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copied!<p>Your trigger is an "AFTER" trigger (the default) rather than "INSTEAD OF". With an AFTER trigger, the "deed has been done" already--i.e., the insert into DeletedUser has already occurred, so you do <em>not</em> need the INSERT statement.</p> <p>The foreign key relationship between DeletedUser and UserLogin is just all wrong. These tables are, from what you have described, <em>mutually exclusive</em>: having a user in DeletedUser means they should no longer be in UserLogin, and having the user in UserLogin means they wouldn't also be a DeletedUser.</p> <p>So, remove the foreign key relationship, and try this:</p> <pre><code>CREATE TRIGGER trgInsert_ToDeleteFromUserLogin on DELETEDUSER FOR INSERT AS BEGIN DELETE FROM UserLogin WHERE EXISTS (SELECT NULL FROM INSERTED WHERE INSERTED.USERNAME = UserLogin.USERNAME) END </code></pre> <p>Edit: As Shannon mentioned below, this code will properly handle situations where multiple records are inserted at the same time, in contrast to the single-row assumption of the original code. The use case (disabling a user) suggested only a single insert at a time, but it's better (and easier) to built triggers to operate against the entire set of records in the inserted/deleted metatables.</p> <p>As an aside, your database design could be simplified by using views. Example:</p> <pre><code>ALTER TABLE UserLogin ADD DeletedReason varchar(255) NULL CREATE VIEW ActiveUser AS SELECT * FROM UserLogin WHERE DeletedReason IS NULL </code></pre>

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