Query 2 Databases at Once

[transfield]

Hello,
I have 2 MySQL databases which I'd like to query together at the same time. Both databases have got different names, usernames & passwords. In this case, how do I:-

1. Write the mysql_connect and mysql_select_db statement to establish connection with both databases at the same time?

2. Write the correct SELECT statement to query both databases at the same time?

Thank you for your advice.

[bradgrafelman]

I'm not sure if this is possible... at least using only one connection.

What you can do is have two connections to the MySQL server connecting with two different usernames and selecting two different databases.

Depending on the application here, you would just pull the data from each connection that you need, and use PHP to put them together.

[nickadeemus2002]

this is interesting. is it possible to store two database resources as elements in an array and use that as a connection paramteter? i'll see if i have time to test something like that.

[bradgrafelman]

Well, you can do that or you can have two separate variables. Either way, I suppose. Just make sure you're passing the correct resource to the correct query.

$connection = array();

$connection['database1'] = mysql_connect('localhost', 'user1', 'pass1', TRUE);
$connection['database2'] = mysql_connect('localhost', 'user2', 'pass2', TRUE);

if(!mysql_select_db('database1', $connection['database1']))
     die('MySQL error: ' . mysql_error($connection['database1']));
if(!mysql_select_db('database2', $connection['database2']))
     die('MySQL error: ' . mysql_error($connection['database2']));

// etc.