Kevin,
I don't think so. Here is what happens with a 8.1.7 database.
SQL> create table t (ca varchar2(2) not null, cb number);
Table created.
SQL> insert into t values ('AA', 1);
1 row created.
SQL> commit;
Commit complete.
SQL> desc t
Name Null? Type
----------------------------------------- --------
----------------------------
CA NOT NULL VARCHAR2(2)
CB NUMBER
SQL> select * from t;
CA CB
-- ---------------
AA 1
SQL> alter table t modify (ca null);
Table altered.
SQL> desc t
Name Null? Type
----------------------------------------- --------
----------------------------
CA VARCHAR2(2)
CB NUMBER
SQL> select * from t;
CA CB
-- ---------------
AA 1
SQL>
If the column 'CA' were to have a primary key constraint, then the
constraint needs to be dropped to modify the column as a nullable column.
Regards,
- Kirti Deshpande
Verizon Information Services
http://www.superpages.com
> -----Original Message-----
> From: Kevin Kostyszyn [SMTP:[EMAIL PROTECTED]]
> Sent: Wednesday, May 23, 2001 4:57 PM
> To: Multiple recipients of list ORACLE-L
> Subject: RE: Drop 'NOT NULL' Constraint
>
> I think that if there is already data in the column you will not be able
> to
> do that.
>
> -----Original Message-----
> Sent: Wednesday, May 23, 2001 5:15 PM
> To: Multiple recipients of list ORACLE-L
>
>
> I created a table with a 'NOT NULL' constraint on a VARCHAR2 column. I
> would like to remove the NOT NULL constraint. I've tried a couple of
> 'ALTER TABLE' commands but no luck.
>
> How does one do this?
>
> Also:
>
> How does one figure out which generated constraints (from
> user_constraints) do what?
>
> Chris Rezek
> Database Administrator
> DotClick
> http://www.dotclick.com
> --
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> --
> Author: Chris Rezek
> INET: [EMAIL PROTECTED]
>
>
--
Please see the official ORACLE-L FAQ: http://www.orafaq.com
--
Author: Deshpande, Kirti
INET: [EMAIL PROTECTED]
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