Receiving Error Message, despite data being sent - php

Question

I have recently implemented a number of if statements that check to see if the require data has been entered, if not then I receive the error message something is wrong with.... But after implementing them I now recieve that error message regardless of whether the data is in fact being sent to the database (the data that is being sent is all correct) and I can't for the life of me figure out why.
$query = "insert into $sql_table (Eoi, Job_reference_number, First_Name, Last_Name, Street_Address, Suburb, State, Postcode, Email, Phone_Number, Skills) values ('$eoi','$jobNumber', '$firstName', '$lastName', '$streetAddress', '$suburb', '$state', '$postcode', '$emailAddress', '$phoneNumber', '$skills')";
$result = mysqli_query($conn, $query);
if($jobNumber = ''){
$result = false;
}
if($firstName = ''){
$result = false;
echo "<p> Something is wrong with your First Name </p>";
}
if($lastName = ''){
$result = false;
echo "<p> Something is wrong with your Last Name </p>";
}
if($streetAddress = ''){
$result = false;
echo "<p> Something is wrong with your Street Address </p>";
}
if($suburb = ''){
$result = false;
echo "<p> Something is wrong with your Suburb </p>";
}
if($postcode = ''){
$result = false;
echo "<p> Something is wrong with your Postcode </p>";
}
if($email = ''){
$result = false;
echo "<p> Something is wrong with your Email </p>";
}
if($phoneNumber = ''){
$result = false;
echo "<p> Something is wrong with your Phone Number </p>";
}
if($skills = ''){
$result = false;
echo "<p> Something is wrong with your Skills </p>";
}
if($result != mysqli_query($conn, $query)) {
echo "<p>Something is wrong with ", $query, "</p>";
}else {
echo "<p class=\"ok\">Successfully added a New EOI record</p>";
}
}
}
mysqli_close($conn);
I expect the result to be Successfully added a new EOI record when the user inputs valid data but instead I get the error message.

Answer 1

First you have a syntax error in if statement
if statement should be == not =
if($yourVariable == ''){
echo "<p> Something is wrong with your yourVariable </p>";//no meaning of this line
$result = false;
}
it means if your variable is empty then $result will false and you're can check it in your last if
Second you are checking all variable after DB insertion, you need to do it before insertion in db