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Why do I get the error Warning: mysqli_query() expects at least 2 parameters, 1 given?
Below is the line that's not working:
mysqli_query("UPDATE `tbl_users` SET `profile` = '" . ($file_path) . "' WHERE `userID` = " . (int)$user_id);
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Please search on Google. First hit: http://php.net/manual/en/mysqli.query.php
First parameter should be the connection resource. So the output from mysqli_connect.
When you create the connection to the mysql server like this:
$conn = mysqli_connect($servername, $username, $password);
You stored the connection in $conn
mysqli_query("connection variable","SQL Query");
In your case.. is missing the connection variable.
Try something like this (asuming that the variable you used to store the connection is named $conn):
mysqli_query($conn, "UPDATE `tbl_users` SET `profile` = '" . ($file_path) . "' WHERE `userID` = " . (int)$user_id);