NYCPHP Meetup

[Kevin Castiglia]

Hello all,

I am trying to decide whether to use MDB2 or PHP PDO. I am sort of leaning
towards using PHP PDO at the moment, but I'd rather ask some experts on
their opinion. Just fyi, I am using PHP 5.2.6-1+lenny3 and mySQL on a Linux
server, I have created a table of about 20 fields and loaded 20,000 rows of
data into the table. I then ran a select with a where clause and an update
on every row, while testing performance of MDB2 and PHP PDO. I also tested
whether a raw statement query to the server would be faster than forming a
prepare statement and then executing using both MDB2 and PHP PDO.

In my tests I found that using raw statements in MDB2 and PHP PDO is faster
than using a prepare statement and then executing it for each row (raw
statement was much faster using MDB2 and only slightly faster using PHP
PDO). To capture the times I issued a microtime() just before the
query/execute and just after.

For processing 20,000 transactions:

Here are my results for the MDB2 raw Select php program:

-  ran for 10.1 seconds vs 17.7 seconds for the prepare. The MDB2 raw update
ran for 12.3 seconds vs 20.3 seconds for the MDB2 prepare.

Here are my results for the PDO raw Select PHP program:

- ran for 8.3 seconds vs 8.3 seconds for the prepare. The PDO raw update ran
for 5.78 seconds vs 5.92 seconds for the PDO prepare.

I have pasted two of my programs' source code: the first uses prepares and
MDB2 and the second uses prepares and PHP PDO.

****I was told that using a prepare is much faster then using raw sql but my
test results prove otherwise. Why is the prepare and execute method is
slower than building the statement manually and querying the server?
Shouldn't the prepare and execute method be faster since you only need to
generate the prepare once as opposed to generating the statements within a
loop?
-Kevin


<?php
$fpiDataAddr = fopen('outputAddr.txt','r') or die("can not open New In File
");
ini_set('memory_limit', -1);
require_once('MDB2.php');
//Connect to the Database
$arrDsn = array(
    'phptype'  => 'mysql',
    'username' => 'u1',
    'password' => 'p1',
    'hostspec' => 'localhost',
    'database' => 'demo',
);
$mdb2 =& MDB2::connect($arrDsn);

$seqno = 0;


        //for normal prepare
        $sql1 = 'SELECT * FROM demo.kb_addr WHERE UNIQUE_NUM = ?';

        $time_start = getmicrotime();
        $sth1 = $mdb2->prepare($sql1, MDB2_PREPARE_RESULT);

        $sql2 = 'UPDATE demo.kb_addr SET AM_CITY = ? WHERE UNIQUE_NUM = ?';
        $arrType = array('text','integer');
        $sth2 = $mdb2->prepare($sql2, $arrType, MDB2_PREPARE_MANIP);


while($inrec = fgetcsv($fpiDataAddr,0,',','"')){

        if($seqno == 0){
        $x= count($inrec);
        $arrFields = array();
        for ($y = 0; $y < $x; $y++) {
            $arrFields[$inrec[$y]] = $y; //creates associative array that
associates fields with the index in $inrec
        }

        echo "Array of Field Names From Header Record in Input data is \n";
        print_r($arrFields);
        $seqno++;
        continue;    }


        $key = 0+$inrec[$arrFields['Unique #']];
        //for normal prepare
        $values = array($key);

        $time_start1 = getmicrotime();
        $affectedRows =& $sth1->execute($values);
        $arrCnt['select'] += getmicrotime() - $time_start1;

        $time_elapsed = getmicrotime() - $time_start;

        if (PEAR::isError($res)) {
            die($res->getMessage());
        }

        $values = array();
        $values = array('Kevin',$key);

        $time_start1 = getmicrotime();
        $affectedRows =& $sth2->execute($values);
        $arrCnt['update'] += getmicrotime() - $time_start1;
        $time_elapsed = getmicrotime() - $time_start;

        if (PEAR::isError($res)) {
            die($res->getMessage());
        }

        if($seqno > 20000) break;
        $seqno++;
}

echo "total: ". $time_elapsed."\n";
echo "execution times:\n";
var_dump($arrCnt);
$rate = $time_elapsed / $seqno;
echo "rate: ".$rate."\n";

    // ***************
    // Calculate the time including fractions of a second
    // ***************
    function getmicrotime() {
        $mtime = microtime();
        $mtime = explode(' ', $mtime);
        return($mtime[1] + $mtime[0]);
    }

fclose($fpiDataAddr) or die("can not close data file");

$mdb2->disconnect();

?>

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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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<?php
$fpiDataAddr = fopen('outputAddr.txt','r') or die("can not open New In File
");
ini_set('memory_limit', -1);

//Connect to the Database
$dsn = 'mysql:host=localhost;dbname=demo';

$connHandle = new PDO ($dsn,'u1','');

$seqno = 0;
$time_start = getmicrotime();

        //for normal prepare
        $sql1 = 'SELECT * FROM demo.kb_addr WHERE UNIQUE_NUM = ?';

        $sth1 = $connHandle->prepare($sql1);

        $sql2 = 'UPDATE demo.kb_addr SET AM_CITY = ? WHERE UNIQUE_NUM = ?';
        $sth2 = $connHandle->prepare($sql2);

while($inrec = fgetcsv($fpiDataAddr,0,',','"')){

        if($seqno == 0){
        $x= count($inrec);
        $arrFields = array();
        for ($y = 0; $y < $x; $y++) {
            $arrFields[$inrec[$y]] = $y; //creates associative array that
associates fields with the index in $inrec
        }

        $seqno++;
        continue;    }


        $key = 0+$inrec[$arrFields['Unique #']];
        //for normal prepare
        $values = array($key);

        $time_start1 = getmicrotime();
        $affectedRows =& $sth1->execute($values);
        $arrCnt['select'] += getmicrotime() - $time_start1;

        $time_elapsed = getmicrotime() - $time_start;

        if (PEAR::isError($res)) {
            die($res->getMessage());
        }

        $values = array();
        $values = array('Kevin',$key);

        $time_start1 = getmicrotime();
        $affectedRows =& $sth2->execute($values);
        $arrCnt['update'] += getmicrotime() - $time_start1;
        $time_elapsed = getmicrotime() - $time_start;

        if (PEAR::isError($res)) {
            die($res->getMessage());
        }



        if($seqno > 20000) break;
        $seqno++;
}

echo "total: ". $time_elapsed."\n";
echo "execution times:\n";
var_dump($arrCnt);
$rate = $time_elapsed / $seqno;
echo "rate: ".$rate."\n";

    // ***************
    // Calculate the time including fractions of a second
    // ***************
    function getmicrotime() {
        $mtime = microtime();
        $mtime = explode(' ', $mtime);
        return($mtime[1] + $mtime[0]);
    }

fclose($fpiDataAddr) or die("can not close data file");

//disconnect
$connHandle = null;

?>
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