2009/11/11 Chris <dmagick@xxxxxxxxx>: > Andy Shellam (Mailing Lists) wrote: >> >> Hi, >> >>> >>> If the databases are in the same mysql server, then you could qualify >>> the table select with the database name and simply re-use the >>> connection >>> >>> select db_name.table_name.field from db_name.table_name [where] >> >> No offence, but if I saw this in an application's source code, I'd run a >> mile. > > Plus the assumption that they are on the same server and that the user > you're connecting with has access to both databases.. > > -- > Postgresql & php tutorials > http://www.designmagick.com/ > > > -- > PHP Database Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > > If it comes to that, if you are writing SQL code in PHP rather than abstracting it or using stored procedures/views/etc. ... Essentially the issue is 2 identical connections are not actually 2 identical connections. They are 2 references to a single connection. So, changing the DB via 1 resource changes the db for both resources. NOTE: IDENTICAL. If the server or username is different, then that results in a separate connection. <?php $conn1 = mysql_connect($server, $username, $password); $conn2 = mysql_connect($server, $username, $password); // Is the same connection as $conn1 mysql_select_db($db1, $conn1); // Both connection resources are now looking at db1. mysql_select_db($db2, $conn2); // Both connection resources are now looing at db2. _ONE_ solution is to use fully qualified names (you can use constants if you don't like hard-coding the db name in the query). Another option is to set the new_link flag on the mysql_connect() call. That way you will have 2 separate connections. <?php $conn1 = mysql_connect($server, $username, $password, true); $conn2 = mysql_connect($server, $username, $password, true); // Is NOT the same connection as $conn1 mysql_select_db($db1, $conn1); // Points to db1 for connection1 mysql_select_db($db2, $conn2); // Points to db2 for connection2 -- ----- Richard Quadling "Standing on the shoulders of some very clever giants!" EE : http://www.experts-exchange.com/M_248814.html Zend Certified Engineer : http://zend.com/zce.php?c=ZEND002498&r=213474731 ZOPA : http://uk.zopa.com/member/RQuadling -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
