SQL Server Update trigger for bulk updates - sql

Question

Below is a SQL Server 2005 update trigger. For every update on the email_subscriberList table where the isActive flag changes we insert an audit record into the email_Events table. This works fine for single updates but for bulk updates only the last updated row is recorded. How do I convert the below code to perform an insert for every row updated?
CREATE TRIGGER [dbo].[Email_SubscriberList_UpdateEmailEventsForUpdate_TRG]
ON [dbo].[Email_subscriberList]
FOR UPDATE
AS
DECLARE #CustomerId int
DECLARE #internalId int
DECLARE #oldIsActive bit
DECLARE #newIsActive bit
DECLARE #email_address varchar(255)
DECLARE #mailinglist_name varchar(255)
DECLARE #email_event_type varchar(1)
SELECT #oldIsActive = isActive from Deleted
SELECT #newIsActive = isActive from Inserted
IF #oldIsActive <> #newIsActive
BEGIN
IF #newIsActive = 1
BEGIN
SELECT #email_event_type = 'S'
END
ELSE
BEGIN
SELECT #email_event_type = 'U'
END
SELECT #CustomerId = customerid from Inserted
SELECT #internalId = internalId from Inserted
SELECT #email_address = (select email from customer where customerid = #CustomerId)
SELECT #mailinglist_name = (select listDescription from Email_lists where internalId = #internalId)
INSERT INTO Email_Events
(mailshot_id, date, email_address, email_event_type, mailinglist_name)
VALUES
(#internalId, getDate(), #email_address, #email_event_type,#mailinglist_name)
END

Answer 1

example
untested
CREATE TRIGGER [dbo].[Email_SubscriberList_UpdateEmailEventsForUpdate_TRG]
ON [dbo].[Email_subscriberList]
FOR UPDATE
AS
INSERT INTO Email_Events
(mailshot_id, date, email_address, email_event_type, mailinglist_name)
SELECT i.internalId,getDate(),c.email,
case i.isActive when 1 then 'S' else 'U' end,e.listDescription
from Inserted i
join deleted d on i.customerid = d.customerid
and i.isActive <> d.isActive
join customer c on i.customerid = c.customerid
join Email_lists e on e.internalId = i.internalId

Answer 2

Left outer joins, for in case there are no related entries in customer or email_Lists (as is possible in the current code) -- make them inner joins if you know there will be data present (i.e. foreign keys are in place).
CREATE TRIGGER [dbo].[Email_SubscriberList_UpdateEmailEventsForUpdate_TRG]
ON [dbo].[Email_subscriberList]
FOR UPDATE
AS
INSERT INTO Email_Events
(mailshot_id, date, email_address, email_event_type, mailinglist_name)
select
i.InternalId
,getdate()
,cu.Email
,case i.IsaActive
when 1 then 'S'
else 'U'
end
,el.ListDescription
from inserted i
inner join deleted d
on i.CustomerId = d.CustomerId
and i.IsActive <> d.IsActive
left outer join Customer cu
on cu.CustomerId = i.CustomerId
left outer join Email_Lists el
on el.InternalId = i.InternalId
Test it well, especially for concurrency issues. Those joins within the trigger make me nervous.