Just a couple of other points.

Your statement handle would benefit from placeholders, and forming a closure for the prepared handle would allow the prepare call to only be done once: 

# after $dbh is obtained
{
    my $sth = $dbh->prepare
        "select
            hall_name,
            upload_date,
            uploaded_by,
            photo_id
        from hall_details
        where
            hall_id=?
            limit 1";

    sub details_from_id {
        my $id = shift;
        $sth->execute $id;
        $sth->fetchrow_hashref;
    }   # mod some error checking
}

[download]
With that, you get the the advantages of global variables without some of the headaches. The DBI handle could itself be encapsulated this way. Is hall_id the primary key? If so the limit clause can be omitted.

The other point is that your returned hash is a level too deep. The caller already knows $hall_id - it was passed as an argument - and will just need to extract the lone value from your return. With that, you can just call details_from_id directly. 

my @hall_ids = 1..20;
my %details;
@details{@hall_ids} = map { details_from_id $_ } @hall_ids;

[download]

After Compline,
Zaxo

In reply to Re: Making hashes from arrays by Zaxo
in thread Making hashes from arrays by CodeJunkie

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