Yep, Ovid is dead on here -- the information for which you are looking is stored in the Oracle data dictionary.

I hope the following example helps. (Note: There are more fields in dba_tab_columns... you might want to look around for other goodies.) Make sure to set the ORAUSER, ORAPASS, and ORATNS constants to values appropriate to your system. (Oh, and you may not have a SCOTT.EMP table. *Smiles*)

#!/usr/bin/perl -w
use strict;

#-- Use modules
use DBD::Oracle;
use DBI;

#-- Define local constants
use constant TRUE      => 1;
use constant FALSE     => 0;

use constant ORAUSER   => 'my_ora_user';
use constant ORAPASS   => 'secret_password';
use constant ORATNS    => 'ora_db_tns_name';

#-- Define local variables
my $gDBHandle;
my $gSQLCmd;
my $gSQLHandle;
my $gTabName;
my $gTabSchema;
my @gFields;

#-- Initialize local variables
$gSQLCmd = 'SELECT column_name,      ' .
           '       nullable,         ' .
           '       data_type,        ' .
           '       data_length       ' .
           '   FROM dba_tab_columns  ' .
           '   WHERE owner = ?       ' .
           '     AND table_name = ?  ' .
           '   ORDER BY column_id    ';

$gTabName = 'EMP';
$gTabSchema = 'SCOTT';

#-- Connect to the database
$gDBHandle = DBI->connect
  (
    'dbi:Oracle:' . ORATNS, ORAUSER, ORAPASS,
    {
      AutoCommit  => FALSE,
      PrintError  => FALSE,
      RaiseError  => FALSE,
    }
  ) || die 'Could not connect to Oracle ['.$DBI::errstr.' - '.$DBI::er
+r.']';

#-- Get the data
$gSQLHandle = $gDBHandle->prepare($gSQLCmd) 
  || die 'Error with SQL statement ['.$DBI::errstr.' - '.$DBI::err.']'
+;

$gSQLHandle->execute($gTabSchema, $gTabName) 
  || die 'Error with SQL statement ['.$DBI::errstr.' - '.$DBI::err.']'
+;

while (@gFields = $gSQLHandle->fetchrow_array)
{
  print $gFields[0],"\t",$gFields[1],"\t",$gFields[2],"\t",$gFields[3]
+,"\n";
}

#-- Close the database connection
$gDBHandle->disconnect();

#-- Exit
exit;

#-- End of Example
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