Why does replacing a placeholder with a fixed value work in a PHP update query, but binding a parameter does not?

When replacing a placeholder with a fixed value in a PHP update query, the query is directly interpolated with the fixed value before execution. However, when binding a parameter, the parameter is sent separately from the query, which can cause issues with certain SQL syntax or data types. To solve this issue, you can bind the parameter with its data type explicitly defined to ensure proper execution of the query. 

// Issue: Binding a parameter in a PHP update query
$sql = "UPDATE table_name SET column_name = :value WHERE id = :id";
$stmt = $pdo->prepare($sql);
$stmt->bindParam(':value', $value);
$stmt->bindParam(':id', $id);
$stmt->execute(); // This may not work as expected

// Fix: Explicitly define the data type when binding the parameter
$sql = "UPDATE table_name SET column_name = :value WHERE id = :id";
$stmt = $pdo->prepare($sql);
$stmt->bindValue(':value', $value, PDO::PARAM_STR);
$stmt->bindValue(':id', $id, PDO::PARAM_INT);
$stmt->execute(); // This will work correctly

Keywords

PHP update query placeholder binding parameter fixed value

Related Questions