Or try MySQL, though you'll have to do the report writing yourself, though having SQL will do half the work.

Or, depending on what platform you're on, you might be able to use DBI::SQLite for a Perl-only database.

So what you have is two tables and you want to combine the data. This is the sort of task that a relational database excels at. If you were to store your data in one you could then use SQL to pull the values out in any format you want using syntax like this:

my $sql = 'SELECT student_id, grade, instructor 
           FROM student_info_table 
           WHERE class = ? 
           ORDER BY student_id';

my $sth = $dbh->prepare_cached($sql);
$sth->execute('BUS4000');

while ( @row = $sth->fetchrow_array ) {
    my ( $id, $grade, $instructor ) = @row;
    # blah
}
[download]

This lets you pull whatever you like out of a single table but the true power comes when you JOIN tables together so that you can pull results out of several tables at once. As you can see databases have inbuilt ORDER BY (sort) functionality as well. You will not regret it in the long run. Converting from your flat files to a database table can be done in around a dozen lines of perl.

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

• How do I sort an array by (anything)?
• sort
• Schwartzian transform
• Super Search *sigh*

- Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

Pick one tabulation to do first, load and manipulate the data to solve that tabulation. Keep it simple, and just think a little about how you'll need to re-use the data in the next tabulation.

Now pick the next tabulation to do. The data is already loaded and manageable, and the plan for this tabulation will dictate how you need to re-shuffle the data. Do that, then move on to the next tabulation.

If you keep the primary data in a somewhat minimalist structure, it will be easier to compartmentalize each distinct tabulation, pass the basic data to each compartment for that flavor of output, and add more tabulations / compartments to the code as you need to.

It's okay for the code to grow incrementally in this fashion. In some (most?) cases, coding the next tabulation will seem easier if you make up additional structures (keeping each one relatively simple) during the initial data read loops. Having three or four distinct HoA and/or HoH to feed four or five tables will get you finished more easily than one or two HoHoA, HoAoHoA or whatever -- especially if you design your simpler data structures the same way you would design a good RDB schema, e.g. one hash keyed by ssn to store "name, major,status", then a HoA keyed by course-id that stores lists of ssn's in each course, and so on.

foreach $item (sort @items) {
        @tmp= split (/!/, $item, 16);
        push (@test, @tmp);
        push @AoA, [ @tmp ];
}


print "\n";
# Print the whole thing, one at a time.
print "COMP7650 :\n";
print "_____________________\n";

for $i (0..$#AoA) {
print "$class{$AoA[$i][0]} \n\t $student{$AoA[$i][0]}\n";
        for $j (0..$#{ $AoA[$i] }) {
                if ($j eq 1) {
                        print "\t\t\t- $AoA[$i][1]\n";
                }
        }
}
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In the above code i made an Array of array which holds the values from the student-information file.
I also made a a hash for each of the items i want from the student-file. somehing like so:

open (FILE, "student.data");
while (defined ($line = <FILE>)) {
        if ($line =~ /^(.*)!(.*)!(.*)!(.*)$/) {
                $id{$1}      = $1;   #id's
                $student{$1} = $2;
                $major{$1}   = $3;
                $status{$1}  = $4;
        }
}
close (FILE);
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The structure now looks like this (using Data::Dumper):

$students = [
             [
              '45623456',
              'COMP8769',
              'A',
              'Dr.Smith',
              'MWF',
              '10:00',
             ],
             [
              blah, blah, blah..
             ]
           ];
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THe output for all of this is clear by looking at the for loop . I was able to sort by class but is still need to sort to look somthing like => sort by each attribute in student-info-row->Major->sort by student->info.

I was wondering if i could do something like HoH->HOH->HoA. Does anyone have suggestions. From the begining i wanted to do this without using a DBMS/SQL but now i am this close to giving up on using complex data sturcture to do this. Any help will be most appreciated.

The other thing is that as i have mentioned before, i am familiar with the documentation on HoH, AoH, HoA etc. but i do not know how to put this all together and make it work. That is why i would prefer some sample code please.

Why don't you at least take a stab at it so you can bring something to the table? I don't think anyone here wants to do your work for you.

$ perldoc -f sort
[download]

Amel - f.k.a. - kel

Let me see if i can put something together as a starter..