I guess u've not...

To put your database in single user mode immediately, fire this.. Note that all incomplete transactions will be rolled back immediately.

ALTER DATABASE [yourDatabase]

SET SINGLE_USER WITH

ROLLBACK IMMEDIATE

If you wish to...

writing triggers on all tables would be little cumbersome and as said earlier would hit production.

You can also think of implementing log shipping. keep log backup interval relatively higher and...

If you're monitoring through enterprise manager, it does get into hung state when there is intensive IO activity.. you can see these activities and locks by querying syslocks and sysprocesses...

Thanks Jerry. My question gets answered in that link.

Also this statement looks confusing..

you're trying to update org_id in LOCATIONS table with uname ( i assume it's meant to store person's first name) from PERSON Table....

alter database DB_NAME set read_only

alter database set read_only