php if username exist in database increase username by one - php

Question

I am a bit stuck with my code.
I am practising and would like to achive the following.
Before an user sign up, i want to check the users username exists, if exists than increase the name by one.
So my logic works like this. User gives his/her first and last name, generates an username based on that.
function
function unique_name($first_name, $last_name) {
$username = strtolower($first_name.'.'.$last_name)
$check = mysqL_query(" SELECT username WHERE username = '".$username."' ");
if(count($check == 1)) {
$i = 2;
foreach($check as $user) {
return $user['username'].$i;
$i++;
}
} else {
return $username;
}
}
$username = unique_name($_POST['first_name'], $_POST['last_name']);
// saveing the increased username
So actually the script should check if the generated unique username exsits if exsits increase, and encrease it even if it exsits with a number
example
Tom Anderson signs up, username will be tom.anderson, saved as tom anderson
Second Tom Anderson signs up, username will be tom.anderson, it already exists, save the new one as tom.anderson2.
The third user signs up he is tom anderson too, username tom.anderson* exsits twice, increase to tom.anderson3.
So i dont have a problem checking if the user exsits and saveing it, my problem is, how to increase every username if exist?
I am not asking anybody to write this for me i am nust looking for a hint
Thank you
EDIT
Thank you for the replies but this does not work
if(count($check) == 1) {
$i = 2;
foreach($check as $user) {
return $user['username'].count($check);
$i++;
}
} else {
return $username;
}
This only check the username with out a number, so if username tom.anderson exists it increases to tom.anderson1 but if tom.anderson1 exists too it wont increase to tom.anderson2

Answer 1

Can you have something that just appends the count of the rows returned, unless it's 0?
if(count($check) > 0) {
return $user['username'].count($check);
} else {
return $username;
}
change the SQL:
" SELECT username WHERE username LIKE '".$username."%' "

Answer 2

Try to give like this
if(count($check) == 1) {
$i = 2;
foreach($check as $user) {
return $user['username'].count($check);
$i++;
}
} else {
return $username;
}

Answer 3

You may add new field into user table, and called it base_username.
Them fetch count rows with given username, and increase every username on count found
Something like this
`function unique_name($first_name, $last_name) {
$unique_name = $username = strtolower($first_name.'.'.$last_name)
$cnt = get_row(" SELECT COUNT(*) from `users` WHERE base_username = '".$username."' LIMIT 1 ");
if($cnt){
$unique_name = $username . $cnt + 1;
}
return $unique_name;
}`