I have this DBI script that queries a MySQL database. I prepare all my queries before I execute them. It takes about 30 min to run this script using DBD::mysql and 20+ hours for DBD::CSV. With DBD::MySQL it seems to crunch about 5000 rows at once then rests for 5 minutes. I'm not sure what it's doing.

I read in the book "Programming the Perl DBI" that I can use the attribute "mysql_store_result" and store it in memory. Any other ideas to speed up this query?

The tables are the following sizes:
sec = 21,000 rows @ 2.3 MB
bt = 1274 rows @ 675 KB
stats = 426 rows @ 95 KB
my $database = "db";
my $db_server = "localhost";
my $user = "user";
my $password = "pass";

my $dbh = DBI->connect("DBI:mysql:$database:$db_server",$user,$passwor
+d);

my $sth_sec = $dbh->prepare("SELECT KEY, TEST, INSTANCE, ID, HID FROM 
+sec")
        or die "Can't prepare SQL statement: $DBI::errstr\n";

my $sth_bt = $dbh->prepare("SELECT NAME, STATE FROM bt WHERE ID =? AND
+ HID=?")
        or die "Can't prepare SQL statement: $DBI::errstr\n";

my $sth_stats = $dbh->prepare("SELECT CCS, kbps, MBytes FROM stats WHE
+RE ID=? AND HID=? & INSTANCE=?")
        or die "Can't prepare SQL statement: $DBI::errstr\n";

$sth_sec->execute()
        or die "Can't execute SQL statement: $DBI::errstr\n";

open(TRAFFICSTATS,'>',"NoThroughput.csv") || die("Cannot Open File");
{
   my $old_sel = select(TRAFFICSTATS);
   $| = 1;  # Auto-flush.
   select($old_sel);
}

print TRAFFICSTATS "KEY,ID,HID,NAME,STATE,CCS,kbps,MBytes\n";

while ( my @row = $sth_sec->fetchrow_array ) {

  my ( $keyId,
       $testCarrier,
       $instanceId,
       $id,
       $hId ) = @row;

   $sth_bt->execute( $id, $hId );

   @row = $sth_bt->fetchrow_array;

   my ( $name, $state ) = @row;

   $sth_stats->execute($id, $hId, $instanceId );

   @row = $sth_stats->fetchrow_array;

   my ( $CCS, $kbps, $mBytes ) = @row;

   print TRAFFICSTATS "$keyId,$id,$hId,$name,$state,$CCS,$kbps,$mBytes
+\n";
}

close TRAFFICSTATS;

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In reply to Speed up DBD::MySQL Queries by awohld

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