php mysqli not working - php

Question

I am making a chat application and this is the part that checks for new additions.
<?php
$servername = "*";
$username = "*";
$password = "****";
$dbname = "*";
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (mysqli_connect_error($conn)) {
die("Connection failed: " . mysqli_connect_error($conn));
}
$id = $_GET['id'];
$sql = "SELECT position, user, comment,time FROM chat WHERE position > $id";
$result = mysqli_query($conn,$sql);
if (mysqli_num_rows() > 0) {
// output data of each row
while($row = mysqli_fetch_assoc($result)) {
$row2 = mysqli_fetch_assoc(mysqli_query($conn,"SELECT * FROM login WHERE username=".$row['user']));
$userImage = $row2["avatar"];
echo "<div class='container-fluid well'><p class='left'>"."<img class='img-circle zoom' src='/profile_images/".
$userImage
."' style='width:32px;height:32px;'>".$row["user"]. ": " . $row["comment"]. "</p><h4><small class='right'> at ".$row['time']."</small></h4></div>";
}
}
mysqli_close($conn);
?>
it was working until I changed the line
$row2 = mysqli_fetch_assoc(mysqli_query($conn,"SELECT * FROM login WHERE username=".$row['user']));
Help would be appreciated.
Update:
this is my html:
There is more. but this is the most important
<div id='newchat'></div>
<script>
$(document).ready(function(){
getChat();
var id = <?php echo $id ?>;
function getChat(){
setTimeout(getChat,1000);
$.get("getChat.php?id="+id,function( text ) {
if (text != ""){
id ++;
$( "#newchat" ).prepend( text );
}
});
}
});
</script>

Answer 1

Try this query :
$row2 = mysqli_fetch_assoc(mysqli_query($conn,"SELECT * FROM login WHERE username='{$row['user']}'"));
Side note : Your query is unsafe. Read this
How can I prevent SQL injection in PHP?.

Answer 2

you forget 2 '
$row2 = mysqli_fetch_assoc(mysqli_query($conn,"SELECT * FROM login WHERE
username='".$row['user']."'"));

Answer 3

Simply use this query:
"SELECT * FROM login WHERE username='".$row['user']."'"
instead of
"SELECT * FROM login WHERE username=".$row['user']
and if you want a simple query then use:
$usr = $row['user'];
$row2 = mysqli_fetch_assoc(mysqli_query($conn,"SELECT * FROM
login WHERE username=$usr"));
It'll definitely work.

Answer 4

Write your query as below:-
$sql = "SELECT * FROM login WHERE username='{$row['user']}'";
mysqli_fetch_assoc(mysqli_query($conn,$sql));
Hope it will help you :)