Array interface

[Mladen Gogala <mladen.gogala@xxxxxxxxxxx>]

I wrote a little Perl script, intended to test the difference that array 
insert makes with PostgreSQL. Imagine my surprise when a single  record 
insert into a local database was faster than batches of 100 records. 
Here are the two respective routines:

sub do_ssql
{
   my $exec_cnt = 0;
   while (<FL>)
   {
       chomp;
       my @row = split /$sep/;
       $sth->execute(@row);
       $exec_cnt++;
   }
   $dbh->commit();
   print "Insert executed $exec_cnt times.\n";
}

sub do_msql
{
   my $bsz = shift;
   die("Batch size must be >0!\n") unless $bsz > 0;
   my $exec_cnt = 0;
   my @tstat;
   my (@col1, @col2, @col3);
   while (<FL>)
   {
       chomp;
       my @row = split /$sep/;
       push @col1, $row[0];
       push @col2, $row[1];
       push @col3, $row[2];
       if ($. % $bsz == 0)
       {
           my $tuples = $sth->execute_array({ArrayTupleStatus => \@tstat},
                                            \@col1, \@col2, \@col3);
           die("Multiple insert failed!\n") if (!$tuples);
           @col1 = ();
           @col2 = ();
           @col3 = ();
           $exec_cnt++;
       }

   }
   if ($#col1 >= 0)
   {
       my $tuples = $sth->execute_array({ArrayTupleStatus => \@tstat},
                                        \@col1, \@col2, \@col3);
       die("Multiple insert failed!\n") if (!$tuples);
       $exec_cnt++;
   }
   $dbh->commit();
   print "Insert executed $exec_cnt times.\n";
}


The variable "$sth" is a prepared  statement handle for the insert statement.

--

Mladen Gogala 
Sr. Oracle DBA
1500 Broadway
New York, NY 10036
(212) 329-5251
http://www.vmsinfo.com 
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