For the moment I don't use fetchall_arrayref (even it is a better solution) because some strange errors concerning the validity of my SQL occurs. anyway I am trying to build my structure. 
@structure = (
    [{ ... },
    ],
    [
        { ... },
        { ... },
    ],
    [
        { ... },
        { ... },
    ],
    [
        { ... },
        { ... },
    ],
);

##

foreach @query {
  my @ex = executeRequest ($_);
  push @structure, [];
for (my $i=0;$i<=$#ex;$i++) {
            
   push @structure->[$i], $ex[$i]; 
            
}

[download]
and I got this message:
Type of arg 1 to push must be array (not array element) at service.pm line 152, near "];"
I am a bit confusing with some notation of references and I think I don't interpret properly @results->[$i]. is there another one (except @results[$i]) ?
by the way, the sum function seems very interesting and I tested it. 
my @structure = (
   [ # Result from first query.
    {
     'field1_statement1' => 'value',
     'field2_statement1' => 'value'
    },
      
   ], 
   [ #Results from second query 
       
    {
     'field1_statement2' => 'value',
         'field2_statement2' => 'value',
         'field3_statement2' => 'value'
    },
    {
      'field1_statement2' => 'value',
          'field2_statement2' => 'value',
          'field3_statement2' => 'value'
    }
             
    ],
    [ # results from third query
     
         { 'field1_statement2' => 'value' } 
    ]
);

my $q2Total = sum @{ $structure[ 1 ] };
print $q2Total."\n";

[download]
and the results is ... 277446212

I do think I missed something :)
Sorry for these naive questions.

In reply to Re^6: Best complex structure? by mat21
in thread Best complex structure? by Anonymous Monk

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