search partner insert posts

<?php
$con = mysqli_connect("localhost","root"," ","social_media") or die ("Connection was not established");
?>

//function for inserting posts
function insertPost(){


if (isset($_POST['sub'])){

global $con;
global $user_id;
$title = addslashes($_POST['title']);
$content = addslashes($_POST['content']);
$topic= addslashes$_POST['topic'];

if ($content==' ' OR $title==' ' ){

echo "<h2>Please enter topic description </h2>";
exit();
}
else {
$insert = "insert into posts(user_id,topic_id,post_title,post_content,post_date) value ('$user_id','$topic', '$title', '$content', NOW())";

$run = mysqli_query($con,$insert);

if($run){
$update = "update users set posts = 'yes' where user_id='$user_id'"
$run_update = mysqli_query($con,$update);
}



}

}




}
//function for displaying posts
function get_posts(){

global $con;

$per_page=5;
if (isset($_GET['page'])){
$page = $_GET['page'];

}

}