Converting LONG to CLOB

I want to convert a column from LONG to CLOB but I get an error:

ORA-22858: invalid alteration of datatype

I'm using Oracle 8.1.7 under Linux.

This is what I'm doing:

ALTER TABLE mytable MODIFY (longfield CLOB);

and the table is:

CREATE TABLE mytable(ID int, longfield LONG);

Then I tried creating a new column of type CLOB and attempted to copy the LONG into it but get the error:

ORA-00932: inconsistent datatypes

Here's what I'm doing:

UPDATE mytable SET clobfield = TO_LOB(longfield )

Can anyone help me out with these problems? Thanks. Received on Wed Dec 04 2002 - 05:33:22 CST