I have written a script which will fetch data from db with certain condition and store it in the hash. I need these stored hash content to show in the tabular format. Right now I have all the data which should be shown in the table is there in the hash called %hash.

I need to display the content of the hash in console in tabular format.

Below is my script:

#!/usr/bin/perl

use strict; use warnings;
use Data::Dumper;

my %hash = (
  '2022-08-04' => {
      'Method 1' => {
            'Count' => 50,
            'Size' => '10 MB'
      },
      'Method 2' => {
            'Count' => 40,
            'Size' => '5 MB'
      }
  },
  '2022-08-05' => {
      'Method 1' => {
            'Count' => 30,
            'Size' => '3 MB'
      },
      'Method 2' => {
            'Size' => '50 MB',
            'Count' => '100'
      }
  }
);

my @cols;
my @keys = ('Method 1', 'Method 2');

foreach my $date (sort keys %hash){
    foreach my $method (@keys) {
    push (@recs, { date => $date, size => $hash{$date}{$method}{'Size'}, count => $hash{$date}{$method}{'Count'}});
    }
}

print "cols:\n".Dumper(\@cols)."\n";

my $line1 = '| ' . join(' | ', map { sprintf "%-*s", 20, $_->{date} } @cols) . ' |';
my $line2 = '| ' . join(' | ', map { sprintf "%-*s", 20, $_->{size} } @cols) . ' |';
my $line3 = '| ' . join(' | ', map { sprintf "%-*s", 20, $_->{count} } @cols) . ' |';

print $line1."\n";
print $line2."\n";
print $line3."\n";

Current Result:

| 2022-08-04           | 2022-08-04           | 2022-08-05           | 2022-08-05           |
| 10 MB                | 5 MB                 | 3 MB                 | 50 MB                |
| 50                   | 40                   | 30                   | 100                  |

Expected Result:

-----------------------------------------------------------------------------------
| Date          | Method 1 Size | Method 1 Count | Method 2 Size | Method 2 Count |
-----------------------------------------------------------------------------------
| 2022-08-04    | 10 MB         | 50             | 5 MB          | 40             |
| 2022-08-05    | 3 MB          | 30             | 50 MB         | 100            |
-----------------------------------------------------------------------------------

Since the data I'm pushing into @cols, each of the cols array element contains a hash with date, size and count. And while printing them it shows in horizontal way instead of showing it in vertically.

Also, sometimes there wouldn't be Method 2 hash values. In that scenario I need to display content of Method 1 hash values in table alone. How to achieve it in dynamic way?

CodePudding user response：

You have an outer loop over the fields (the copy and pasted lines), and an inner loop over the flattened records.

But the desired output shows a loop over the dates wrapping a loop over the methods wrapping a loop over the fields.

(Click to enlarge to get a better view.)

{
   printf "| %-*s | ", 20, "Date";

   for my $method ( "Method 1", "Method 2" ) {
      printf "%-*s | %-*s |",
         20, "$method Size",
         20, "$method Count",
   }

   printf "\n";
}

for my $date ( sort keys( %hash ) ) {
   my $by_method = $hash{ $date };

   printf "| %-*s | ", $date;

   for my $method ( "Method 1", "Method 2" ) {
      my $rec = $by_method->{ $method };

      printf "%-*s | %-*s |",
         20, $rec->{ size  },
         20, $rec->{ count };
   }

   printf "\n";
}

There's a lot of magic numbers in there.

my @methods = ( "Method 1", "Method 2" );

my $date_size = 20;

my @field_defs = (
   { name => "Size",  size => 20 },
   { name => "Count", size => 20 },
);

{
   printf "| %-*s | ", $date_size, "Date";

   for my $method ( @methods ) {
      for my $field_def ( @field_defs ) {
         printf "%-*s |", $field_def->{ size }, $field_def->{ name };
      }
   }

   printf "\n";
}

for my $date ( sort keys( %hash ) ) {
   my $by_method = $hash{ $date };

   printf "| %-*s | ", $date_size, $date;

   for my $method ( @methods ) {
      my $rec = $by_method->{ $method };

      for my $field_def ( @field_defs ) {
         printf "%-*s |", $field_def->{ size }, $rec->{ $field_def->{ name } };
      }
   }

   printf "\n";
}

The next step might be to calculate the minimum sizes instead of using 20.

CodePudding user response：

Added as a new answer, because i think both styles are worth. Like i said in my other answer. Do the transformation of data before-hand. Then create your table. Here is another way of data-transformation by flattening the inner-hash first.

#!/usr/bin/env perl
use strict;
use warnings;
use v5.32;
use Data::Printer;
use Text::Table;
use List::Util qw(uniqstr);

my %hash = (
  '2022-08-04' => {
      'Method 1' => {
            'Count' => 50,
            'Size' => '10 MB'
      },
      'Method 2' => {
            'Count' => 40,
            'Size' => '5 MB'
      }
  },
  '2022-08-05' => {
      'Method 1' => {
            'Count' => 30,
            'Size' => '3 MB'
      },
      'Method 2' => {
            'Size' => '50 MB',
            'Count' => '100'
      }
  }
);

# Transform %hash by flattening the inner hashes
my