Membagi 2 Data di dalam Database Menggunakan Codeigniter

Assalam,.. seperti ini contoh koding lengkapnya, semoga bermanfaat :
<?php
$server = "localhost";
$username = "root";
$password = "";
$database = "db_kampus";
 
mysql_connect($server,$username,$password) or die ("Gagal");
mysql_select_db($database) or die ("Database tidak ditemukan");
 
$hitung = mysql_query("SELECT * FROM dosen");
$jumlah_kiri = number_format(mysql_num_rows($hitung)/2);
 
$no = 1;
echo "<table border='1'>";
$query = mysql_query("SELECT * FROM dosen ORDER BY id_dosen DESC LIMIT 0,$jumlah_kiri");
while($row = mysql_fetch_array($query)){
	echo "<tr><td>$no</td> <td>$row[nama_dosen]</td></tr>";
	$no++;
}
echo "</table>";
 
$noo = $jumlah_kiri+1;
echo "<table border='1'>";
$query = mysql_query("SELECT * FROM dosen ORDER BY id_dosen DESC LIMIT $jumlah_kiri,$jumlah_kiri");
while($row = mysql_fetch_array($query)){
	echo "<tr><td>$noo</td> <td>$row[nama_dosen]</td></tr>";
	$noo++;
}
echo "</table>";
?>