String Split/ String replace based on character length - sql

Question

Here my problem in a notes column having 2000 characters max, i want my string output based on 35 characters, ya i need to replace <br> tag after 30 characters in the string.. example string "hi hello how are you doing out there, need your help!", i need out put as "hi hello how are you doing out<br> there, need your help! similar i need to calculate the sting length and have to split it 35+35+35.. i don't know how to perform this in sql/plsql.
select substr(note,1,(instr(note, ' ',35)))||'<br>'||substr(note,instr(note, ' ',35),
(instr(note, ' ',35)))notes from test

Answer 1

DECLARE
CURSOR notes_cur IS
SELECT 1 note_id, 'hi hello how are you doing out there, need your help! hi hello how are you doing out there, need your help!' note FROM DUAL UNION ALL
SELECT 2, 'hi hello how are you doing out there, need your help! hi hello how are you doing out there, need your help!' note FROM DUAL;
TYPE notes_ntt IS TABLE OF notes_cur%ROWTYPE;
l_notes notes_ntt;
l_loop_counter NUMBER;
l_split notes_ntt := notes_ntt();
l_space_start NUMBER;
l_string_start NUMBER;
l_space_position NUMBER;
BEGIN
OPEN notes_cur;
FETCH notes_cur BULK COLLECT INTO l_notes;
CLOSE notes_cur;
FOR indx IN 1..l_notes.COUNT LOOP
l_space_start := 33;
l_string_start := 1;
l_loop_counter := TRUNC(LENGTH(l_notes(indx).note) / 35);
FOR note IN 1..l_loop_counter LOOP
l_split.EXTEND;
l_split(l_split.LAST).note_id := l_notes(indx).note_id;
l_space_position := INSTR(l_notes(indx).note, CHR(32), l_space_start, 1);
l_split(l_split.LAST).note := SUBSTR
(
l_notes(indx).note
, l_string_start
, CASE
WHEN l_space_position = 0
THEN l_string_start
ELSE l_space_position - l_string_start
END
) || CHR(10);
l_space_start := l_space_position + 33;
l_string_start := l_space_position + 1;
END LOOP;
END LOOP;
FOR indx IN 1..l_split.COUNT LOOP
DBMS_OUTPUT.PUT_LINE(l_split(indx).note_id || ' ' || l_split(indx).note);
NULL;
END LOOP;
END;
/*
1 hi hello how are you doing out there,
1 need your help! hi hello how are
1 you doing out there, need your help!
2 hi hello how are you doing out there,
2 need your help! hi hello how are
2 you doing out there, need your help!
*/

Answer 2

You could do this:
declare
l_in_string varchar2(1000) := 'hi hello how are you doing out there, need your help!';
l_out_string varchar2(1000);
begin
while length(l_in_string) > 35 loop
l_out_string := l_out_string || substr(l_in_string, 1, 35) || '<br>';
l_in_string := substr(l_in_string, 36);
end loop;
l_out_string := l_out_string || l_in_string;
dbms_output.put_line(l_out_string);
end;
However this is quite likely to break mid-word e.g.
hi hello how are you doing out there, need your help!
You would need to write more sophisticated code if you want to break on spaces only.