For example:

eval{$db = DBI->connect("DBI:ODBC:$config{db_odbc}", $config{db_user},
+ $config{db_pass}, {PrintError=>0, RaiseError=>1, AutoCommit=>0})};

error("Could not connect to database:", map{" DBI: $_"} split /\n/, $D
+BI::errstr) if $@;
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In this example, error() is a custom function to print/log errors.