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
[download]

Just drop the TOP 1 from the SQL. I added that to prevent the DB from selecting all records and doing to much work. However, having the $sth->finish call at the end should minimize the overhead by merely finishing up the statement handle without fetching the subsequent rows.

Of course, Oracle should support some form of the TOP syntax, but I don't know Oracle.

Cheers,
Ovid

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Just execute a query with a false where clause:

select * from ... where 1=0
[download]

This will return an empty result set, but you'll still get all the column headers, names, etc.

Michael

OK. I think I see now. Another question: How do you get the types, like varchar2(2000), number(3), date, etc? Basically I want to get all the results from a DESC operation into my Perl script. Thanks!

Robert

While I am not familiar with the TOP syntax, I bet ROWNUM can be used to do the same. ROWNUM is a the number of a row as it was retrieved from the table (this differs from the display order) -- to limit results to 10 rows, you can use WHERE ROWNUM <= 10. (Please note: this takes place before sorting, so it is no good for getting the "top 10" and such.)

SELECT *
  FROM scott.emp
  WHERE ROWNUM = 1;
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