See, how data structure in Perl works. It will be helpful a lot.
What you have is. 
my %hash = $AoH[0];
print keys %hash;

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You can just combine these too. 
print keys %hash 
=  print keys %{ hash }  
=  print keys %{ $AoH[0] }

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In reply to Re: Extract keys from an Array of Hashes by aartist
in thread Extract keys from an Array of Hashes by bradcathey

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