Oracle CLOB can't insert beyond 4000 character?

Question

How to insert more than 4000 characters to CLOB type column?

--create test table s
create table s
(
      a clob
);
insert into s values(\'>4000 char\')
<         


        

Answer 1

The maximum for one time insertion is 4000 characters (the maximum string literal in Oracle). However you can use the lob function dbms_lob.append() to append chunks of (maximum) 4000 characters to the clob:

CREATE TABLE don (x clob);


DECLARE 
 l_clob clob;
BEGIN
  FOR i IN 1..10
  LOOP
    INSERT INTO don (x) VALUES (empty_clob()) --Insert an "empty clob" (not insert null)
    RETURNING x INTO l_clob;

    -- Now we can append content to clob (create a 400,000 bytes clob)
    FOR i IN 1..100
    LOOP
      dbms_lob.append(l_clob, rpad ('*',4000,'*'));
      --dbms_lob.append(l_clob, 'string chunk to be inserted (maximum 4000 characters at a time)');
    END LOOP;
  END LOOP;
END;