eval{} is a general solition but is not needed in this case becaue DBI handles have two modes for reporting errors depending on the state of the RaiseError attribute.

If $dbh->{RaiseError} is false (the default) then you can ignore SQL errors simply by not checking to see if there's been one.

Personsally I always open DBI handles with RaiseError true and switch it off locally in blocks where I want to ignore or recover from SQL errors.

To drop an SQL object that may or may not exist I do:

{
    local $dbh->{RaiseError} = 0;
    $dbh->do("drop table DSR_SMR_Result_storage_keep");
}
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Obviously if the drop fails for some reason other than the object not existing then I miss the reason but since the next SQL statment is typically about to create the object again I do at least get an error there.