Re: Enforcing uniqueness of data
Re: Enforcing uniqueness of data
- Subject: Re: Enforcing uniqueness of data
- From: Kieran Kelleher <email@hidden>
- Date: Wed, 7 Sep 2005 15:08:50 -0400
Put a UNIQUE INDEX on the login field in the database table and then
handle the error when changes are saved (try - catch). You will get a
general adaptor exception which you need to examine and check that the
error is caused by trying to insert a row which violates the unique
key. This technique is useful and can also be used for unique
combinations of attributes.
On Sep 7, 2005, at 1:00 PM, Daniel Eggert wrote:
I need the login of my user EO to be unique. Since the login is
something the user enters, it is not the PK.
How would I go about ensuring this? If I fetch from the database and
then write if it is unique, someone might be able to write to the
database in the meantime.
This post
<http://lists.apple.com/archives/webobjects-dev/2004/Jun/
msg00249.html>
suggests locking. Is it a sane approach? How would I do such a thing
with EOF?
Thanks in advance.
/Daniel
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Webobjects-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
email@hidden
This email sent to email@hidden
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Webobjects-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden