chamilo / chamilo-lms

     * @param int $id              The id (an integer number) of the corresponding database record.

     * @return string|bool              Returns the requested data as an array or FALSE on failure.

     */

    public static function get_course_request_info($id)

    {

        $id = (int)$id;

        $sql = "SELECT *

                FROM ".Database :: get_main_table(TABLE_MAIN_COURSE_REQUEST)."

                WHERE id = ".$id;

        $result = Database::query($sql);

        if (Database::num_rows($result) > 0) {

            return Database::fetch_array($result);

        }

        return false;

    }

    /**

     * Gets the code of a given course request using its database id as an access key.

	 * Check availability of a survey code

	 * @param string $survey_code

	 */

    public function is_survey_code_available($survey_code)

    {

		$table_sur = Database :: get_course_table(TABLE_SURVEY);

		$sql = "SELECT * FROM $table_sur

		        WHERE

		            c_id = ".$this->destination_course_id." AND

		            code = '".self::DBUTF8escapestring($survey_code)."'";

		$result = Database::query($sql);

        if (Database::num_rows($result) > 0) {

            return false;

        } else {

            return true;

        }

	}

	/**

	 * Restore survey-questions

     * @assert ('') === false

     * @assert ('xyzxyzxyz') === true

     */

    public static function is_username_available($username)

    {

        if (empty($username)) {

            return false;

        }

        $table_user = Database :: get_main_table(TABLE_MAIN_USER);

        $sql = "SELECT username FROM $table_user

                WHERE username = '".Database::escape_string($username)."'";

        $res = Database::query($sql);

        return Database::num_rows($res) == 0;

    }

    /**