This example will insert a string value of 'null', which likely isn't
what you want, nor a good idea.  Remove the quotes from null, and the
column default will instead be a null.  Example:

SQL> create table student (student_name varchar2(10) default null);

A null string and a null value are not the same thing, which you can see
using dump:

SQL> select dump(student_name) from student;

DUMP(STUDENT_NAME)
----------------------------
Typ=1 Len=4: 110,117,108,108  <-- null string
NULL <-- null value

I once worked with a developer who didn't understand the difference, and
inserted null strings instead.  It was a mess.

Suzy

"donald.holloway" wrote:
> 
> All,
> 
> I need to know if there is a way to insert a character value of 'null' as a
> default for a column:
> 
>   example:  student_name     varchar2(10) default 'null'
> 
> I have tried this and it works if I update the column values to the string
> 'null' later:
> 
>   example:  update student set student_name = 'null' where student_name is
> null
> 
> I know that null is a reserved word but I though that I saw it used
> somewhere like this before and just thought I would check with the group on
> this.  thanks.
> 
> Joseph Hway
> [EMAIL PROTECTED]
> 
> --
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> --
> Author: donald.holloway
>   INET: [EMAIL PROTECTED]
> 
> Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
> San Diego, California        -- Public Internet access / Mailing Lists
> --------------------------------------------------------------------
> To REMOVE yourself from this mailing list, send an E-Mail message
> to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
> the message BODY, include a line containing: UNSUB ORACLE-L
> (or the name of mailing list you want to be removed from).  You may
> also send the HELP command for other information (like subscribing).
-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Suzy Vordos
  INET: [EMAIL PROTECTED]

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).

Reply via email to