Re: Thanks, but... [2]

From: DA Morgan <damorgan_at_x.washington.edu>
Date: Fri, 28 Jan 2005 17:11:08 -0800
Message-ID: <1106960916.501248@yasure>

Piotr B. wrote:

> Mark D Powell wrote:
>

>> it may also be of interest that all_, dba_, and user_tab_columns

>
> > contain a column named NULLABLE that can be used to
>

>> determine the NULL allowed status of a column.

>
>
> Yes, I mentioned this fact in my first post:
> > the information is already stored in user_tab_columns.nullable
>
> Unfortunately, my problem remains unsolved. I want to write some
> application to export database schema from Oracle, and I don't
> see an easy way to distinguish "real", user-added check constraints
> (like "GENDER IN ('M', 'F')") from automatically generated and
> redundant "column IS NOT NULL" constraints for every non-null column.
>
> Creating PL/SQL procedures/function to cast
> user_constraints.search_condition to varchar2 in order to apply
> "NOT LIKE '% IS NOT NULL'" is not possible when you have read-only
> access to the database...

What is the point of this exercise? There is not a bit of difference between a NOT NULL and a NOT NULL.

-- 
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace 'x' with 'u' to respond)

Received on Fri Jan 28 2005 - 19:11:08 CST