multiple keys hash with array as a value

grandagent has asked for the wisdom of the Perl Monks concerning the following question:

I have a hash which looks somewhat like this ( it has multiple keys for "connection-id" and "username"

$VAR1 = {
          'connection-id' => {
                       'username' => [
                                       value 1,
                                       value 2
                                     ],
                             }
....
}
[download]

What I want to do is loop through that hash and make a string comparison to "value 2" for each of the users but it only give me the first user in the hash, I don't understand why. Appreciate your feedback in advance. This is my loop

foreach my $connection (keys %h) {
        foreach my $userid (keys %{$h{$connection}}) {
                @a_ref = @{$h{$connection}{$userid}};

                        if(lc($userid) eq "rmdb_dbo") {
                            print @a_ref, if ( $a_ref[1] =~ m/update\s
+*[table\s*]rmdb_dbo./i );
                        }
        }
}
[download]

Comment on multiple keys hash with array as a value - loop Select or Download Code

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Re: multiple keys hash with array as a value - loop by Limbic~Region (Chancellor) on Dec 08, 2021 at 15:50 UTC
grandagent, You said "but it only give me the first user in the hash" when what you should have said is "it only produces output for user rmdb_dbo". That's because your if condition is only displaying output for that user. Try this to debug: `for my $connection (keys %h) { print "Looking at connection '$connection'\n"; for my $userid (keys %{$h{$connection}}) { print "\tLooking at userid '$userid'\n"; @a_ref = @{$h{$connection}{$userid}}; if(lc($userid) eq "rmdb_dbo") { print @a_ref, if ( $a_ref[1] =~ m/update\s[table\s]rmdb_ +dbo./i ); } else { print "Not checking '@a_ref' because user is not 'rmdb_dbo +'\n"; } } }` [download] Cheers - L~R	[reply] [d/l]
Re^2: multiple keys hash with array as a value - loop by grandagent (Novice) on Dec 08, 2021 at 20:13 UTC
My description was a bit confusing I admit. I just used "value1" "value2" as a placeholder. The acutall strings look like this: `value1 = UID="rmdb_dbo";DBN=234952;... value2 = update rmdb_dbo....` [download] where value2 can be also "insert/delete ..." and so on (any type of SQL statement) rmdb_dbo is the user that can have multiple connections i.e. multiple connection-id's for that particular user Cheers	[reply] [d/l]
Re: multiple keys hash with array as a value - loop by choroba (Cardinal) on Dec 08, 2021 at 15:50 UTC
The code snippets don't correspond to each other. `value 2` doesn't match `/update\s[table\s]rmdb_dbo./i'. Moreover, the string 'table` in the square brackets seems like a meaningful word, but square brackets introduce character classes, so `[table\s]` in fact matches a single character a, b, e, l, t, asterisk, or whitespace. Try to post runnable code like the following: `#!/usr/bin/perl use warnings; use strict; use feature qw{ say }; my %h = ( 'connection-id0' => { username1 => ['value 1', 'value 2'], username2 => [ 'value5' ], }, 'connection-id1' => { username1 => ['value 2', 'value 3'], }, 'connection-id2' => { username1 => ['value 3', 'value 4'], } ); for my $connection (keys %h) { foreach my $userid (keys %{ $h{$connection} }) { my @ar = @{ $h{$connection}{$userid} }; if (lc $userid eq 'username1') { say "@ar" if grep /value 2/i, @ar; } } }` [download] I used grep so the "value 2" might be located anywhere in the array. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]`	[reply] [d/l] [select]
Re^2: multiple keys hash with array as a value - loop by grandagent (Novice) on Dec 08, 2021 at 20:23 UTC
Thanks for the reply "value1/2" are not the acutal strings those are just placeholders. The string looks like this `value1="UID=rmdb_dbo;DBN=326474...."` [download] (UID can have different usernames, I just picked rmdb_dbo as an example but it can also be a personal user like "cb2ayal" for example) value2 can be any SQL string like the below `"update ..." "insert ..." "delete ..."` [download] I am insterest in the tables with "rmdb_dbo" so I need to grep for this string	[reply] [d/l] [select]
Re: multiple keys hash with array as a value - loop by LanX (Saint) on Dec 08, 2021 at 17:03 UTC
borrowing the data from choroba `use v5.12; use warnings; my $h = { 'connection-id0' => { username1 => ['value 1', 'value 2'], username2 => [ 'value5' ], }, 'connection-id1' => { username1 => ['value 2', 'value 3'], }, 'connection-id2' => { username1 => ['value 3', 'value 4'], } }; while ( my ( $con, $h_users) = each %$h ){ while ( my ($user, $a_vals) = each %$h_users ) { my $val = $a_vals->[1] // ""; say "Found $con -> $user -> $val" if $val =~ /value/; } }` [download] OUTPUT: `Found connection-id2 -> username1 -> value 4 Found connection-id1 -> username1 -> value 3 Found connection-id0 -> username1 -> value 2` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l] [select]
Re: multiple keys hash with array as a value - loop by AnomalousMonk (Archbishop) on Dec 09, 2021 at 03:35 UTC
And I'll bring up the rear again with the note that the Perl Data Structures Cookbook (perldsc) discusses the handling of complex data structures such as a Hash of a Hash of Arrays (HoHoA). Give a man a fish: `<%-{-{-{-<`	[reply] [d/l]


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multiple keys hash with array as a value - loop