Why does DBI programming tend to use references to arrays and hashes, rather than just straight arrays and hashes?

Not that it makes a huge difference, but why is the default style of programming 

while(my $ref = $sth->fetchrow_hashref() ){
    ## do something with $ref
}

[download]
rather than 
while(my %hash = $sth->fetchrow_hash() ){
    ## do something with %hash
}

[download]

I'm just trying to puzzle out if there's any advantage.

Bonus question -- why is there a fetchall_arrayref() but not a simple fetchall_array()?

I can see why there isn't a fetchall_hash, because of clobbering, but fetchall_array() would have been perfect for a bit of code I just wrote, because I wanted to do a join() on it. As it was I had to add an extra step in the code.

Nobody says perl looks like line-noise any more
kids today don't know what line-noise IS ...

In reply to Why a reference, not a hash/array? by Cody Pendant

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