Edit report at http://bugs.php.net/bug.php?id=54181&edit=1
ID: 54181
User updated by: carsten_sttgt at gmx dot de
Reported by: carsten_sttgt at gmx dot de
Summary: MySQLi doesn't always reuse persistent link inside
same script
Status: Bogus
Type: Bug
Package: MySQLi related
PHP Version: Irrelevant
Block user comment: N
Private report: N
New Comment:
> MySQL should behave the same but is probably affected
> by the new_link parameter
Ok, this one I can understand (I think...)
| $con1 = mysqli_connect('localhost', 'foo', '');
| $con2 = mysqli_connect('localhost', 'foo', '');
is resulting in 2 connections, so:
| $con1 = mysqli_connect('p:localhost', 'foo', '');
| $con2 = mysqli_connect('p:localhost', 'foo', '');
is also resulting in 2 connections.
| $con1 = mysql_connect('localhost', 'foo', '');
| $con2 = mysql_connect('localhost', 'foo', '');
is resulting in 1 connections, so:
| $con1 = mysql_pconnect('localhost', 'foo', '');
| $con2 = mysql_pconnect('localhost', 'foo', '');
is also resulting in 1 connections.
(no new_link)
But what's with PDO_MySQL?
| $con1 = new PDO('mysql:host=localhost', 'foo', '');
| $con2 = new PDO('mysql:host=localhost', 'foo', '');
is resulting in 2 connections, but:
| $con1 = new PDO('mysql:host=localhost', 'foo', '',
| array(PDO::ATTR_PERSISTENT => true));
| $con2 = new PDO('mysql:host=localhost', 'foo', '',
| array(PDO::ATTR_PERSISTENT => true));
is resulting in 1 connections.
Thus this "bug" should be assigned to PDO/PDO_MySQL? (Maybe as change
request).
Or as "Doc" for MySQLi/PDO how this is working in detail.
BTW:
I think there should be consequent behavior how thinks are working. Or a
better description how a extension is working. For mysql_pconnect there
is an exact description:
| First, when connecting, the function would first try to find a
(persistent)
| link that's already open with the same host, username and password. If
one
| is found, an identifier for it will be returned instead of opening a
new
| connection.
Previous Comments:
------------------------------------------------------------------------
[2011-03-08 09:34:39] scott...@php.net
The problem with using the same connection twice is that with unbuffered
results
you can't run more than query at once. MySQLi only puts a connection up
for availability until after its done with it.
MySQL should behave the same but is probably affected by the new_link
parameter
which returned the same connection if all the parameters matched. It
wasn't
persistance just an optimization that caused more confusion than
anything else.
------------------------------------------------------------------------
[2011-03-07 19:53:34] carsten_sttgt at gmx dot de
> This is working as expected, persistent connections are only
> re-used if they're no longer in use by another script.
OK, with "another Script" you also mean the same script. Just to
recapitulate:
| <?php
| $con1 = mysqli_connect('p:localhost', 'foo', '');
| $con2 = mysqli_connect('p:localhost', 'foo', '');
| ?>
$con1 is already in use, so $con2 will results in a second connection.
If this is the expected behavior, why is this script:
| <?php
| $con1 = new PDO(
| 'mysql:host=localhost',
| 'foo', '',
| array(PDO::ATTR_PERSISTENT => true)
| );
| $con2 = new PDO(
| 'mysql:host=localhost',
| 'foo', '',
| array(PDO::ATTR_PERSISTENT => true)
| );
| ?>
or
| <?php
| $con1 = mysql_pconnect('localhost', 'foo', '');
| $con2 = mysql_pconnect('localhost', 'foo', '');
| ?>
resulting in 1 connection? $con1 is already in use, but $con2 is using
the same connection as $1.
------------------------------------------------------------------------
[2011-03-07 17:28:31] scott...@php.net
This doesn't have anything to do with persistent connections, with
mysql_connect()
if you open a connection with the same parameters it won't return a new
link
unless you set the 4th parameter to true.
This is working as expected, persistent connections are only re-used if
they're no
longer in use by another script.
------------------------------------------------------------------------
[2011-03-07 15:10:49] carsten_sttgt at gmx dot de
Description:
------------
If I open an existing persistent link a second (or 3rd, ...) time inside
the same script, MySQLi is only reusing the existent link if I have
explicitly closed the link before. At the moment it's always creating a
new link.
With MySQL it's working as expected.
Test script:
---------------
<?php
$con1 = mysqli_connect('p:localhost', 'foo', '');
var_dump($con1->thread_id);
$con2 = mysqli_connect('p:localhost', 'foo', '');
var_dump($con2->thread_id);
mysqli_close($con1);
mysqli_close($con2);
echo "---\n";
$con3 = mysqli_connect('p:localhost', 'bar', '');
var_dump($con3->thread_id);
mysqli_close($con3);
$con4 = mysqli_connect('p:localhost', 'bar', '');
var_dump($con4->thread_id);
mysqli_close($con4);
echo "===\n";
$con5 = mysql_pconnect('localhost', 'foo', '');
var_dump(mysql_thread_id($con5));
$con6 = mysql_pconnect('localhost', 'foo', '');
var_dump(mysql_thread_id($con6));
mysql_close($con5);
mysql_close($con6);
echo "---\n";
$con7 = mysql_pconnect('localhost', 'bar', '');
var_dump(mysql_thread_id($con7));
mysql_close($con7);
$con8 = mysql_pconnect('localhost', 'bar', '');
var_dump(mysql_thread_id($con8));
mysql_close($con8);
?>
Expected result:
----------------
int(1)
int(1)
---
int(2)
int(2)
===
int(3)
int(3)
---
int(4)
int(4)
Actual result:
--------------
int(1)
int(2)
---
int(3)
int(3)
===
int(4)
int(4)
---
int(5)
int(5)
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/bug.php?id=54181&edit=1
