在 PHP PDO 中获取最后执行的查询

Posted 2023-02-24

【中文标题】在 PHP PDO 中获取最后执行的查询

【英文标题】：Get Last Executed Query in PHP PDO

【发布时间】：2011-12-04 17:33:31

【问题描述】：

我想知道使用 php PDO 执行什么查询。我有：

<?php

try   
  $DBH = new PDO("mysql:host=localhost;dbname=mytable", 'myuser', 'mypass');  
  
catch(PDOException $e)   
    echo $e->getMessage();  
  

$DBH->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING );  
$DBH->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );  

$STH = $DBH->("INSERT INTO mytable (column1, column2, column3 /* etc...*/) value (:column1, :column2, :column3 /* etc...*/)"); 
$STH->bindParam(':column1', $column1);  
$STH->bindParam(':column2', $column2);  
$STH->bindParam(':column3', $column3);  
 /* etc...*/

$STH->execute();  

// what is my query?

我想得到类似的东西：

INSERT INTO mytable (column1, column2, column3) value ('my first column', 32, 'some text')

有可能吗？谢谢

【问题讨论】：

看看这个***.com/questions/2411182/…

【参考方案1】：

<?php

class MyPDOStatement extends PDOStatement

  protected $_debugValues = null;

  protected function __construct()
  
    // need this empty construct()!
  

  public function execute($values=array())
  
    $this->_debugValues = $values;
    try 
      $t = parent::execute($values);
      // maybe do some logging here?
     catch (PDOException $e) 
      // maybe do some logging here?
      throw $e;
    

    return $t;
  

  public function _debugQuery($replaced=true)
  
    $q = $this->queryString;

    if (!$replaced) 
      return $q;
    

    return preg_replace_callback('/:([0-9a-z_]+)/i', array($this, '_debugReplace'), $q);
  

  protected function _debugReplace($m)
  
    $v = $this->_debugValues[$m[1]];
    if ($v === null) 
      return "NULL";
    
    if (!is_numeric($v)) 
      $v = str_replace("'", "''", $v);
    

    return "'". $v ."'";
  


// have a look at http://www.php.net/manual/en/pdo.constants.php
$options = array(
  PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
  PDO::ATTR_STATEMENT_CLASS => array('MyPDOStatement', array()),
);

// create PDO with custom PDOStatement class
$pdo = new PDO($dsn, $username, $password, $options);

// prepare a query
$query = $pdo->prepare("INSERT INTO mytable (column1, column2, column3)
  VALUES (:col1, :col2, :col3)");

// execute the prepared statement
$query->execute(array(
  'col1' => "hello world",
  'col2' => 47.11,
  'col3' => null,
));

// output the query and the query with values inserted
var_dump( $query->queryString, $query->_debugQuery() );

【讨论】：

preg_replace_callback 是做什么的？

preg_replace_callback() 解析 :placeholder 的查询并将它们传递给回调函数 _debugReplace()，然后返回绑定到 :placeholder 的值。

它不适用于bindParam() 或bindXXX()。

【参考方案2】：

大多数人在 PDO 对象周围创建一个包装类，以便在查询发送到数据库时对其进行记录。几乎没有人使用直接 PDO 对象，因为您可以通过 wrapping, or extending PDO 添加额外的辅助方法。

/**
 * Run a SQL query and return the statement object
 *
 * @param string $sql query to run
 * @param array $params the prepared query params
 * @return PDOStatement
 */
public function query($sql, array $params = NULL)

    $statement = $this->pdo->prepare($sql);

    $statement->execute($params);

    // Save query results by database type
    self::$queries[] = $sql;

    return $statement;