mysql queries for insert, update, check record existence with sql prevention

mysql_queries

<?php

//INSERT

		function store_feedback($message,$name,$email)
		{
			$con = mysqli_connect('127.0.0.1', 'root', '', 'mysql');				
			if (mysqli_connect_errno())
			{
				echo "Failed to connect to MySQL: " . mysqli_connect_error();
				return;
			}
			$insertQuery1 = "INSERT INTO feedback(`name`,`email`,`message`) VALUES ('".$name."','".$email."','".$message."')";
			if (!mysqli_query($con,$insertQuery1))
		  		{
		  		//	die('Error: ' . mysqli_error($con));
					echo "error";
				}		
			return;
		}

//SELECT

	function get_category_url($category)
		{
			$con = mysqli_connect('127.0.0.1', 'root', '', 'mysql');
			if (mysqli_connect_errno())
			{
				echo "Failed to connect to MySQL: " . mysqli_connect_error();
				return;
			}	
			$today = date("Ymd");	
			$result = mysqli_query($con,"SELECT url,img_url,sentiment,title,category from frrole_cateogry_article where category='".$category."' AND today <= '".$today."' AND title != '' AND img_url != '' order by today desc, rt_count DESC limit 3 ");
			while ($row = @mysqli_fetch_array($result))
			{
				$url = $row['url'];
  			$img_url = $row['img_url'];
				$title = $row['title'];				
				$pcount = $row['sentiment'];
			}
		}
		
//CHeCK RECORD EXISTENCE
	
		function getPnr()
  	{
  		$con = mysqli_connect('127.0.0.1', 'root', '', 'safari');
  		if (mysqli_connect_errno())
  		{
  		    echo "Failed to connect to MySQL: " . mysqli_connect_error();
  		    return;
  		}
  		$pnr = mt_rand(1111111111, 99999999999);				
  		$result = mysqli_query($con,"SELECT user_pnr from tbl_user where user_pnr = '".$pnr."'");
  		if(mysqli_num_rows($result)>0)
  			getPnr();
  		else
  		return $pnr;
	}
		
//SQL INJECTION PREVENT. Enclose var from user with real escape string
	{
	  $from = mysql_real_escape_string($_GET['from']);
		$to = mysql_real_escape_string($_GET['to']);
		$seats = mysql_real_escape_string($_GET['seats']);
		$date = mysql_real_escape_string($_GET['date']);
	}	
	
//Get single variable and compare it

	function isConfirm($user_id)
	{
			$con = mysqli_connect('127.0.0.1', 'root', '', 'safari');				
			if (mysqli_connect_errno())
			{
				echo "Failed to connect to MySQL: " . mysqli_connect_error();
				return;
			}
			$result = mysqli_query($con,"select user_pnr from tbl_user where user_id = '".$user_id."' AND isConfirm = 'No' ");
			$row = @mysqli_fetch_row($result);
			echo $row[0];
			return;
	}

?>