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Home -> Community -> Usenet -> c.d.o.server -> Re: Change from Long to Varchar2(2000)
Cyrus AU YEUNG wrote:
>
> Dear all experts,
>
> I want to alter the datatype of a column from 'LONG' to
> 'VARCHAR2(2000)'. But when I issue the following sql,
>
> alter table mytable modify (mycolumn varchar2(2000));
>
> The following error occurs,
> ORA-01439: column to be modified must be empty to change datatype
>
> In my case, I cannot update all the non-null column to null and then
> alter the table since it is very large. Can anyone give me a helping hand?
>
> Thanks!!
>
> Cyrus
How large is large. I think that it is a truism that the column must be
empty to change data type. changing length ok. (say varchar2(100) to
varchar2(1000). Im wondering about the performance you get with a
varchar2(2000) as one of the columns. Specially if it is a large table.
Received on Thu Mar 12 1998 - 00:00:00 CST