my @all_queries = (
    {'foo' => 20},
    {'bar' => 30},
    {'foo' => 10},
    {'zen' => 90},
    {'zen' => 1},
);

my %hash;

push @{$hash{(keys %$_)[0]}}, (values %$_)[0] foreach (@all_queries);

foreach my $key (keys %hash) {
    print "$key has " . join(',', @{$hash{$key}}) . "\n";
}
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