PDO和原始mysql的性能对比

mysql表：2M，5W行：

Mysql连接：

<?php

  $link = mysql_connect('localhost', 'lcms2', 'abcd');
  mysql_select_db("lcms2");
  mysql_query("SET NAMES 'utf8'");

  $time = microtime(1);

  for ($i=1; $i<10000;$i  ) {
       $sql = "SELECT * from `cl_translation` WHERE `varName`='my group'";

       $result = mysql_query($sql,$link);
       if (!$result) {
                  echo "Could not successfully run query ($sql) from DB: " . mysql_error();
                          exit;
           }

       $rows = array();

      while ($row = mysql_fetch_assoc($result)) {
          $rows[] = $row;

          }

    }

  $intval_time = microtime(1) - $time;
  echo $intval_time . "";

  var_dump($rows);


  ?>

PDO连接代码：

<?php

  $dsn = "mysql:dbname=lcms2;host=localhost";
  $user = "lcms2";
  $password = "abcd";

  try{
          #$dbh = new pdo($dsn, $user, $password,array(PDO::ATTR_PERSISTENT => true));
          $dbh = new pdo($dsn, $user, $password);
  } catch (PDOException $e){
          echo "Connetion failed: " . $e->getMessage();
  }
  $dbh->exec("SET NAMEs 'utf8'");
  $ph = array();

  $time = microtime(1);

          $sql = "SELECT * from `cl_translation` WHERE `varName`=:string";

          $ph[0] = $dbh->prepare($sql);
  for ( $i=1; $i<10000; $i  ) {

          $ph[0]->execute(array('string'=>'my group'));

  }
  $result = $ph[0]->fetchAll();

  $intval_time = microtime(1) - $time;
  echo $intval_time . "";

  var_dump($result);


  ?>

pdo直接查询，不用prepare语句：

<?php
  $time = microtime(1);


  $dsn = "mysql:dbname=lcms2;host=localhost";
  $user = "lcms2";
  $password = "lsrzlcms";

  try{
          #$dbh = new pdo($dsn, $user, $password,array(PDO::ATTR_PERSISTENT => true));
          $dbh = new pdo($dsn, $user, $password);
  } catch (PDOException $e){
          echo "Connetion failed: " . $e->getMessage();
  }
  $dbh->exec("SET NAMEs 'utf8'");
  $ph = array();

  for ( $i=1; $i<10000; $i  ) {

          $sql = "SELECT * from `cl_translation` WHERE `varName`='my group'";

          $ph = $dbh->query($sql);
          if ( !$ph ) {
                  var_dump($dbh->errorInfo());
                  die("Error when execute query" );
          }
  }

  $result = $ph->fetchAll();

  $dbh=NULL;

  $intval_time = microtime(1) - $time;
  echo $intval_time . "";

  var_dump($result);


  ?>

连接结果：

第一次： 0.014165878295898s
0.00062799453735352
0.00014495849609375

改变id值
0.00049090385437012

0.00012493133544922


改变prepare的值：

0.051913022994995

0.00035595893859863
0.00033116340637207


mysql驱动：
0.00032401084899902
0.00030779838562012



mysql 1000次
0.30312514305115
0.30235195159912

mysql 10000次：
3.0247800350189
3.043329000473
3.0260350704193

pdo 10000次，包括prepare内的循环：
0.89934897422791
0.89384698867798

pdo 10000次，不包括prepare内的循环，只循环excute：
0.79944610595703
0.79354596138

pdo　不用statements语句，直接查询：
0.877690076828
0.81276917457581
0.82689189910889

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害死人了，for后忘了加大括号，导致第一次进行mysql_select时，没有执行数据库查询！！！

pdo的效率还是很高的，终于松了一口气！

另外：PDO::MYSQL_ATTR_USE_BUFFERED_QUERY好像没有作用。

保持连接对pdo查询影响不大，只影响连接。