    loop
        if ((amount - totalw) >= 2000) then
            currentw := 2000;
        else
            currentw := amount - totalw;
        end if;
        dbms_lob.read(alob, currentw, totalw + 1, buffer);
        utl_file.put_raw(f, buffer);
        totalw := totalw + currentw;
        exit when totalw = amount;
    end loop;
    utl_file.fclose(f);
end;
/