We have MySQL table called “students” holding 90 records with the following fields:
Name – varchar(250)
PhoneNumber – varchar(250)
Instead of doing a single SELECT query and display all the 90 records on a single page we can have 5 pages each containing maximum 20 records. To do this we will need to use the LIMIT clause for SELECT command so we can limit the query to show only 20 records. The LIMIT clause also allows you to specify which record to start from. For example this query
$sql = "SELECT * FROM students ORDER BY name ASC LIMIT 0, 20";
returns 20 records sorted by name starting from the first record. This next query
$sql = "SELECT * FROM students ORDER BY name ASC LIMIT 50, 20";
shows 20 records sorted again by name but this time it will start from the 50th record.
So basically in this clause (LIMIT start, count) ‘start’ specify the starting record and ‘count’ specifies how many records to show.
Next thing to do is to make a PHP file called pagination.php which will show the first 20 records from our table. The code below selects and then prints the data in a table.
<?php if (isset($_GET["page"])) { $page = $_GET["page"]; } else { $page=1; }; $start_from = ($page-1) * 20; $sql = "SELECT * FROM students ORDER BY name ASC LIMIT $start_from, 20"; $rs_result = mysql_query ($sql, $connection); ?> <table> <tr><td>Name</td><td>Phone</td></tr> <?php while ($row = mysql_fetch_assoc($rs_result)) { ?> <tr> <td><? echo $row["Name"]; ?></td> <td><? echo $row["PhoneNumber"]; ?></td> </tr> <?php }; ?> </table>
Now, when you open pagination.php in your web browser you will see table showing the first 20 records from your ‘students’ table.
The first 2 lines of the above code
if (isset($_GET["page"])) { $page = $_GET["page"]; } else { $page=1; }; $start_from = ($page-1) * 20;
are used to create a $start_from variable depending on the page that we want to view. Later you will see that we will pass a “page” value using the URL (e.g. pagination.php?page=2) to go to different pages. Next we need to find out the total amount of records in our table and the number of pages that we will need. To do this we run another query using COUNT() function.
$sql = "SELECT COUNT(Name) FROM students"; $rs_result = mysql_query($sql,$connection); $row = mysql_fetch_row($rs_result); $total_records = $row[0];
The $total_records is now equal to the number of records that we have in our database, in our case 90. We have 20 records per page so the total number of pages that will be needed is 5 (4 pages with 20 records and last page will have 10 records).
Calculating the amount of pages needed using PHP can be done using ceil() function.
$total_pages = ceil($total_records / 20);
We divide the total number of records by records per page and then the ceil() function will round up the result. Now we have 2 new variables - $total_records equal to 90 and $total_pages equal to 5.
To print page numbers and associate URLs to each number we will use for() cycle.
<?php for ($i=1; $i<=$total_pages; $i++) { echo "<a href='pagination.php?page=".$i."'>".$i."</a> "; }; ?>
Above code will print numbers from 1 to 5 and for each number will create different link.
pagination.php?page=1
pagination.php?page=2
pagination.php?page=3
pagination.php?page=4
pagination.php?page=5
as you can see each link passes different page value which is used in the SELECT query above.
At the end you should have a file like this (remember to add the MySQL connection string):
<?php if (isset($_GET["page"])) { $page = $_GET["page"]; } else { $page=1; }; $start_from = ($page-1) * 20; $sql = "SELECT * FROM students ORDER BY name ASC LIMIT $start_from, 20"; $rs_result = mysql_query ($sql,$connection); ?> <table> <tr><td>Name</td><td>Phone</td></tr> <?php while ($row = mysql_fetch_assoc($rs_result)) { ?> <tr> <td><? echo $row["Name"]; ?></td> <td><? echo $row["PhoneNumber"]; ?></td> </tr> <?php }; ?> </table> <?php $sql = "SELECT COUNT(Name) FROM students"; $rs_result = mysql_query($sql,$connection); $row = mysql_fetch_row($rs_result); $total_records = $row[0]; $total_pages = ceil($total_records / 20); for ($i=1; $i<=$total_pages; $i++) { echo "<a href='pagination.php?page=".$i."'>".$i."</a> "; }; ?>
This pagination.php file will print a table with maximum 20 records per page and at the bottom 5 page numbers each pointing to a page showing different 20 records.
Do not forget that for a small fee I can add pagination to all your PHP files. Let me know if you need help with this and I will give you a quote.
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