Creating next button to loop through mysql table - php

Question

I'm trying to make the below code have an if/else statement in the while section? I'm trying to do something like, if the result is the last row in the mysql table then display the first row in the table. Otherwise display the id row from the $id_related variable.
My goal is to create a 'next' button that esentially loops through the database table - going from id 1 to 10 and when the user gets to 10 and pushes 'next' button, it goes back to id 1.
require('connect.php');
$id_related = mysqli_real_escape_string($db, $_GET['id']);
$sql_related = <<<SQL
SELECT *
FROM `article_img`
WHERE `id` > '$id_related' ORDER BY id LIMIT 1
SQL;
if(!$result = $db->query($sql_related)){
die('There was an error running the query [' . $db->error . ']');
}
while($row = $result->fetch_assoc()){
echo '
<a href="article.php?id='.$row['id'].'&size='.$row['size'].'">
<div style="background-image: url('.$row['img'].');">
</div>
</a>
';
}

Answer 1

Note:
You can check the number of rows your query will return. If the current $_GET['id'], for example is 10 then binds on your query, and it returns 0, go back to the first id row of your table. So you don't have to worry updating your code in the future if you want to extend the rows of your table.
You should use mysqli_* rather than the deprecated mysql_* API.
Your code for connect.php:
$con = new mysqli("YourHost", "Username", "Password", "Database"); /* REPLACE NECESSARY DATA */
/* CHECK CONNECTION */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
And your main code:
require('connect.php'); /* YOUR CONNECTION */
if($stmt = $con->prepare("SELECT id,size,img FROM article_img WHERE id > ? ORDER BY id LIMIT 1")){
$stmt->bind_param("i",$_GET["id"]); /* BIND THIS VARIABLE TO YOUR QUERY */
$stmt->execute(); /* EXECUTE QUERY */
$stmt->store_result(); /* NECESSARY WHEN GETTING THE NUMBER OF ROWS */
$noofrows = $stmt->num_rows; /* GET NUMBER OF ROWS */
if($noofrows == 0){ /* IF FOUND NO ROW GREATER THAN CURRENT CODE */
/* GET THE FIRST ROW IN YOUR article_img */
$stmt2 = $con->prepare("SELECT id,size,img FROM article_img ORDER BY id LIMIT 1")){
$stmt2->execute();
$stmt2->store_result();
$stmt2->bind_result($id,$size,$img);
$stmt2->fetch();
$stmt2->close();
} /* END OF SECOND PREPARED STATEMENT */
} /* END OF IF $noofrows IS 0 */
else { /* IF THERE IS A VALID NEXT ROW */
/* GET THE NEXT PAGE */
$stmt->bind_result($id,$size,$img); /* BIND THE RESULT TO THESE VARIABLES OF THE FIRST QUERY */
$stmt->fetch(); /* FETCH THE RESULT */
} /* END OF ELSE */
$stmt->close();
} /* END OF PREPARED STATEMENT */
echo '<a href="article.php?id='.$id.'&size='.$size.'">
<div style="background-image: url('.$img.');">
</div>
</a>'; /* YOUR LINK TO NEXT PAGE */