原文：http://www.mysqltutorial.org/php-mysql-blob/

     pdo = new PDO($conStr, self::DB_USER, self::DB_PASSWORD);            //for prior PHP 5.3.6            //$conn->exec("set names utf8");        } catch (PDOException $e) {            echo $e->getMessage();        }    }    /**     * insert blob into the files table     * @param string $filePath     * @param string $mime mimetype     * @return bool     */    public function insertBlob($filePath, $mime) {        $blob = fopen($filePath, 'rb');        $sql = "INSERT INTO files(mime,data) VALUES(:mime,:data)";        $stmt = $this->pdo->prepare($sql);        $stmt->bindParam(':mime', $mime);        $stmt->bindParam(':data', $blob, PDO::PARAM_LOB);        return $stmt->execute();    }    /**     * update the files table with the new blob from the file specified     * by the filepath     * @param int $id     * @param string $filePath     * @param string $mime     * @return bool     */    function updateBlob($id, $filePath, $mime) {        $blob = fopen($filePath, 'rb');        $sql = "UPDATE files                SET mime = :mime,                    data = :data                WHERE id = :id;";        $stmt = $this->pdo->prepare($sql);        $stmt->bindParam(':mime', $mime);        $stmt->bindParam(':data', $blob, PDO::PARAM_LOB);        $stmt->bindParam(':id', $id);        return $stmt->execute();    }    /**     * select data from the the files     * @param int $id     * @return array contains mime type and BLOB data     */    public function selectBlob($id) {        $sql = "SELECT mime,                        data                   FROM files                  WHERE id = :id;";        $stmt = $this->pdo->prepare($sql);        $stmt->execute(array(":id" => $id));        $stmt->bindColumn(1, $mime);        $stmt->bindColumn(2, $data, PDO::PARAM_LOB);        $stmt->fetch(PDO::FETCH_BOUND);        return array("mime" => $mime,            "data" => $data);    }    /**     * close the database connection     */    public function __destruct() {        // close the database connection        $this->pdo = null;    }}$blobObj = new BobDemo();// test insert gif image$blobObj->insertBlob('images/php-mysql-blob.gif',"image/gif");$a = $blobObj->selectBlob(1);header("Content-Type:" . $a['mime']);echo $a['data'];// test insert pdf//$blobObj->insertBlob('pdf/php-mysql-blob.pdf',"application/pdf");//$a = $blobObj->selectBlob(2);// save it to the pdf file//file_put_contents("pdf/output.pdf", $a['data']);// $a = $blobObj->selectBlob(2);// header("Content-Type:" . $a['mime']);// echo $a['data'];// replace the PDF by gif file// $blobObj->updateBlob(2, 'images/php-mysql-blob.gif', "image/gif");// $a = $blobObj->selectBlob(2);// header("Content-Type:" . $a['mime']);// echo $a['data'];