$oc_item_synchro_tbl = $this->getRs()->getTableName('oc_item_synchro');
$oc_other_config = mysql_escape_string($serialized);
$id = 255;
$this->getConnection()->rawQuery("UPDATE $oc_item_synchro_tbl SET oc_other_config = '$oc_other_config' WHERE oc_product_id = '$id'");

public function addProduct($data)
{

    $oc_item_synchro = $this->getRs()->getTableName('oc_item_synchro');
    $id = (int)$data['oc_product_id'];
    $now = strtotime("Y-m-d h:ia");
    $conn = $this->getConnection('core_write');

    $sql = "INSERT INTO $oc_item_synchro SET ";
    $sql .= "oc_product_id = :OC_PRODUCT_ID, ";
    $sql .= "oc_item_category_id = :OC_ITEM_CATEGORY_ID, ";
    $sql .= "oc_item_duration = :OC_ITEM_DURATION, ";
    $sql .= "item_delivery_time = :ITEM_DELIVERY_TIME, ";
    $sql .= "is_posted = :IS_POSTED, ";
    $sql .= "oc_synchro_time = :NOW";
    $binds = array(
        'OC_PRODUCT_ID' => $id,
        'OC_ITEM_CATEGORY_ID' => (int)$data['oc_item_category_id'],
        'OC_ITEM_DURATION' => $data['oc_item_duration'],
        'ITEM_DELIVERY_TIME' => $data['item_delivery_time'],
        'IS_POSTED' => (!empty($data['is_posted']) ? 1 : 0),
        'NOW' => $now
    );
    $conn->query($sql, $binds);

    $sql2 = "UPDATE $oc_item_synchro SET ";
    $sql2 .= "oc_other_config = :OC_OTHER_CONFIG ";
    $sql2 .= "WHERE oc_product_id = :OC_PRODUCT_ID";
    $binds2 = array(
        'OC_OTHER_CONFIG' => serialize($data['oc_other_config']),
        'OC_PRODUCT_ID' => $id
    );
    $conn->query($sql2, $binds2);
}

$objectManager = MagentoFrameworkAppObjectManager::getInstance();
$resource = $objectManager->get('MagentoFrameworkAppResourceConnection');
$connection = $resource->getConnection();
$sql = "select * from mymodule_shipping where mymodule_shipping_id=$_REQUEST[m_shipping_id]";
$sql = $connection->quote($sql);
$connection->query($sql);