I try to get more than 3 feed from other web site and show it in my site like :

    function fw_shortcode( $atts ) {
    
    	global $wpdb, $feedtable;
    	$result=mysql_query("SELECT * FROM " . $feedtable . " ORDER BY RAND() LIMIT 3");
    
    	while( $row=mysql_fetch_array($result) ) {	
    		$rss = fetch_feed($row["weburl"]);
    		if (!is_wp_error( $rss ) ) : 
    
    			$maxitems = $rss->get_item_quantity(1);
    			$rss_items = $rss->get_items(0, $maxitems);
    
    			foreach ( $rss_items as $item ) :
    					
    				$code .= '	<article class="col-md-4 col-sm-6 col-xs-12" itemscope="" itemtype="http://schema.org/BlogPosting">
    								<div class="vendoritem">';
    				$code .= '			<a href="' . esc_url( $item->get_permalink() ) . '"  target=' . "_blank".'>';
    				$code .= '				<img width="300" height="225" src="' . get_first_image_url($item->get_description()) . '" class="img-responsive relat wp-post-image" style="background-color:#3498db;">';
    				$code .= '			</a>
    									<div class="vendoritem__details">
    										<a href="' . esc_url( $item->get_permalink() ) . '" class="vendoritem__title" target=' . "_blank" . '>' . esc_html( $item->get_title() ) . '</a>
    									</div>
    								</div>
    							</article>';
    
    			endforeach;
    
    		endif;
    		/* End Loop */
    	}
    
    	$code .= '</div>';
    
    	return $code;
    
    	wp_reset_query();
    
    }

My problem is i need to shoe only random 3 feed from table. but **some time** show me 2 feed, Why !!, and if any feed not work, how can get other feed from DB