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====== Creating A Connection Pool ======
Each of the connections in the connection pool are defined in the exact same way as a normal ADOdb connection, which makes it simple to add the functionality of existing code. This is shown below:

^ Existing ADOdb Connection                                   ^ Load Balance                                                                                  ^
|                                                             | Instantiate Load Balancer as $db                                                              |
| Instantiate ADOdb as $db                                    | Instantiate ADOdb as $db0, designating the connection as the primary (read-write) connection  |
| Connect $db to database using normal connection parameters  | Connect $db0 to database using normal connection parameters                                   |
|                                                             | Add connection $db0 to connection pool $db                                                    |
|                                                             | Instantiate ADOdb as $db1, designating the connection as a secondary (read-only) connection   |
|                                                             | Add Connection $db1 to connection pool $db                                                    |
|                                                             | Repeat for available number of secondary servers                                              |
| Execute commands against connection $db                     | Execute commands against connection pool $db                                                  |

We show that here, first by creating a normal connection, using a MySQL database
<code php>
$db = newAdoConnection('mysqli');
$db->connect('host','user','pass','database');
$db->execute('select * from employees');
</code>
If we create a load balanced connection, but only assign one server, the method is exactly the same
<code php>
$db = new ADOdbLoadBalancer;

$db0 = new ADOdbLoadBalancerConnection('write',1,'host','user','pass','database');
$db->addConnection($db0);

$db->execute('select * from employees')
</code>

Note that because we have not assigned any ''readonly'' nodes, the ''write'' node assumes the responsibility