In addition to what bv explained, the $sth->fetchrow may also fail. From the docs (emphasis added):

If there are no more rows or if an error occurs, then fetchrow_array returns an empty list. You should check $sth->err afterwards (or use the RaiseError attribute) to discover if the empty list returned was due to an error.

In reply to Re: MSSQL and Perl - heavy load by almut
in thread MSSQL and Perl - heavy load by taomanjay

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