the if... else can be expressed a bit more elegantly: 
@{$HashRef->{$ItemId}} ||= [];
push @{$HashRef->{$ItemId}}, $DataSource;

[download]
apart from that: the notation of variable names you chose is not perlish. in perl you mix capital and small letters only for class names: package MyClass; vs:  my $hash_ref;

language is a virus from outer space.

In reply to Re: Complex Data Structure Suggestions Wanted by thcsoft
in thread Complex Data Structure Suggestions Wanted by Ninthwave

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