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From "Mamta Satoor" <msat...@gmail.com>
Subject Re: Foreign key -- implicit index?
Date Sun, 18 Mar 2007 04:08:33 GMT
Yes, that is correct. Copied following from the CREATE INDEX page in Derby's
documentation
Unique, primary key, and foreign key constraints generate indexes that
enforce or "back" the constraint (and are thus sometimes called *backing
indexes*).

Mamta

On 3/17/07, Dan Karp <dkarp@zimbra.com> wrote:
>
> Just to make sure, this foreign key declaration
>
>   CONSTRAINT fk_mail_item_parent_id FOREIGN KEY (mailbox_id, parent_id)
>     REFERENCES ${DATABASE_NAME}.mail_item(mailbox_id, id),
>
> implicitly creates an index on (mailbox_id, parent_id), right?
>

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