from memory what you get is a hashref to the hash holding the result of your query. hence first you need to dereference the initial hashref. so something like this during your fetch processing loop: 
my $column1value = \$result_hash{'col1'};

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note the back slash, dereferencing the hash reference. there are examples of fetch loop processing code using the fetchall_hashref on the web and in the documentation for DBI.
the hardest line to type correctly is: stty erase ^H

In reply to Re: can't use string as hash ref by aquarium
in thread can't use string as hash ref by spickles

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