ZF2改變我的表達式並返回錯誤（Postgre，Distinct）

Question

我必須做一個SELECT，我將通過列idcontrato來區分行。我做得很好用SQL ...

SELECT DISTINCT ON (idcontrato) * 
FROM cad_emprestimo 
WHERE numerobeneficio = '1135346515'; 

但是，當我試圖做同樣的ZF2：

$emprestimos = (new EmprestimoTable())->select(function(Select $select) use($cliente) { 
     $select->columns([new Expression('DISTINCT ON (idcontrato) *')]); 
     $select->where->equalTo('numerobeneficio', $cliente->getBeneficio()->getNumero()); 
}); 

我得到了以下錯誤：

SQLSTATE[42601]: Syntax error: 7 ERRO: erro de sintaxe em ou próximo a "AS" 
LINE 1: SELECT DISTINCT ON (idcontrato) * AS Expression1 FROM "cad_e... 
             ^

這' AS Expression1'由ZF2添加...我不知道如何刪除它。

Answer 1

顯而易見的解決方案，我發現是運行原始SQL：

$dbAdapter  = GlobalAdapterFeature::getStaticAdapter(); 
    $numBeneficio = $cliente->getBeneficio()->getNumero(); 
    $sqlEmprestimos = "SELECT DISTINCT ON (idcontrato) * FROM cad_emprestimo WHERE numerobeneficio = '".$numBeneficio."'; "; 
    $dataSource  = $dbAdapter->createStatement($sqlEmprestimos)->execute(); 
    $emprestimos = (new \Zend\Db\ResultSet\ResultSet())->initialize($dataSource); 

無論如何，我不是很滿意這個，這個代碼是醜陋的地獄。

Answer 2

試試下面的代碼

$emprestimos = (new EmprestimoTable())->select(function(Select $select) use($cliente) { 
     $select->columns([new Expression('DISTINCT(idcontrato) AS idcontrato'), '*']); 
     $select->where->equalTo('numerobeneficio', $cliente->getBeneficio()->getNumero()); 
});