persistence of mysql_pconnect()

[nairit]

I have a question on mysql_pconnect().Please if anyone can help mail me at [e-mail] or reply in phpbuilder.com

It is well documented in manuals that a resource opened by
$link = mysql_pconnect("host", "user", "pass");
cannot be closed by mysql_close();

Suppose the resource $link is declared as a private member of a class.
private $link;

Then
$this->link = mysql_pconnect("host", "user", "pass");
this is executed from some public function connector() of the class by invoking the function as say
$ob_class1->connector();
After that we are executing SQL statements using the connection established by that resource.

Now my question is if the class object is killed by
unset($ob_class1);
will the persistent connection remain alive? Or is the connection being re-established from scratch as in mysql_connect() when the function connector() is again executed from some other page
?? :-)

[Roger_Ramjet]

A persistent connection will persist untill you restart the mysql server. There are absoultely NO advantages from using persistent connections except when the mysql server is on a seperate box AND accessed over a slow network link. Since that is rarely the situation then there is rarely any use in using persistent connections, BUT THERE ARE DOWNSIDES.

Warning

There are a couple of additional caveats to keep in mind when using persistent connections. One is that when using table locking on a persistent connection, if the script for whatever reason cannot release the lock, then subsequent scripts using the same connection will block indefinitely and may require that you either restart the httpd server or the database server. Another is that when using transactions, a transaction block will also carry over to the next script which uses that connection if script execution ends before the transaction block does. In either case, you can use register_shutdown_function() to register a simple cleanup function to unlock your tables or roll back your transactions. Better yet, avoid the problem entirely by not using persistent connections in scripts which use table locks or transactions (you can still use them elsewhere).

You can also run out of available connections very easily with pconnect.

Drop them and just use normal mysql_connect().