<?php
$isOk=array();
#this function is to check does all variables is set and does all has a value 
function checkData ()
{
   
   if (isset($_POST['LineID'])){
      if(!empty($_POST['LineID'])){
         $isOk[]="TRUE";
      }
      else {
            $isOk[]="FALSE";
            
         }
      }
      if (isset($_POST['Time'])){
      if(!empty($_POST['Time'])){
         $isOk[]="TRUE";
      }
         else {
            $isOk[]="FALSE";
            
         }
      }
            if (isset($_POST['Date'])){
      if(!empty($_POST['Date'])){
         $isOk[]="TRUE";
      }
         else {
            $isOk[]="FALSE";
            
         }
      }
      if (isset($_POST['pagevisited'])){
      if(!empty($_POST['pagevisited'])){
         $isOk[]="TRUE";
      }
         else {
            $isOk[]= "FALSE";
            
         }
      }
            if (isset($_POST['application'])){
      if(!empty($_POST['application'])){
         $isOk[]="TRUE";
      }
         else {
            $isOk[]="FALSE";
            
         }
      }
   if (isset($_POST['user'])){
      if(!empty($_POST['user'])){
         $isOk[]="TRUE";
      }
         else {
            $isOk[]="FALSE";
            
         }
      }
         if (isset($_POST['Client_ID'])){
      if(!empty($_POST['Client_ID'])){
         $isOk[]="TRUE";
      }
         else {
            $isOk[]="FALSE";
            
         }
      }
      #if some elemnt of an array have string with value FALSE then return false
      if (in_array("FALSE", $isOk)) {
         return FALSE;
      } else {
         return TRUE;
      }
      
 }
 #if all ariables are OK then connect to the DB and process data
 if (checkData()){
     $dbc = mysqli_connect('localhost','','','');
     #code…
 }
 else{
   echo "Fail!";
 }