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copied!<p>Why don't you test your changing columns by using <code>IF UPDATE(Column1,Column2,...)</code> That will let you know whether any of the columns have changed that you're interested in. See <a href="http://msdn.microsoft.com/en-us/library/ms187326.aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/ms187326.aspx</a> for details on the <code>UPDATE()</code> function.</p> <p>You'll also be able to use it if the PK has been modified, whereas comparing between the <code>inserted</code> and <code>deleted</code> the way you're trying to go about it will miss out on changes to the PK.</p> <p>The solution involving testing the inequality of all of the fields will fail unless you <code>SET ANSI_NULLS OFF</code> before comparing.</p> <p>For example:</p> <pre><code>create table table1 ( a varchar(4), b varchar(4) null) create table table2 ( a varchar(4), b varchar(4) null) go insert into table1 ( a, b ) select 'asdf', null insert into table2 ( a, b ) select 'asdf', 'zzzz' --Expect no results select * from table1 inner join table2 on a.a = b.a where a.b <> b.b set ansi_nulls off --Expect 1 result select * from table1 inner join table2 on a.a = b.a where a.b <> b.b </code></pre> <p>Of course, you could put in additional tests rather than going with the <code>ansi_nulls</code> option, but that gets particularly crazy if you're doing this with many fields. Also: you must <code>set ansi_nulls off</code> prior to creating the trigger - you can't turn it on and off inside the trigger, so the whole thing must have the same <code>ansi_nulls</code> setting.</p>

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