Help!!urgent!!can not insert/update clob:the row containing the lob is not locked

Question

Hi,
could you do me help?
i can not insert a string into a oracle clob field, it echo as:
ORA22920 row containing the lob value is not locked. ORA 06512 at "SYS.DBMS_LOB" line 708
ORA 06512 at line 1;
what its means? please.
my table defined as : create table clob1(id number(5),mclob clob default empty_clob()); the id is create by a sequece of test_sequence automaticly.
my code as belows:
import java.io.*;
import java.sql.*;
//import oracle.sql.*;
public class test4 {
public static void main(String args[]) {
String url_String
= "jdbc:oracle:thin:test/test@myhost:1521:myorcl";
try {
Class.forName
("oracle.jdbc.driver.OracleDriver");
java.sql.Connection con =
java.sql.DriverManager.getConnection(url_String);
con.setAutoCommit(true);
Statement stmt
=con.createStatement();
String sqlStr ="insert into
clob1 (mclob) " + "values(empty_clob())";
stmt.executeUpdate(sqlStr);
String query = "select
test_seq.CURRVAL from dual";
ResultSet rs =stmt.executeQuery
(query);
rs.next();
int currval =rs.getInt(1);
query = "select * from clob1 where
id="+currval;
String str
="abcedefhijklmnopqrstuvwxyz";
rs =stmt.executeQuery(query);
rs.next();
java.sql.Clob clob1
=rs.getClob(2);
oracle.sql.CLOB clob=
(oracle.sql.CLOB)clob1;
System.out.print(clob);
java.io.Writer
wr=clob.getCharacterOutputStream();
wr.write(str);
wr.flush();
wr.close();
stmt.close();
con.close();
} catch(Exception ex) {
System.err.println("SQLException: "
+ ex.getMessage());
null

Answer 1

Hi,
To avoid ORA-22920 error while selecting lob column, use the 'for update' clause in the select statement like :
query = "select * from clob1 where id="+currval+" FOR UPDATE" ;
This should solve the problem. However, after fixing this, you might get the error :
java.sql.SQLException: ORA-1002: fetch out of sequence
I got this error when testing your code. To avoid this error, before executing 'select ... for update' statement Set AutoCommit to OFF, like :
query = "select * from clob1 where id="+currval+" FOR UPDATE" ;
con.setAutoCommit(false);
rs =stmt.executeQuery(query);
Hope that Helps,
Srinivas