In summary. This bit of code gives:

    while ( my @col_col = $sthZK_Update_extract->fetchrow() ) {
    
      my $Key_m = $col_col[0];
      my $Cause = $col_col[1];
      my $Aggregated_area = $col_col[2];
      my $SUM_wixi = $col_col[3];
      my $SUM_wi = $col_col[4];
      my $SUM_xi = $col_col[5];
      my $SUM_ni = $col_col[6];
      my $Sum_wi2xi = $col_col[7];
    
      print "\n^^^^^^\n$Key_m, $Aggregated_area, $Cause, $SUM_wixi, $S
+UM_wi, $SUM_xi, $SUM_ni, $Sum_wi2xi\n";
    
    }
    
    my $numerator_L = 2*($SUM_ni-$SUM_xi);     
    my $denominator_L = 2*$SUM_xi;             

    my $numerator_U = 2*($SUM_xi+2);           
    my $denominator_U = 2*($SUM_ni-$SUM_xi);
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Gives:

^^^^^^
1, All, Circulatory_Disease, 2.1323785396701751E-4, 4.4283294159368431
+E-6, 1376,
 4224420, 3.3947194253425559E-11
Use of uninitialized value in subtraction (-) at Creating_table_ZZI_Pa
+ul.pl line
 1210.
Use of uninitialized value in subtraction (-) at Creating_table_ZZI_Pa
+ul.pl line
 1210.
Use of uninitialized value in multiplication (*) at Creating_table_ZZI
+_Paul.pl l
ine 1211.
Use of uninitialized value in addition (+) at Creating_table_ZZI_Paul.
+pl line 12
16.
Use of uninitialized value in subtraction (-) at Creating_table_ZZI_Pa
+ul.pl line
 1217.
Use of uninitialized value in subtraction (-) at Creating_table_ZZI_Pa
+ul.pl line
 1217.
Invalid n: 0
[download]