Multiple if else in mysql query - php

Question

I have re-written this question because of all the down votes and it would seem that either no one understood the question or was unwilling to help a newbie. So I'll as it this way: Can someone tell/show me why this code does not work? (500 error)
OR... at the very least point me in the right direction? I AM WILLING TO LEARN, I just don't know where to begin or who/where to learn from as I am not sure what to even ask other than how do you run multiple "else" statements... that however left me more confused than I already am though!
Any "HELP" would be greatly appreciated!
<?php
$servername = "localhost";
$username = "****";
$password = "***";
$dbname = "***";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
$bname = $_POST['bname'];
$baddress = $_POST['baddress'];
$bcity = $_POST['bcity'];
$bstate = $_POST['bstate'];
$zipcode = $_POST['zipcode'];
// Check connection
if ($conn->connect_error)
{
die("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT Login FROM `USERS` WHERE Business_Name = '" . $_POST["bname"] . "' AND Business_Address = '" . $_POST["baddress"] . "' AND Business_State = '" . $_POST["bstate"] . "' AND Business_Zip = '" . $_POST["zipcode"] . "' LIMIT 1";
$result = $conn->query($sql);
if ($result->num_rows > 0)
{
// output data of each row
while ($row = $result->fetch_assoc())
{
echo "https://www.***.com/realsite.php?Login=" . $row["Login"] . "";
}
}
else
{
$sql = "SELECT Login FROM `DATA` WHERE Business_Name = '" . $_POST["bname"] . "' AND Business_Address = '" . $_POST["baddress"] . "' AND Business_State = '" . $_POST["bstate"] . "' AND Business_Zip = '" . $_POST["zipcode"] . "' LIMIT 1";
$result = $conn->query($sql);
if ($result->num_rows > 0)
{
// output data of each row
while ($row = $result->fetch_assoc())
{
echo "https://www.***.com/demo.php?Login=" . $row["Login"] . "";
}
}
else
{
$sql = "INSERT INTO `DATA` (Business_Name, Business_Address, Business_City, Business_State, Business_Zip)
SELECT '$bname', '$baddress', '$bcity', '$bstate', '$zipcode' FROM (SELECT 1) t
WHERE NOT EXISTS (SELECT Login, Business_Name,Business_Address FROM `DATA` WHERE Business_Name='$bname' AND Business_Address='$baddress')";
if (mysqli_query($conn, $sql))
{
echo "<a href='https://www.servedwell.com/realsite.php?Login=" . $row["Login"] . "'>LINK</a>";
}
else
{
echo "Error: " . $sql . "<br>" . mysqli_error($conn);
}
}
mysqli_close($conn);
}
?>

Answer 1

Credit goes to #Ancaron for properly formatting code and correcting a syntax error. Final posted code works fine.