abstract sql object

gistfile1.php

<?php 

use Zend\Db\Sql\Sql;
$sql = new Sql($adapter);
$oSelect = $sql->select('table_test');
$oSelect->columns(array('*'))->where(array('test' => 'ok')->limit(1);
$sqlString = $sql->getSqlStringForSqlObject($oSelect);

//see https://github.com/zendframework/zf2/issues/3224

in Model Table class :
$sql = $this->tableGateway->getSql();
$select = $sql->select();
$select->where(array('column_name' => 'some value'));

$sql->getSqlstringForSqlObject($select);