Array of Arrays from DB

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hello:

I have what seemed like a simple problem at first, but I cannot get my code to work. Basically, I have a simple SQL SELECT statement (which returns only 3 fields) I am performing on a MySQL database using DBI and DBD::mysql. I want to do a fetchrow_array, then take each returned row and push it into a multidimensional array. What it looks like the code below gets me is an array of arrays with the correct number of elements from the SELECT statement, but the @drivers array I am pushing into contains the arrays with no data. To make sure I am getting the data out of the database properly, I can print the @arr and return the expected data. Am I missing something obvious here, or am I just going about this all wrong? Is there a better way to return db results into an array of arrays?

Thanks, and btw, this is by far the most helpful perl resource on the web.

# build multidimensional array from results
while (@arr = $sel->fetchrow_array) {
    push (@drivers, \@arr);
    # prints the correct data from the db
    print "arr: @arr\n";
}

# prints the right number of ref's    
print @drivers;
    
# this just prints the commas and the spaces
foreach my $item (@drivers) {
print "$item->[0], $item->[1], $item->[2]";
}
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Comment on Array of Arrays from DB Download Code

Replies are listed 'Best First'.

•Re: Array of Arrays from DB
by merlyn (Sage) on May 30, 2002 at 19:35 UTC

my column on "deep copying"

-- Randal L. Schwartz, Perl hacker

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Re: •Re: Array of Arrays from DB

by Anonymous Monk on May 30, 2002 at 21:57 UTC

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Re: Array of Arrays from DB
by abaxaba (Hermit) on May 30, 2002 at 20:40 UTC

push

    my $rows = $sel->fetchall_arrayref();
    
    # still prints the right number of refs 
    print @$rows;
    

    foreach my $row (@$rows)
    {
        print join (",", @$row)
    }
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ÅßÅ×ÅßÅ
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Re: Array of Arrays from DB
by fenonn (Chaplain) on May 30, 2002 at 20:43 UTC

my $sth = $dbh->prepare( 'SELECT * FROM tbl');
$sth->execute()
my $arrayRef = $sth->fetchall_arrayref([]);
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