PHP | MySql: mysql query concat in where clause - php

Question

How can I concatenate two columns in where clause
this is my normal query:
$result = mysql_query("SELECT stud_id FROM tb_student WHERE instructor_id = '$instructor_id' AND description = '$description' AND stud_fname = '$stud_fname' AND stud_lname = '$stud_lname'") or die(mysql_error());
I want the stud_fname and stud_lname to be concatenated.
here is my full code:
<?php
error_reporting(0);
$link = mysql_pconnect("localhost", "root", "") or die("Could not connect");
mysql_select_db("dbmobile_class_record") or die("Could not select database");
// array for JSON response
$response = array();
$instructor_id=$_GET['instructor_id'];
$description=$_GET['description'];
$stud_fname=$_GET['stud_fname'];
$stud_lname=$_GET['stud_lname'];
// get all items from myorder table
$result = mysql_query("SELECT stud_id FROM tb_student WHERE instructor_id = '$instructor_id' AND description = '$description' AND stud_fname = '$stud_fname' AND stud_lname = '$stud_lname'") or die(mysql_error());
if (mysql_num_rows($result) > 0) {
$response["student"] = array();
while ($row = mysql_fetch_array($result)) {
// temp user array
$student = array();
$student["stud_id"] = $row["stud_id"];
// push ordered items into response array
array_push($response["student"], $student);
}
// success
$response["success"] = 1;
}
else {
// order is empty
$response["success"] = 0;
$response["message"] = "No Records Found";
}
// echoing JSON response
echo json_encode($response);
?>

Answer 1

$instructor_id = $_GET['instructor_id'];
$description = $_GET['description'];
$fullname = $_GET['fullname'];
// get all items from myorder table
$result = mysql_query("SELECT stud_id FROM tb_student WHERE instructor_id = '$instructor_id' AND description = '$description' AND CONCAT(stud_fname, ' ', stud_lname) = '$fullname'") or die(mysql_error());

Answer 2

Use this one
$result = mysql_query("SELECT stud_id, CONCAT_WS('', stud_fname, stud_lname) AS stud_fullname FROM tb_student WHERE instructor_id = '$instructor_id' AND description = '$description' AND stud_fname = '$stud_fname' AND stud_lname = '$stud_lname'") or die(mysql_error());
stud_fullname should contain what you want.