Change.php

<?php
abstract class ZendDbSchema_Db_Migration_Change
{
    protected $_downgradable = true;

    protected $_databasesConfig = array();

    protected $_tablesConfig = array();


    protected $_description = '';

    abstract function up();

    abstract function down();

    public function __toString()
    {
        return $this->getVersion();
    }

    public function getName()
    {
        return get_class($this);
    }

    public function getDescription()
    {
        return $this->_description;
    }

    public function isDowngradable()
    {
        return (bool) $this->_downgradable;
    }

    public function getTablesConfig()
    {
        return $this->_tablesConfig;
    }

    public function getDatabasesConfig()
    {
        return $this->_databasesConfig;
    }

    public function getVersion()
    {
        return substr(get_class($this), 10);
    }

    public function compareVersion($version, $operator = null)
    {
        if ($version instanceof ZendDbSchema_Db_Migration_Change) {
            $version = $version->getVersion();
        }
        $version = strtolower($version);
        $current = strtolower($this->getVersion());

        return version_compare($version, $current, $operator);
    }

    public static function fromFile($file)
    {
        if ($file instanceof SplFileInfo) {
            $file =  $file->getPathname();
        }
        if (!realpath($file) || !is_file($file)) {
            throw new ZendDbSchema_Db_Migration_Exception("{$file} not exists");
        }
        include_once $file;
        $class = ZendDbSchema_Db_Migration_Skeleton::getClassName($file);
        return new $class;
    }
}