如何使用 PDO 使数据库查询的准备工作更高效？

Question

例如，我的数据库中有几个表，例如用户、产品等。对于每个表，我至少有一个关联的类和几个方法，例如 addUser、updateUserName、updateUserPassword 等. 对于每种方法，我在使用 PDO 时都需要准备 SQL，如下所示：

$sql = "INSERT INTO `user`
(`id`,`username`,`password`,`log`)
VALUES
(:id, :username, :password, :log)";

然后我将值存储在这样的数组中：

$array = array('id'=>$id, 'username'=>$username, 'password'=>$password, 'log'=>$log);

然后我使用 PDO 的东西：

$pdo = new PDO($dsn, $user, $password);
$mysql = $pdo->prepare($sql);
$mysql->execute($array);

所以看来，对于 User 类中的所有不同方法，我需要做这个“准备”的事情。是不是太乏味了？有没有更有效的方法来做到这一点，尤其是考虑到存在一个包含许多列的表时我将值存储在数组中的部分，在这种情况下我会得到一个很长的准备语句？

Answer 1

既然你自己是插入和更新试试这些

        //to query the database with prepared statements
    public function query ($sql, $parameters = array()) {

        //setting error to false to prevent interferance from previous failed queries
        $this->_error = false;

        //prepare SQL statement
        if ($this->_query = $this->_pdo->prepare ($sql)) {

            //checking to see whether any parameters were submitted along
            if (count($parameters)) {

                //setting the initial position for the binding values
                $position = 1;

                //getting the individual parameters and binding them with their respective fields
                foreach ($parameters as $param) {
                    $this->_query->bindValue ($position, $param);
                    $position++;
                }
            }
        }

        //executing the sql
        if ($this->_query->execute()) {
            //getting the number of rows returned
            $this->_count = $this->_query->rowCount();

            //keeping the results returned
            $this->_results = $this->_query->fetchAll (PDO::FETCH_OBJ);
        } else {
            $this->_error = true;
        }
        //returning all values of $this
        return $this;
    }


        //to insert data into a prescribed table
    public function insert ($table, $parameters = array()) {

        //checking if the $fields are not empty
        if (count($parameters)) {

            //making the keys of the array fields
            $fields = array_keys ($parameters);

            //creating the to-bind-values in the form (?, ?, ...)
            $values = '';
            $x = 1;

            foreach ($parameters as $field => $value) {

                //$value is different from $values
                $values .= '?';

                if ($x < count($parameters)) {
                    $values .= ', ';
                    $x++;
                }
            }
            //generating $sql
            $sql = "INSERT INTO `{$table}` (`".implode ('`, `', $fields)."`) VALUES ({$values})";

            //executing the sql
            if (!$this->query($sql, $parameters)->error()) {
                return true;
            }
        }
        return false;
    }

    //to update data in a prescribed table
    public function update ($table, $id = null, $parameters = array()) {

        //checking that $parameters is not an empty array
        if (count($parameters)) {
            $set = '';
            $x = 1;

            foreach ($parameters as $field => $value) {
                $set .= "`{$field}` = ?";

                if ($x < count($parameters)) {
                    $set .= ', ';
                    $x++;
                }
            }

            if ($id) {
                //generating query
                $sql = "UPDATE `{$table}` SET {$set} WHERE `id` = {$id}";
            } else {
                $sql = "UPDATE `{$table}` SET {$set} WHERE 1";
            }

            //executing the query
            if (!$this->query($sql, $parameters)->error()) {
                return true;
            }
        }
        return false;
    }