There's a definite advantage - speed. If you use this version: %hash = $sth->fetchrow_hash(), Perl will have to fetch the whole row and stuff it into the hash. If the row happens to have 100 cols and 50 of them have 1meg of data, it will (usually) be much slower than grabbing a ref and getting only what is needed when it is needed.

Your bonus question is directly related. To implement fetchall_array(), it'd have to slurp the entire table just to stuff it into your @array.

Not terribly efficient. If you really want to do that, they make you write it yourself. One fairly easy way would be to copy the deref'd array ref into a new array: 

@data = @{$sth->fetchall_arrayref()};

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In reply to Re: Why a reference, not a hash/array? by dynamo
in thread Why a reference, not a hash/array? by Cody Pendant

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