Well, if that's what you want, you can just make your query be: 
$rows_affected = $dbh->do("UPDATE meters SET description=? WHERE name=
+? and description <> ? ", undef, $info, $meter, $info);

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At least in other databases I'm familiar with, the "rows affected" means the rows that fit the where clause. It does not actually perform a diff against the old values, and only report the changes. 
------------
:Wq
Not an editor command: Wq

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In reply to Re: Odd "rows affected" values using DBI on MySQL by etcshadow
in thread Odd "rows affected" values using DBI on MySQL by LassiLantar

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