Como remover o erro Warning: Invalid argument supplied for foreach() i

Como poderia remover o erro Warning: Invalid argument supplied for foreach() in /var/www/PlanejamentoEstrategico/view/pgs/indoperacionais/relIndOperacionais.php on line 241 que é esse ai

foreach($_indoperacionais as $_indoperacional)

todo o código

<?php

 /* codigo para gerar os paramentros */
$ano = $_POST["ano"];
$_perspectiva = $_POST["perspectiva"];

if ($_POST["semestre"] == "primeiro") {

$_parametros = array ( "ano" => $ano,

"mes1" => 1, "mes2" => 2, "mes3" => 3,
"mes4" => 4, "mes5" => 5, "mes6" => 6,

"nomeMes1" => "Janeiro", "nomeMes2" => "Fervereiro", "nomeMes3" => "Março", "nomeMes4" => "Abril", "nomeMes5" => "Maio", "nomeMes6" => "Junho",

"perspectiva" => $_perspectiva);
}else if ($_POST["semestre"] == "segundo") {

$_parametros = array ( "ano" => $ano,

"mes1" => 7, "mes2" => 8, "mes3" => 9,
"mes4" => 10, "mes5" => 11, "mes6" => 12,

"nomeMes1" => "Julho", "nomeMes2" => "Agosto", "nomeMes3" => "Setembro", "nomeMes4" => "Outubro", "nomeMes5" => "Novembro", "nomeMes6" => "Dezembro", "perspectiva" => $_perspectiva); }else {

$error = "ERRO";
}

//echo "<pre>"; print_r ($_POST);exit;

//Instanciando a classe

$_model = new model_Indoperacionais();

$_indoperacionais = $_model->RetornaIndoperacionais($ano,$_parametros,$_perspectiva);
$_indoperacionais = $_model->RetornaPerspectivas($_perspectiva);
 echo '<h3 align=center>'.$_POST["perspectiva"].'</h3>';
 echo '<h1 align=center>'.($ano).'</h1>';
 echo '<h6 align=center>'.$_POST["semestre"].'</h6>';

 //echo "</pre>"; print_r($_indoperacional); exit;
 foreach($_indoperacionais as $_indoperacional){
 echo '<tr>';
 echo '<td align=center>'.$_indoperacional['nome_tema'].'</td>';
 echo '<td align=center>'.$_indoperacional['indicadores'].'</td>';
 echo '<td align=center>'.$_indoperacional['responsavel'].'</td>';
 echo '<td align=center>'.$_indoperacional['metas'].'</td>';
 echo '<td align=center>'.$_indoperacional['01'].'</td>';
 echo '<td align=center>'.$_indoperacional['02'].'</td>';
 echo '<td align=center>'.$_indoperacional['03'].'</td>';
 echo '<td align=center>'.$_indoperacional['04'].'</td>';
 echo '<td align=center>'.$_indoperacional['05'].'</td>';
 echo '<td align=center>'.$_indoperacional['06'].'</td>';
 echo '</tr>';

//print_r($_parametros);
}

?>

class model_Indoperacionais extends MysqlConnection{

private $indoperacionais;

public function RetornaIndoperacionais($ano,$_parametros,$_perspectiva){

 if($ano == "2016"){
 $_base = "pla_est_2016";
 }else{
 $_base = "pla_est";
 }

 $Query = ("SELECT i.codiniciativa,
 te.nome as nome_tema,
 te.codtemaestrategico as cod_te,
 p.observacoes as per_obs,
 te.sequencia as tem_sequencia,
 p.sigla as per_sigla,
 p.nome as nome_perspectiva,
 p.codperspectiva as cod_perspectiva,
 o.sequencia as sequencia_obj,
 o.codobjetivo as cod_obj,
 o.nome as nome_obj,concat(p.sigla, ' ', te.sequencia,
 '.', o.sequencia, '.',i.sequencia) as codigo,i.nome as nom_iniciativa,
 i.sequencia as iniciativa_sequencia,
 i.metas,i.responsavel,i.indicadores,
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) = $ano AND month(a.data) = ".$_parametros['mes1']." ORDER BY a.data DESC LIMIT 1),
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) <= $ano AND month(a.data) < ".$_parametros['mes1']." AND curdate() >= '$ano-".$_parametros['mes1']."-01' ORDER BY a.data DESC LIMIT 1), 0)) as '01',
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) = $ano AND month(a.data) = ".$_parametros['mes2']." ORDER BY a.data DESC LIMIT 1),
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) <= $ano AND month(a.data) < ".$_parametros['mes2']." AND curdate() >= '$ano-".$_parametros['mes2']."-01' ORDER BY a.data DESC LIMIT 1), 0)) as '02',
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) = $ano AND month(a.data) = ".$_parametros['mes3']." ORDER BY a.data DESC LIMIT 1),
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) <= $ano AND month(a.data) < ".$_parametros['mes3']." AND curdate() >= '$ano-".$_parametros['mes3']."-01' ORDER BY a.data DESC LIMIT 1), 0)) as '03',
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) = $ano AND month(a.data) = ".$_parametros['mes4']." ORDER BY a.data DESC LIMIT 1),
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) <= $ano AND month(a.data) < ".$_parametros['mes4']." AND curdate() >= '$ano-".$_parametros['mes4']."-01' ORDER BY a.data DESC LIMIT 1), 0)) as '04',
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) = $ano AND month(a.data) = ".$_parametros['mes5']." ORDER BY a.data DESC LIMIT 1),
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) <= $ano AND month(a.data) < ".$_parametros['mes5']." AND curdate() >= '$ano-".$_parametros['mes5']."-01' ORDER BY a.data DESC LIMIT 1), 0)) as '05',
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) = $ano AND month(a.data) = ".$_parametros['mes6']." ORDER BY a.data DESC LIMIT 1),
 ifnull((SELECT a.percentual FROM $_base.avaliacoes a WHERE a.status = 'A' AND a.codiniciativa = i.codiniciativa AND year(a.data) <= $ano AND month(a.data) <".$_parametros['mes6']." AND curdate() >= '$ano-".$_parametros['mes6']."-01' ORDER BY a.data DESC LIMIT 1), 0)) as '06'

FROM $_base.perspectivas p LEFT JOIN $_base.temasestrategicos te ON p.codperspectiva = te.codperspectiva LEFT JOIN $_base.objetivos o ON te.codtemaestrategico = o.codtemaestrategico LEFT JOIN $_base.iniciativas i ON o.codobjetivo = i.codobjetivo

WHERE p.codperspectiva = '$_perspectiva' AND p.status = 'A' AND te.status = 'A' AND o.status = 'A' AND i.status = 'A'ORDER BY p.sequencia ASC,te.sequencia ASC,
 o.sequencia ASC,CAST(i.sequencia AS DECIMAL) ASC");

 //echo "</pre>"; print_r($_perspectiva); exit;

 try {
 $this->search = $this->MySql->prepare($Query);
 //$this->search->bindParam(":nome", $this->indoperacionais);
 $this->search->execute();

 } catch(PDOException $e) {
 die($e->getMessage());
 }

 $_result = $this->search->fetchAll(PDO::FETCH_ASSOC);
//echo "</pre>"; print_r($_result); exit;
 return $_result;
}
 Public function RetornaPerspectivas($_perspectiva){
$Query = " Select nome FROM perspectivas WHERE codperspectiva = '$_perspectiva'" ;

 try {
 $this->search = $this->MySql->prepare($Query);
 $this->search->execute();

 } catch(PDOException $e) {
 die($e->getMessage());
 }

 $_result = $this->search->fetchAll(PDO::FETCH_ASSOC);
 return $_perspectiva;

}
 }

preciso da ajuda de vocês .