Re: cascade delete - Mailing list pgsql-jdbc

But the image table is the master table where all the entires on image is
done.

The accomm_images table has mapping of accomm_id and images.

Now I want to delete images of a accomm_id. So I delete records from
accomm_images table based on that accomm_id and want the images to be delted
from image table.

-----Original Message-----
From: Andrew Rawnsley [mailto:ronz@ravensfield.com]
Sent: 16 February 2004 15:58
To: Bhushan Bhangale
Cc: pgsql-jdbc@postgresql.org
Subject: Re: [JDBC] cascade delete



If I am understanding properly  what you want, you have your
referential integrity backwards.
If you want everything from table image to be removed when you execute
'delete from accomm_images' your
table definition should be:

> CREATE TABLE accomm_images(
>     accomm_id            int4 NOT NULL references accomm(id),
>     image_id             int4 NOT NULL
> );

> CREATE TABLE image(
>     id             int4 NOT NULL references accomm_images(image_id) on

> delete cascade,
>     url             int4 NOT NULL
> );

The reference goes from child to parent, not parent to child, and from
what you say the image table is the child
and accomm_images is the parent.

On Feb 16, 2004, at 9:49 AM, Bhushan Bhangale wrote:

> Hi,
>
> I have following 2 tables in postgres DB. I created a cascade delete
> constraint on image_id column of accomm_images which is a foreign key
> from
> image tbale.
>
> When I execute -> delete from accomm_images
> It should delete all the child records of image table as well. But its
> not
> happening.
>
> CREATE TABLE image(
>     id             int4 NOT NULL,
>     url             int4 NOT NULL
> );
>
> CREATE TABLE accomm_images(
>     accomm_id            int4 NOT NULL references accomm(id),
>     image_id             int4 NOT NULL references image(id) on delete
> cascade
> );
>
>
> Is there anything missing?
>
> Thanks
> Bhushan
>
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--------------------

Andrew Rawnsley
President
The Ravensfield Digital Resource Group, Ltd.
(740) 587-0114
www.ravensfield.com


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