What is the difference between bindParam and bindValue in PHP when working with PDO?

bindParam and bindValue are both used to bind values to placeholders in SQL queries when working with PDO in PHP. The main difference between the two is that bindParam binds the parameter by reference, meaning that if the value of the variable changes after binding, the bound parameter value will also change. On the other hand, bindValue binds the parameter by value, meaning that the bound parameter value is set at the time of binding and changes to the original variable will not affect the bound parameter value.

// Using bindParam
$stmt = $pdo->prepare("SELECT * FROM table WHERE column = :value");
$value = 'example';
$stmt->bindParam(':value', $value, PDO::PARAM_STR);
$value = 'new_example'; // This change will affect the bound parameter value

// Using bindValue
$stmt = $pdo->prepare("SELECT * FROM table WHERE column = :value");
$value = 'example';
$stmt->bindValue(':value', $value, PDO::PARAM_STR);
$value = 'new_example'; // This change will not affect the bound parameter value