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$pdo = new PDO("mysql:host=localhost;dbname=canaljog_website", "canaljog_sa", "tcmm@0105");

<?php

                  $SQL_F = mysql_query("SELECT * FROM categoria WHERE nome_categoria='slider'");

                  while($ft = mysql_fetch_array($SQL_F)){
                      $id_ft = $ft['id_categoria'];
                  }

                  $SQL_FN = mysql_query("SELECT * FROM noticias WHERE categoria='$id_ft' ORDER BY id_noticia DESC LIMIT 1");
                  while($ftn = mysql_fetch_array($SQL_FN)){

                ?>


             <div class="item active">
              <a href="pages/noticia.php?id=<?php echo $ftn['id_noticia']; ?>">


         <img src="adm/imagens/imgnoticia/<?php echo $ftn['imagem'];?>"  alt="<?php echo $ftn['titulo']; ?>" />

        </a>

<?php } ?>