Cascade delete question

[Glenn MacGregor]

Hi All,

Sorry if this is a double post.

Here is an example of my table which works

vid vname parentname
1 ***@test.com
2 ***@test.com ***@test.com
3 ***@test.com ***@test.com
4 ***@test.com ***@test.com
5 ***@test.com ***@test.com

So my simple cascade on delete states that if I delete a row whose vname
matches the parentname of any other delete those rows.

No problem this works great!

Now I have changed my data to

vid vname parentname
1 ***@test.com
2 ***@test.com n1
3 ***@test.com n1
4 ***@test.com n1
5 ***@test.com n3

Notice the parentname is a substring of the vname. I can get that
substring from a select query

select (substring(vname from 0 for position('@' in vname)) from table1

This query returns
vname
------
n1
n2
n3
n4
n5

Can I change my delete cascade constraint to do this substring query
instead of an exact match?

Is there anyway to accomplish what I need to do?

Thanks

Glenn MacGregor



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[Bruno Wolff III]

On Thu, Apr 22, 2004 at 16:46:31 -0400,

Post by Glenn MacGregor
No problem this works great!
Now I have changed my data to
vid vname parentname
Can I change my delete cascade constraint to do this substring query
instead of an exact match?

No.

Post by Glenn MacGregor
Is there anyway to accomplish what I need to do?

If the local part of the email address is a candidate key, separate it
from the domain name and make it the primary key.

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