Could you clarify:

• You refer to the item as a hash of arrays when it appears to be a hash of array names.
• What is the point of having a seperate array of arrays for each key? Why not have a hash of an array of arrays? $HoA{$key}-[$sth->fetch()]

Any hoo..

• To access the first element of an array with the name given by $HoA{$key} which refers to an array of arrays:${$HoA{$l}}[0]->[0];
• The method to reference the hash of arrays is $HoA{$key}->[0]

My chance to waggle my finger and be boring

• In SQL: rows even in sequence only have an arbitrary value in a hash, unless you're using a field as the key.
• $aref is an array reference to an array of arrays (rows x fields) since fetch is an alias for fetchrow_arrayref, so why dereferencing it? It's make sense if there are more rows in the SQL being returned than you need, however this is wasteful - rewrite the SQL.

--

Brother Frankus.

Me: Curse you buckaduck for writing so tersely, I repeated your erm.. stuff and made me look dumb.
Brain: You made yourself look dumb.
Me: You mean I'm really good at something? Woo hoo!!