2009/12/17 Richard Quadling <rquadling@xxxxxxxxxxxxxx>: > 2009/12/17 唐家兴 <tjxing.1988@xxxxxxxxx>: >> I want to ask a strange question. >> >> As we know, if we connect a mysql database in the same host twice with the >> same username, we won't get two new link, but two handle to only one link. >> Then, if I close one of them, whether the other one will be closed together? >> >> I wrote two pieces of code. The first is like this >> <?php >> $db1 = mysql_connect($host, $username, $pwd); >> $db2 = mysql_connect($host, $username, $pwd); >> $sql = 'show databases'; >> mysql_close($db1); >> $res = mysql_query($sql, $db2); >> $a = mysql_fetch_row($res); >> print_r($a); >> ?> >> Then the output of the $db2 is correct. So the $db2 isn't closed together >> with the $db1. >> >> But when I add a line among the code, the result is different >> <?php >> $db1 = mysql_connect($host, $username, $pwd); >> $db2 = mysql_connect($host, $username, $pwd); >> $sql = 'show databases'; >> mysql_close($db1); >> $db1 = true; //a new line >> $res = mysql_query($sql, $db2); >> $a = mysql_fetch_row($res); >> print_r($a); >> ?> >> Then the output is wrong. The PHP tell me that the link is not a valid one. >> I don't know how an assignment operation for the $db1 can close the $db2. >> Could someone help me. >> I'll appreciate your help. >> > > When you xxx_connect() with the same parameters, internally, you are > sharing the connection. It seems that killing one of the references > kills all the references. > > The solution is to a use the fourth parameter on mysql_connect(). The > "new_link" param. > > So ... > > <?php > $db1 = mysql_connect($host, $username, $pwd, True); // Make sure a new > link is created. > $db2 = mysql_connect($host, $username, $pwd, True); // Make sure a new > link is created. > $sql = 'show databases'; > mysql_close($db1); > $db1 = true; //a new line > $res = mysql_query($sql, $db2); > $a = mysql_fetch_row($res); > print_r($a); > ?> > > should work. > http://docs.php.net/mysql_connect -- ----- 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 General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
