my $from_datestring = sprintf '%04d-%02d-%02d', ($cgiparams{"FROM_YEAR"}, $cgiparams{"FROM_MONTH"}, $cgiparams{"FROM_DAY"});
my $to_datestring = sprintf '%04d-%02d-%02d', ($cgiparams{"TO_YEAR"}, $cgiparams{"TO_MONTH"}, $cgiparams{"TO_DAY"});
+# Check if the to datestring is later than the from datestring.
+unless ($to_datestring ge $from_datestring) {
+ $errormessage = "$Lang::tr{'error the to date has to be later than the from date'}";
+}
+
my $database_query = qq(
SELECT
common_name, SUM(